Design Guide for Residential PEX Water Supply Plumbing Systems

DESIGN GUIDE Residential PEX Water Supply Plumbing Systems Applications Advantages Material Properties Joining Methods Code Acceptance Design Installation and more PLASTICSPIPEINSTITUTE PPFA Plastic Pipe and Fittings Association NAHB RESEARCH CENTER PATH Partnership for Advancing Technology in Housing Image of a house with plumbing illustrations DESIGN GUIDE Residential PEX Water Supply Plumbing Systems Prepared for Plastics Pipe Institute Inc PPI 105 Decker Court Suite 825 Irving TX 75062 wwwplasticpipeorg and Plastic Pipe and Fittings Association PPFA 800 Roosevelt Road Bldg C Ste 312 Glen Ellyn IL 60137 wwwppfahomeorg and Partnership for Advancing Technology in Housing 451 7th Street SW Washington DC 20410 wwwpathnetorg Prepared by NAHB Research Center Inc 400 Prince Georges Boulevard Upper Marlboro MD 20774 wwwnahbrcorg November 2006 This document was developed as the result of a consensus process involving the Plastic Pipe Institute the Plastic and Plastic Pipe and Fitting Association and representatives from numerous piping and fitting manufacturers It was prepared by the NAHB Research Center with support and research from the Partnership for Advancing Technology in Housing PATH 50 Acknowledgements We would like to thank the following principal contributors to this Guide Plastic Pipe and Fittings Association Glen Ellyn Illinois Richard Church Mike Cudahy Plastics Pipe Institute Irving Texas Camille Rubeiz Rehau Inc Leesburg Virginia Lance MacNevin Uponor Apple Valley Minnesota Randy Knapp Vanguard Piping Systems McPherson Kansas Gary Morgan Viega Wichita Kansas Christina Smith WattsRadiant Springfield Missouri Chris Haldiman Zurn Plumbing Products Group Commerce Texas Gary Runyan Department of Housing and Urban Development HUD Washington DC Dana Bres NAHB Research Center Upper Marlboro Maryland Robert Fuller Michael Grothe Megan Inouye Shawn Martin Joseph Wiehagen Anne Holtz and Kim Warren for editorial review and Edith Crane and Pam Eggleston for layout and design We would also like to acknowledge the support of the Partnership for Advancing Technology in Housing PATH and the material support of the Delta Faucet Company Copyright Copyright 2006 NAHB Research Center Inc Plastics Pipe Institute Plastic Pipe and Fittings Association All rights reserved Disclaimer Neither the NAHB Research Center Inc the Plastics Pipe Institute the Plastic Pipe and Fitting Association the US Department of Housing and Urban Development nor any person acting in its behalf makes any warranty express or implied with respect to the use of any information apparatus method or process disclosed in this publication or that such use may not infringe privately owned rights or assumes any liabilities with respect to the use of or for damages resulting from the use of any information apparatus method or process disclosed in this publication or is responsible for statements made or opinions expressed by individual authors For Further Information Please consult the following websites for the latest version of this publication Plastics Pipe Institute httpwwwplasticpipeorg Plastic Pipe and Fittings Association httpwwwppfahomeorg ToolBaseorg httpwwwtoolbaseorg Table of Contents Chapter 1 INTRODUCTION 1 Objective 1 Background 1 Applications3 How to Use the Design Guide3 Chapter 2 ADVANTAGES 5 Ease of Installation5 Durability 5 Cost Effectiveness 5 Energy Efficiency5 Noise Reduction 6 Water Conservation6 Environmentally Sound6 Chapter 3 MATERIAL PROPERTIES 7 Temperature and Pressure 8 Flexibility8 Noise and Water Hammer Resistance8 Resistance to Freeze Damage9 Chlorine Resistance 9 Corrosion Resistance 10 Ultraviolet UV Resistance 10 Inert Material Safe for Drinking Water 11 PEX Piping Dimensions and Flow Characteristics11 Chapter 4 CODE ACCEPTANCE 15 International Residential Code IRC200315 International Plumbing Code IPC 200316 National Standard Plumbing Code NSPC 2003 17 Uniform Plumbing Code UPC200317 International Code Council ICC Evaluation Service Reports ESR and Evaluation Reports ER17 International Association of Plumbing and Mechanical Officials IAPMO Guide Criteria 18 C90406 American Waterworks Association ANSIAWWA C90406 18 Chapter 5 JOINING METHODS 19 Cold Expansion Fittings with PEX Reinforced Rings 20 Cold Expansion Fittings with Metal Compression Sleeves 20 Metal or Plastic Insert Fittings21 Copper Crimp Ring21 Stainless Steel Clamp 22 Stainless Steel Sleeve 22 Push Type Fittings 23 Standard Specifications for Fittings 24 ASTM F 1807 Standard Specification for Metal Insert Fittings Utilizing a Copper Crimp Ring for SDR9 CrossLinked Polyethylene PEX Tubing 24 ASTM F 1960 Standard Specification for Cold Expansion Fittings with PEX Reinforcing Rings for Use with Cross Linked Polyethylene PEX Tubing 24 ASTM F 2080 Standard Specification for Cold Expansion Fittings with Metal Compression Sleeves for Use with PEX Pipe 24 ASTM F 2098 Standard Specification for Stainless Steel Clamps for Securing SDR9 CrossLinked Polyethylene PEX Tubing to Metal Insert Fittings 24 ASTM F 2159 Standard Specification for Plastic Insert Fittings Utilizing a Copper Crimp Ring for SDR9 CrossLinked Polyethylene PEX Tubing 25 ASTM F 2434 Standard Specification for Metal Insert Fittings Utilizing a Copper Crimp Ring for SDR9 PEX Tubing and SDR9 PEXALPEX Tubing 25 IAPMO IGC 188 Removable and NonRemovable Push Fit Fittings 25 ASSE Standard 1061 25 Chapter 6 TYPES OF PEX PLUMBING SYSTEMS 27 Trunk and Branch 28 HomeRun 29 Remote Manifold 30 Chapter 7 DESIGN 31 Consult Local Codes 31 Optimize Home Designs 32 Select Piping System Design 33 General Rankings of the Systems for Key Factors 34 Example Layouts 35 Colonial Layout 36 Ranch Layout 39 Townhouse Layout 42 Condominium Layout 45 Performance Verification Laboratory Testing 48 Industry Technical Support 48 Plan Pipe Routing Manifold and Valve Locations 48 Chapter 8 PERFORMANCE DATA 51 System Performance Comparison51 Test System Design and Setup 51 Plumbing System Pressure and Flow Test Results 54 Wait Time for Hot Water61 Test Summary 62 Chapter 9 INSTALLATION 63 Important Notice 63 Revision Policy 64 Manual Content Use 65 Parallel Water Distribution Manifold Plumbing HomeRun Protection of Tubing and Fittings from UV Exposure after the Insert Fitting with a Black Copper Crimp Ring Joining Procedures Utilizing ASTM F 1960 Fittings and Other Uses of CrossLinked Polyethylene PEX Tubing 65 Tubing Identification 66 Fitting Identification 67 Applicable Standards 67 Limitations on PEX Use 67 TUBING INSTALLATION PRACTICES 68 General Installation 68 Bending the Tubing 69 Handling and Storing Tubing and Fittings 69 Tubing Supports 70 Selection and Inspection 70 Support Spacing and Location 70 Horizontal Tubing Support Spacing 70 ExpansionContraction of Tubing71 Hydraulic Shock Pressure Surge 71 Manifold Plumbing Systems 72 Systems 73 Thawing PEX Tubing Systems 75 Pressure Testing and Inspection of the Completed System 76 Disinfection of Potable Water Systems 76 Buried PEX Water Service Lines 77 Fittings 77 Trench Preparation 77 Laying the Tubing 77 Penetrating Foundation or Basement Walls 77 SlabonGrade Installation 78 Laying and Supporting Tubing under Slab 78 Pour 78 Backfilling 78 Technical Data 79 Tubing Dimensions and Weights ASTM F 876F 877 79 Friction Losses 79 Friction Loss and Velocity vs Flow Rate 80 PEX Plumbing Tubing CTS ASTM F 876F 877 80 Connection Transition to Other Piping Materials 81 Joining Procedures Utilizing Metallic or Polymer Insert Fittings 81 ASTM F 1807 OR ASTM F 2159 81 Making a Connection 81 Incorrect Connections 81 Tools and Rings 82 PEX Rings 82 ASTM F 1960 Connections Helpful Hints 83 Tools 84 Joining Procedures utilizing ASTM F 2080 Fittings and Compression Sleeves 84 Summary 84 Procedure 84 Other Fitting Systems 85 Chapter 10 TESTIMONIALS 87 Chapter 11 OTHER APPLICATIONS 91 Radiant Floor Heating Systems 91 Municipal Water Service Pipe91 Snow and Ice Melt 92 Turf Conditioning 92 Fire Suppression 93 Appendix A PERFORMANCE TEST SETUP AND DATA 95 Appendix B INSTALLATION CHECKLIST 105 Appendix C RESOURCES 107 Articles and Reports 107 Manufacturers Information 111 Plastics Pipe Institute PPI Technical Notes 113 GLOSSARY 115 List of Figures Figure 51 Cold Expansion Polymer Fitting with PEX Reinforced Ring 20 Figure 52 Cold Expansion Metal Fitting with PEX Reinforced Ring 20 Figure 53 Cold Expansion Fitting with Metal Compression Sleeve 20 Figure 54 Metal Insert Fitting with Copper Crimp Ring 21 Figure 55 Plastic Insert Fitting with Copper Crimp Ring 21 Figure 56 Metal Insert Fitting with Orings and Copper Crimp Ring 21 Figure 57 Metal Insert Fitting with Stainless Steel Clamp Band 22 Figure 58 Metal Insert Fitting with Stainless Steel Clamp Sleeve 22 Figure 59 Metal Insert Fitting with Stainless Steel Press Sleeve 22 Figure 510 Push Type Fitting 23 Figure 61 PEX Pipes in a Trunk and Branch System Design 28 Figure 62 PEX Pipes in a HomeRun Design 29 Figure 63 PEX Pipes in a Remote Manifold Design 30 Figure 71 Trunk and Branch Isometric Riser for the Colonial House 37 Figure 72 HomeRun Isometric Riser for the Colonial House 37 Figure 73 Remote Manifold Isometric Riser for the Colonial House 38 Figure 74 Trunk and Branch Isometric Riser for the Ranch House 40 Figure 75 HomeRun Isometric Riser for the Ranch House 40 Figure 76 Remote Manifold Isometric Riser for the Ranch House 41 Figure 77 Trunk and Branch Isometric Riser for the Townhouse 43 Figure 78 HomeRun Isometric Riser for the Townhouse 43 Figure 79 Remote Manifold Isometric Riser for the Townhouse 44 Figure 710 Trunk and Branch Isometric Riser for the Condominium 46 Figure 711 HomeRun Isometric Riser for the Condominium 46 Figure 712 Remote Manifold Isometric Riser for the Condominium 47 Figure 81 Fixture Layout for Laboratory Testing 52 Figure 82 Laboratory Test Setup with Five Outlets Hot Water Tank and TB System 53 Figure 83 The Test Fixture Shower with Flow and Pressure Sensors Installed 53 Figure 84 Pressure Drop Comparison 100 Distance to TF 60 Figure 85 Pressure Drop Comparison 60 Distance to TF 60 Figure 86 Comparison of Hot Water Delivery Time 61 Figure 111 Radiant Floor Heating Piping 91 Figure 112 Snow and Ice Melt Piping for a Driveway 92 Figure 113 Turf Conditioning in a Stadium 92 Figure 114 Fire Sprinkler with PEX Piping 93 Figure A1 Water System Test Piping Layout Trunk and Branch 60 to TF 95 Figure A2 Water System Test Piping Layout Trunk and Branch 100 to TF 96 Figure A3 Water System Test Piping Layout HomeRun 60 to TF 96 Figure A4 Water System Test Piping Layout HomeRun 100 to TF 97 Figure A5 Water System Test Piping Layout Remote Manifolds 60 to TF 97 Figure A6 Water System Test Piping Layout Remote Manifolds 100 to TF 98 1 10 List of Tables Table 31 PEX Pipe Dimensions11 Table 32 Flow Velocity12 Table 33 Pressure Loss 13 Table 71 General Rankings of the System Characteristics 34 Table 72 Fixture Count for each House Type 35 Table 73 Fixture Summary for the Colonial House 36 Table 74 Material Summary for the Colonial House 36 Table 75 Fixture Summary for the Ranch House 39 Table 76 Material Summary for the Ranch House 39 Table 77 Fixture Summary for the Townhouse 42 Table 78 Material Summary for the Townhouse 42 Table 79 Fixture Summary for the Condominium 45 Table 710 Material Summary for the Condominium 45 Table 81 Plumbing Fixtures Installed in the Test Plumbing System 54 Table 82 Pressure and Flow Test Regime 54 Table 83 TF Flow and Pressure Data for Each System 55 Table 84 Simultaneous Flow Performance Data 100 Maximum Length 40 psi Source Pressure 56 Table 85 Simultaneous Flow Performance Data 60 Maximum Length 40 psi Source Pressure 58 Table 86 Performance Summary 100 Maximum Distance 62 Table A1 Simultaneous Flow Performance Data 100 Maximum Length 60 and 80 psi Source Pressure 98 Table A2 Simultaneous Flow Performance Data 60 Maximum Length 60 and 80 psi Source Pressure 101 10 1 InTroduCTIon Objective This Design Guide provides the information and resources necessary to design and install crosslinked polyethylene PEX water supply systems in residential buildings It includes comprehensive design concepts and installation guidelines to increase the acceptance and proper use of PEX This document is targeted to meet the needs of home builders designers and trade contractors Its purpose is to introduce potential users to PEX and to enable current users to optimize their PEX plumbing and minimize system costs In addition it will allow code inspectors and homeowners to become familiar with the applications performance characteristics and benefits of PEX water supply systems Background Crosslinked polyethylene PEX is a hightemperature flexible polymer pipe Crosslinking technology was first developed in Europe and has since come into use around the world for a variety of applications PEX has a 30year history of successful use in the European market with extensive testing for durability and material performance It was first introduced in North America in 1984 where it has been primarily used for radiant floor heating and more recently for domestic water distribution systems It is approved for potable hot and cold water supply systems as well as hydronic heating systems in all model plumbing and mechanical codes across the United States and Canada The comparison of PEX to polybutylene piping PB appears to be a major obstacle to mainstream acceptance by some code officials trade contractors and homeowners But not all plastics are the same just as not all metals are the same Polymer fittings for PEX pipe are far more robust and reliable than those used for PB A result of modern polymer technology PEX piping performs in ways that provide superior reliability durability and safety Also current testing requirements for PEX are much more stringent than when PB piping was accepted and installed in housing 1 3 2 Chapter 1 InTroduCTIon The PEX piping industry is highly regulated Standards specifications and code requirements define tight material and production quality controls Continuoususe temperature ratings as high as 200ºF 93ºC are required as well as standardized chlorine resistance testing to ensure that the piping will withstand the most aggressive drinking water conditions Nationally accredited thirdparty certification agencies require strenuous quality control testing including random plant inspections and annual monitoring testing There are numerous opportunities for more widespread use of PEX pipe in the US residential market The development of manifolds and parallel plumbing systems for flexible piping has helped to advance its use All major residential building codes permit the use of PEX piping but obstacles to its acceptance still remain There is anecdotal and research information that shows Some plumbers are reluctant to use PEX piping due to a lack of experience with installation methods and design requirements Some jurisdictions prohibit the use of PEX piping for water supply plumbing even though PEX pipe is approved for use in all model codes Codes were originally written for rigid trunk and branch systems while they have now been amended to include PEX piping systems they do not provide many system design details There is a perception among some that PEX piping systems are inferior as a building product generally based on knowledge of past failures of PB piping systems Although these hurdles exist the following are among the many benefits of PEX piping systems Ease of Installation PEX pipe uses mechanical connections eliminating the need for solders flames and chemicals Its flexible nature allows it to bend around obstructions Use of manifolds can speed installation and improve performance Corrosion Resistance PEX piping will not pit or stress corrode Scaling Resistance PEX pipes smooth interior walls and chemical properties make it resistant to mineral buildup Cost Effectiveness PEX plumbing systems are less labor intensive and can optimize system performance Availability of Pipe Sizes PEX piping is available in a wide range of diameters Energy Efficiency PEX piping minimizes heat transmission through the pipe wall Resistance to Freeze Damage Under most circumstances water in the pipe can be frozen and thawed without damaging the pipe Water Conservation Well designed PEX plumbing systems can reduce the wait time for hot water to reach the fixture Environmentally Sound PEX is an inert material and does not contain volatile organic compounds VOCs Certification PEX pipes and fittings must meet strict performance requirements 2 2 3 Chapter 1 InTroduCTIon Although general research on hot water systems has been performed on various aspects of plumbing systems a recent literature search by the NAHB Research Center indicated that specific system design information for flexible water supply plumbing is sparse Documents relied more on standard practice than on engineered or designed systems Using these approaches often leads to system designs that either supply more water than is needed at the fixture or do not take advantage of the characteristics of a flexible plumbing system to reduce cost and improve performance This Design Guide provides the information and resources necessary to design and install efficient and costeffective PEX water supply systems in residential buildings It illustrates various plumbing configurations for a variety of house types as well as installation guidelines for each method Properly designed and installed PEX piping systems are beneficial for plumbing designers installers and homeowners Applications PEX piping can be used in a wide variety of applications in residential construction This Design Guide is focused on the design and installation of PEX hot and cold water supply systems which can be used for both new construction and remodeling projects Other applications for PEX are described in a separate section of this guide and include Radiant floor heating systems for suspended floor systems or in slab construction Municipal water service pipe in underground applications Snow and ice melt systems for sidewalks driveways entrances and ramps Turf conditioning for greenhouses golf courses and sports field surfaces Fire suppression systems residential fire sprinklers Available in sizes from 14 to 2 inches PEX piping can generally be installed in place of rigid piping on a sizeforsize basis Homerun installations with central manifolds can be used to balance pressures at the outlets and minimize hot water delivery wait time reducing wasted water and energy Manifolds can be installed that reduce the amount of piping and fittings speedup installation and balance pressures throughout the system How to Use the Design Guide This PEX Design Guide can be used by anyone considering the installation of PEX piping for a residential plumbing system It can be used by the novice as an introduction to PEX piping or by the experienced plumber to optimize hisher approach Building code officials can use this Guide as a consolidated source of information on the application of PEX piping in residential buildings Builders can use this guide to learn about the advantages installation issues and expected performance of PEX plumbing systems for discussions with sales staff and homeowners 3 55 4 Chapter 1 InTroduCTIon Each section of this guide focuses on various aspects of using PEX piping Chapter 1 Introduction Background information to educate the user about the history and uses of PEX piping Chapter 2 Advantages Various advantages to using PEX piping in residential buildings Chapter 3 Material Properties Unique properties of PEX piping Chapter 4 Joining Methods Explanations of the various types of fittings and their joining methods Chapter 5 Types of PEX Plumbing Systems Descriptions of the three types of PEX piping system designs Chapter 6 Code Acceptance Information on major plumbing codes and relevant jurisdictional code provisions for PEX piping Chapter 7 Design Designs and performance details of the three basic plumbing layouts for four common house configurations to assist in evaluating which system provides the best balance of performance ease of installation and cost for a particular house Chapter 8 Lab Testing and Performance Data System performance comparison of three plumbing systems Chapter 9 Installation Detailed instructions for installing PEX piping Chapter 10 Testimonials Quotes from plumbers and home builders on their experiences with PEX piping Chapter 11 Other Applications Other uses of PEX piping Appendix A Additional lab testing data Appendix B New Installation Checklist to aid plumbers with the process of installing PEX piping Appendix C Resources for additional information beyond this Design Guide Glossary List of terms and acronyms used in this Design Guide There are three main ways to use this guide Introductory Overview The guide can be read in its entirety as an introduction for those who have little or no exposure to PEX piping Planning Tool The Code Acceptance and Design chapters in particular can be used to optimize system designs and building layouts during the planning stage while the home design is being finalized Reference Guide Certain sections can be extracted and read as needed For example plumbers may want to reference the Installation section or building inspectors may want to reference the Code Acceptance section 4 44 5 2 AdVAnTAGES Ease of Installation The installation of PEX pipe is generally easier than rigid pipe It is available in long coils which eliminates the need for coupling joints Its flexible nature allows it to be bent gently around obstructions minimizing the use of fittings No solvent chemical or solder joining is required The mechanical fittings are secure and reliable when installed properly The pipe is lightweight making it safe to transport and easy to handle For a comparison of the installation of rigid metal pipe to PEX pipe refer to the PATH Field Evaluation in Lincoln Neb1 Durability Based on extensive testing and material performance over the span of more than 30 years PEX piping has proven to be a durable material that does not suffer from some of the historical problems associated with metallic piping such as reduced interior dimension corrosion electrolysis filming mineral buildup and water velocity wear PEX piping will typically expand if the system is allowed to freeze and return to its original size when the water thaws Cost Effectiveness PEX plumbing systems have lower installation costs than rigid metallic plumbing systems Installation time and labor required is greatly reduced In service the use of PEX systems can reduce energy and water use by delivering water to the fixtures faster and by reducing losses in the piping Energy Efficiency PEX piping offers reduced heat loss and improved thermal characteristics when compared to metallic pipe In addition less energy is used by the water heater because of shorter delivery time for hot water with PEX parallel plumbing systems2 1 The full PATH Field Evaluation report is available at httpwwwtoolbaseorg 2 Evaluation of Hot Water Distribution Systems by Numeric Simulation 2004 Building Technology Center Oak Ridge National Laboratory 5 77 6 Chapter 2 AdVAnTAGES Noise Reduction When properly secured PEX piping can be significantly quieter than rigid systems It is inherently less noisy due to its flexibility and ability to absorb pressure surges Water Conservation Properly designed PEX plumbing systems have the potential to conserve water see Chapters 5 and 7 The flexibility of PEX allows it to bend around corners and run continuously reducing the need for fittings this allows downsizing the pipe diameter to 38inch for certain fixtures Homerun systems and 38inch pipes minimize the time it takes hot water to reach the fixture Lengthy delivery time for hot water represents a significant waste of water as well as energy a problem exacerbated in larger homes In 2002 the NAHB Research Center conducted software simulations and laboratory tests on a typical hot water system using a trunk and branch rigid pipe design and one that included a 38inch diameter PEX homerun system Results indicated that systems using shorter 38inch runs with a homerun manifold reduced the wait time for hot water and wasted less water than longer runs of rigid pipe with many elbows and connections3 Environmentally Sound PEX is a modification or enhancement of highdensity polyethylene an economical and highly costeffective construction piping material Generally manufacturing equivalent lengths of plastic pipe consumes far less energy than manufacturing metallic pipe The lighter weight of PEX compared to metallic piping helps to lower transportation costs and energy consumption offering even greater benefit PEX pipes can be recycled as an inert filler material that can be incorporated into other polymers for specific applications There is also reduced water use through faster delivery time In addition PEX pipe does not contain harmful VOCs 3 Performance Comparison of Residential Hot Water Systems November 2002 NAHB Research Center report available at httpwwwtoolbaseorg 6 66 7 3 MATErIAL ProPErTIES PEX is a material made up of molecules of highdensity polyethylene HDPE that are permanently linked to each other by a process called crosslinking Crosslinking makes PEX a thermoset polymer which gives it longterm stability Polyethylene can be crosslinked using several technologies All methods induce links between the single strands of PE to form a dense network through radical reactions The number of links between the strands determines the crosslink density and is an important factor in determining the physical properties of the material The minimum percent crosslinking for each method is specified in the ASTM F 876 standard The three most common methods of crosslinking polyethylene are as follows Peroxide Peroxides are heatactivated chemicals that generate free radicals for crosslinking This is called the Engel Process Moisturecured Vinylsilane This method involves grafting a reactive silane molecule to the backbone of the polyethylene This is called the Silane Process Beta Irradiation This method involves subjecting a dose of highenergy electrons to the PE This is called the Radiation Process In European standards these three methods are referred to as PEXA PEXB and PEXC respectively and are not related to any type of rating system PEX pipe produced by any of the three methods must meet the same qualification requirements as specified in the PEX standards Although methods of crosslinking produce different characteristics all three methods have been utilized to manufacture approved PEX products As required in any manufacturing process procedures for each technology must be established and followed with good quality control checks in place to produce quality products 7 9 8 Chapter 3 MATErIAL ProPErTIES Temperature and Pressure PEX piping meets all requirements for pressure and temperature performance in residential applications Consensus standards published by the American Society for Testing and Materials ASTM International specify temperature and pressureresistant capabilities of PEX pipe and all tubing used in residential applications bears the appropriate test marking In the event of a water heating system malfunction PEX piping is designed to accommodate shortterm conditions of 48 hours at 210ºF 99ºC and 150 psi 1034 kPa until repairs can be made The most commonly used safety relief valve TP activates opens at either of these temperature or pressure conditions All PEX piping has been tested to withstand TP activation for 30 days to ensure that safety requirements are met As such PEX systems DO NOT require the use of a special TP valve ASTM F 876 Standard Specification for CrossLinked Polyethylene PEX Tubing covers PEX piping that is outside diameter controlled and pressure rated for water at three temperatures160 psi 734ºF 100 psi 180ºF and 80 psi 200ºF Included are requirements and test methods for material workmanship dimensions hydrostatic sustained pressure strength burst pressure oxidative chlorine resistance and environmental stress cracking ASTM F 877 Standard Specification for CrossLinked Polyethylene PEX Plastic Hot and Cold Water Distribution Systems covers requirements and test methods for PEX hot and coldwater distribution system components made in one standard dimension ratio and intended for 100 psi water service up to and including a maximum working temperature of 180ºF Components are comprised of piping and fittings Requirements and test methods are included for hydrostatic sustained pressure strength thermocycling resistance fittings and bend strength Flexibility The flexible nature of PEX allows it to be bent gently around obstructions and installed as one continuous run without fittings Slight changes in direction are made easily by bending the pipe by hand There is a predetermined bend radius of a 90degree change of direction without installing a fitting reference manufacturers installation instructions Minimizing mechanical connections can result in quicker installations less potential for leaks at fittings and less resistance due to pressure drops through fittings Noise and Water Hammer Resistance As water flows through pipes pressure in the system gives moving water energy known as kinetic energy Kinetic energy increases with the speed of water and also with the mass of water that is flowing When the flow of water is stopped such as when a valve or faucet is closed this kinetic energy must be dissipated in the system The ability of a plumbing pipe to dissipate energy due to surge in water pressure is based on the pipes modulus of elasticity a measure of material stiffness A higher modulus of elasticity means the material is more rigid Copper pipe is 180 times more rigid than PEX pipe Ultimately this means that with rigid piping systems pressure surges can produce noticeable banging sounds as energy is dissipated thus causing what is known as water hammer The pressure surge that causes water hammer can produce instantaneous pressures of 300 to 400 psi 2070 to 2760 kPa which can cause damage to rigid pipes fittings and connections 8 8 9 Chapter 3 MATErIAL ProPErTIES The flexibility of PEX pipe allows the pipe itself to absorb energy from pressure surges and eliminate or reduce the occurrence of water hammer Resistance to Freeze Damage PEX pipes are less susceptible to the effects of cold temperatures retaining their flexibility even below freezing This flexibility means that if waterfilled PEX piping freezes the elasticity of the material allows it to expand without cracking or splitting and then to return to its original size upon thawing This applies when PEX pipes have room to expand evenly along their length as is typical when installed within walls or ceilings PEX pipes inside a slab may not be able to expand evenly Chlorine Resistance The US Environmental Protection Agency EPA recommends that all drinking water be disinfected typically using free chlorine chloramines or other less common methods Currently the majority of potable drinking water in the United States and Canada is disinfected using free chlorine For water treated with free chlorine the EPA sets a maximum disinfectant level of 40 parts per million ppm within the water distribution system The secondmost common disinfectant is chloramines Research conducted by Jana Laboratories at the request of the Plastics Pipe Institute PPI indicates that free chlorine is generally more aggressive to crosslinked polyethylene PEX pipes than chloramines To ensure the reliability of PEX piping systems in hot chlorinated water applications it is a requirement of the PEX pipe product standard specification ASTM F 876 that all PEX pipes intended for use with potable water have a minimum extrapolated lifetime of 50 years when tested in accordance with test method ASTM F 2023 Standard Test Method for Evaluating the Oxidative Resistance of Crosslinked Polyethylene PEX Tubing and Systems to Hot Chlorinated Water The minimum requirement applies to traditional domestic applications4 The test conditions of ASTM F 2023 require that the test fluid has a minimum oxidative reduction potential ORP of 825 mV To produce test fluid with this high ORP thirdparty test laboratories typically use reverse osmosispurified water with a free chlorine concentration of 43 03 ppm 43 mgL and pH of 68 02 resulting in an ORP of 825 mV or higher This represents a very aggressive water quality which gives conservative results This test procedure is designed to extrapolate the life expectancy of a hotwater plumbing pipe when used at a water temperature of 140F and a pressure of 80 psi Continuous recirculation and traditional domestic4 conditions can both be evaluated by ASTM F 2023 PEX pipe manufacturers must have pipes tested and certified by NSF International UL andor other thirdparty certification agencies to meet the requirements of ASTM F 876 including chlorine resistance In addition manufacturers may have pipes certified to NSF International protocol P 171 Chlorine Resistance of Plastic Piping Materials PEX piping systems use fittings that also must comply with ASTM standards and are made from brass copper or high temperature engineered polymers that are chlorineresistant In summary PEX pipe has shown itself to be resistant to attack from chlorine and chloramines under a wide range of conditions and has performed reliably in all regions of North America 9 4 Traditional domestic applications are defined in ASTM F 2023 as piping systems which operate for up to 25 percent of the service time at a water temperature of 140F 60C and 75 percent of the time at ambient room temperatures A plumbing system with more demanding water quality conditions than those listed above should be discussed with the PEX piping manufacturer before installation 11 11 10 Chapter 3 MATErIAL ProPErTIES Corrosion Resistance PEX pipe and fittings have been tested extensively with aggressive potable water conditions and did not pit or corrode PEX pipe and fittings are tested with corrosive pH levels between 65 and 67 much lower and more aggressive than levels found in common water systems A related aspect of corrosion in pipes is concerned with flow erosion Flow erosion tests of PEX fittings were conducted by the PPI High Temperature Division HTD See Erosion Study on Brass Insert Fittings Used in PEX Piping Systems PPITN26 for discussion and results Ultraviolet UV Resistance Like most plastics the longterm performance of PEX will be affected by UV radiation from sunlight Although most PEX pipes have some UV resistance PEX pipes should not be stored outdoors where they are exposed to the sun Precautions must be taken once the pipe is removed from the original container Each PEX pipe manufacturer publishes a maximum recommended UV exposure limit based on the UV resistance of that pipe Do not allow PEX pipes to be overexposed beyond these limits PEX pipes should not be installed outdoors unless they are buried in earth or properly protected from UV exposure either direct or indirect Indirect diffused and reflected sunlight also have UV energy If PEX will be exposed to sunlight continuously after installation such as in an unfinished basement cover the pipe with a UVblocking sleeve black preferred or approved pipe insulation Different manufacturers pipes have different degrees of UV resistance as indicated on their labels always follow the recommendations provided by the particular manufacturer See PPI UV Labeling Guidelines for PEX Pipes TN32 Caution Do not store PEX pipes outdoors Keep PEX pipes in original packaging until time of installation Ensure that exposure to sunlight during installation does not exceed the maximum recommended UV exposure time as recommended by the manufacturer 10 10 10 11 Chapter 3 MATErIAL ProPErTIES Inert Material Safe for Drinking Water Since PEX piping is used to transport potable water it must comply with federal regulations for public safety PEX materials are inert not chemically reactive and cannot contaminate the potable water passing through them The fittings are mechanical and do not require the use of solvents or chemicals that might leach into the water when the system is first used Testing and certification must comply with NSFANSI Standard 61 Drinking Water System Components Health Effects and Standard 14 Plastic Pipe System Components and Related Materials The primary focus of Standard 61 is to establish minimum health effect requirements for chemical contaminants and impurities that are indirectly imparted into drinking water from products components and materials used in potable water systems PEX piping systems are tested at water pH levels from 50 to 100 both excessive acidity and alkalinity beyond levels encountered in potable water systems PEX pipe does not corrode and it is resistant to mineral buildup NSFANSI Standard 14 covers physical performance and health effect requirements for plastic piping system components used in potable hot and coldwater distribution systems PEX Piping Dimensions and Flow Characteristics Table 31 PEX Pipe Dimensions Nominal Diameter OD Wall ID Weight inches1 inches2 inches lbft 38 0500 0075 0350 005 12 0625 0075 0475 006 34 0875 0102 0671 010 1 1125 0130 0865 016 1 14 1375 0160 1055 025 1 12 1625 0190 1245 035 2 2125 0248 1629 060 1 Average OD from ASTM F 876 2 Average wall thickness from ASTM F 876 11 13 13 12 Chapter 3 MATErIAL ProPErTIES Table 32 Flow Velocity Flow Rate ftsec GPM 38 12 58 34 1 1 14 1 12 2 02 067 036 025 018 011 007 005 003 03 100 054 037 027 016 011 008 005 04 133 072 050 036 022 015 011 006 05 167 091 062 045 027 018 013 008 06 200 109 074 054 033 022 016 009 07 233 127 087 064 038 026 018 011 08 267 145 099 073 044 029 021 012 09 300 163 112 082 049 033 024 014 10 333 181 124 091 055 037 026 015 11 367 199 136 100 060 040 029 017 12 400 217 149 109 066 044 032 018 13 434 235 161 118 071 048 034 020 14 467 253 174 127 076 051 037 022 15 500 272 186 136 082 055 040 023 16 534 290 198 145 087 059 042 025 17 567 308 211 154 093 062 045 026 18 600 326 223 163 098 066 047 028 19 634 344 236 172 104 070 050 029 20 667 362 248 181 109 073 053 031 25 834 453 310 227 136 092 066 038 30 1000 543 372 272 164 110 079 046 35 1167 634 434 318 191 128 092 054 40 724 496 363 218 147 105 062 45 815 558 408 246 165 119 069 50 905 620 454 273 184 132 077 60 1086 744 544 328 220 158 092 70 868 635 382 257 184 108 80 992 726 437 294 211 123 90 1116 817 491 330 237 139 12 12 12 13 Chapter 3 MATErIAL ProPErTIES Table 32 Flow Velocity continued Flow Rate ftsec GPM 38 12 58 34 1 1 14 1 12 2 100 907 546 367 264 154 110 998 601 404 290 169 120 1089 655 440 316 185 130 710 477 343 200 140 764 514 369 216 150 819 551 395 231 Table 33 Pressure Loss 60F 16C Water Flow Rate Pressure Loss psi100 ft of Pipe GPM 38 12 58 34 1 1 14 1 12 2 02 0427 0099 0040 0019 0006 0002 0001 00003 03 0880 0204 0083 0039 0012 0005 0002 0001 04 1470 0341 0138 0065 0019 0008 0003 0001 05 2189 0508 0205 0097 0029 0011 0005 0001 06 3032 0703 0284 0135 0040 0015 0007 0002 07 3993 0926 0374 0177 0053 0020 0009 0003 08 5069 1175 0475 0225 0067 0026 0012 0003 09 6258 1450 0586 0278 0082 0032 0014 0004 10 7555 1751 0707 0335 0099 0038 0017 0005 11 8960 2076 0839 0397 0118 0046 0021 0006 12 1047 2425 0980 0464 0138 0053 0024 0007 13 1208 2799 1131 0535 0159 0061 0028 0008 14 1380 3195 1291 0611 0181 0070 0032 0009 15 1561 3615 1460 0691 0205 0079 0036 0010 16 1752 4058 1639 0776 0230 0089 0040 0011 17 1953 4523 1827 0865 0256 0099 0045 0012 18 2164 5010 2023 0958 0284 0110 0050 0014 13 15 15 14 Chapter 3 MATErIAL ProPErTIES Table 33 Pressure Loss continued 60F 16C Water Flow Rate Pressure Loss psi100 ft of Pipe GPM 38 12 58 34 1 1 14 1 12 2 19 2384 5519 2229 1055 0313 0121 0055 0015 20 2614 6050 2443 1157 0343 0133 0060 0017 25 3900 9024 3643 1724 0511 0197 0089 0025 30 5410 1251 5050 2390 0708 0274 0124 0034 35 7136 1650 6658 3150 0933 0360 0163 0045 40 2097 8459 4002 1185 0458 0207 0057 45 2590 1045 4943 1463 0565 0256 0071 50 3130 1263 5972 1768 0683 0309 0085 60 4344 1752 8284 2451 0946 0428 0118 70 2311 1093 3232 1248 0564 0156 80 2938 1389 4108 1585 0717 0198 90 3632 1717 5076 1959 0885 0244 100 2075 6134 2367 1070 0295 110 2463 7281 2808 1269 0350 120 2881 8514 3284 1484 0409 130 9832 3792 1713 0472 140 1124 4332 1957 0539 150 1272 4905 2216 0610 Shown is pressure loss in units of psi per 100 feet of pipe 14 14 14 15 4 CodE ACCEPTAnCE PEX plumbing systems are recognized in all major building model codes and are commonly used for hot and coldwater distribution applications water service lines and radiant floor heating systems The following is a summary of relevant model code requirements which specifically pertain to PEX and plastic pipe and fittings used for domestic water supply i i li l is i l li i l l l i l i ly pipi i The user must determ ne wh ch codes are app cab e to h her spec fic project and a so must ensure comp ance w th a l loca state and federal codes regu at ons and standards Codes are constant y rev ewed and updated PEX water supp ng has been adopted in the model codes s nce 1993 International Residential Code IRC2003 P2605 Support P26051 General Piping shall be supported at distances not to exceed those indicated in Table 26051 For PEX maximum horizontal support spacing is 32 inches and maximum vertical support spacing is 10 feet midstory guide for sizes 2 inches and smaller P26083 Plastic Pipe Fittings and Components All plastic pipe fittings and components shall be thirdparty certified as conforming to NSF 14 P29038 Parallel WaterDistribution System Manifolds Hot and cold parallel water distribution system manifolds with individual distribution lines to each fixture or fixture fitting shall be sized and installed in accordance with Sections P290381 through P290387 15 17 17 16 Chapter 4 CodE ACCEPTAnCE P290381 Sizing of Manifolds Manifolds shall be sized in accordance with Table P290381 A maximum gallon per minute gpm is specified for different nominal inside diameter sizes for plastic and metallic manifolds P290383 Maximum Length The maximum length of individual distribution lines shall be 60 feet 182 m nominal P290385 Support and Protection Plastic piping bundles shall be secured in accordance with manufacturers installation instructions and supported in accordance Section P2605 Bundles that have a change in direction equal to or greater than 45 degrees shall be protected from chaffing at the point of contact with framing members by sleeving or wrapping P29045 Water Distribution Pipe References Table P29045 PEX plastic tubing shall conform to ASTM F 877 and CSA B1375 standards P2904914 Crosslinked Polyethylene Plastic PEX References Section P29049141 or Section P2904142 P29049142 Mechanical Joints Mechanical joints shall be installed in accordance with manufacturers instructions Fittings for PEX plastic tubing as described in ASTM F 1807 ASTM F 1960 ASTM F 2080 and ASTM F 2159 shall be installed in accordance with manufacturers instructions P2904162 Plastic Pipe or Tubing to Other Pipe Materials Joints between different grades of plastic pipe or between plastic pipe and other piping material shall be made with an approved adapter fitting International Plumbing Code IPC 2003 6053 Water Service Pipe Water service pipe shall conform to NSF61 and shall conform to one of the standards listed in Table 6053 ASTM F 876 ATM F 877 and CSAB1375 6054 Water Distribution Pipe Water distribution pipe shall conform to NSF 61 and shall conform to one of the standards listed in Table 6054 ASTM F 877 and CSAB1375 6055 Fittings Pipe fittings shall be approved for installation with the piping material installed and shall conform to one of the standards listed in Table 6055 ASTM F 1807 ASTM F 1960 and ASTM F 2080 60517 Crosslinked Polyethylene Plastic Joints between crosslinked polyethylene plastic tubing or fittings shall comply with Sections 605171 and 605172 605173 Mechanical Joints Mechanical joints shall be installed in accordance with manufacturers instructions Fittings for PEX tubing as described in ASTM F 1807 ASTM F 1960 and ASTM F 2080 shall be installed in accordance with manufacturers instructions 605232 Plastic Pipe or Tubing to Other Piping Material Joints between different grades of plastic pipe or between plastic pipe and other piping material shall be made with an approved adapter fitting 16 16 16 17 Chapter 4 CodE ACCEPTAnCE National Standard Plumbing Code NSPC 2003 341 Plastic Piping Plastic piping materials used for the conveyance of potable water shall comply with NSF 14 and be marked accordingly 342 Water Service Piping Water service piping to the point of entrance into the building shall be of materials listed in Table 34 and shall be water pressure rated for not less than 160 psig at 73F Table 34 PEX Plastic Water Distribution Systems ASTM F 877 with ASTM F 1807 F 1960 or F 2098 Fittings 343 Water Distribution Piping Water piping for distribution of hot and cold water within buildings shall be of materials listed in Table 34 and shall be water pressure rated for not less than 100 psig at 180F Plastic piping used for hot water distribution shall be installed in accordance with requirements of Section 10158 NOTE The working pressure rating for certain approved plastic piping materials varies depending on pipe size pipe schedule and methods of joining 10158 Plastic Piping Plastic piping used for hotwater distribution shall conform to the requirements of Section 34 and Table 34 Piping shall be water pressure rated for not less than 100 psi at 180F NOTE The working pressure rating for certain approved plastic piping materials varies depending on pipe size pipe schedule and methods of joining Plastic pipe or tube shall not be used downstream from instantaneous water heaters immersion water heaters or other heaters not having approved temperature safety devices Piping within 6 inches of flue or vent connectors shall be approved metallic pipe or tube Normal operating pressure in water distribution piping systems utilizing approved plastic pipe or tube for hot water distribution shall not be more than 80 psi Uniform Plumbing Code UPC2003 60411 PEX Crosslinked polyethylene PEX tubing shall be marked with the appropriate standard designations see Chapter 9 for which the tubing has been approved PEX tubing shall be installed in compliance with the provisions of this section 604111 PEX Fittings Metal insert fittings metal compression fittings and cold expansion fittings used with PEX tubing shall be manufactured to and marked in accordance with the standards for the fittings see Chapter 9 604112 Water Heater Connections PEX shall not be installed within the first 18 inches 457 mm of piping connected to a water heater International Code Council ICC Evaluation Service Reports ESR and Evaluation Reports ER International Code CouncilEvaluation Service ICCES conducts technical evaluations of building products components methods and materials The evaluation process culminates with issuance of technical reports that because they directly address code compliance are useful to both regulatory agencies and buildingproduct manufacturers Agencies use evaluation reports to determine code compliance and enforce building regulations manufacturers use 17 19 19 18 Chapter 4 CodE ACCEPTAnCE reports as evidence that their products meet code requirements and warrant regulatory approval Several PEX manufacturers have ESRs or ERs Evaluation Reports can be obtained from wwwiccesorg International Association of Plumbing and Mechanical Officials IAPMO Guide Criteria The IAPMO Guide Criteria IGC procedure provides manufacturers and product developers an opportunity to draft IAPMO standards as a vehicle for introducing new products when no applicable standard exists for the product Once an IGC is accepted IAPMO can list products manufactured in compliance with the new requirements Some PEX and PEX fitting manufacturers have products listed under IGCs Lists of IGCs can be obtained from wwwiapmoorg C90406 American Waterworks Association ANSIAWWA C90406 This standard describes PEX pressure pipe made from material having a standard PEX material designation code of PEX 1006 in ASTM F 876 for use as underground water service lines in sizes 12 inch through 3 inches and conform to a standard dimension ration of SDR9 Included in this standard are criteria for classifying PEX plastic pipe materials and a system of nomenclature requirements and test methods for materials and pipe Methods of marking are given Design installation and application considerations are discussed in the forward of this standard 18 18 18 19 5 JoInInG METHodS There are several types of joining methods or fittings used with PEX plumbing systems All are mechanical fittings that are either directional or transitional PEX piping cannot be joined by solvent cementing Most PEX piping manufacturers have their own mechanical fitting system The method of connection should comply with the manufacturers recommendations and instructions Fittings are regulated to comply with performance and material criteria from recognized standards They should be marked by a certified thirdparty agency such as NSF IAPMO CSA IGC UL or other thirdparty testing and listing agency l i li le wi l i l le Not a l fitt ngs are app cab th a l PEX p pe Consu t your manufacturer for acceptab methods The most common types of fitting systems used are Cold Expansion Fittings and Metal or Plastic Insert Fittings Other types of fittings are available but are less common 19 21 21 20 Chapter 5 JoInInG METHodS Cold Expansion Fittings with PEX Reinforced Rings This type of fitting requires that the PEX piping with a reinforcing PEX ring placed over the end of the pipe is expanded before the fitting is inserted into the pipe end The expanded pipe end is allowed to retract onto the fitting to form the sealthe memory of the pipe allows it to tighten over the fitting An expander tool is required to expand the pipe and the PEX ring together ASTM F 1960 is applicable to fittings that use a PEX reinforcing ring Figure 51 Cold Expansion Polymer Fitting with PEX Figure 52 Cold Expansion Metal Fitting with PEX Reinforced Ring Reinforced Ring Cold Expansion Fittings with Metal Compression Sleeves This type of fitting requires that the PEX piping is expanded before it is placed over the oversized fitting The pipe shrinks down over the fitting insert then a metal compression sleeve is pulled over the connection compressing the pipe over the fitting A tool is required to expand the pipe and to pull the sleeve over the pipe ASTM F 2080 is applicable to cold expansion fittings that use a metal compression sleeve Figure 53 Cold Expansion Fitting with Metal Compression Sleeve 20 20 20 21 Chapter 5 JoInInG METHodS Metal or Plastic Insert Fittings This type of fitting uses a metal crimp ring that is compressed around the PEX piping to secure it to the fitting The crimp ring can be copper or stainless steel Fittings can be made of copper brass bronze or plastic The fitting will typically have a barbed or ribbed annular end The PEX pipe slides over the barbed or ribbed annular section Prior to making the connection the metal crimp ring is slid over the PEX piping and away from the end of the pipe The piping is pushed over the fitting the crimp ring is slid down over that section and aligned over the fitting ribs and a tool is used to compress the crimp ring around the assembly Copper Crimp Ring The copper ring is crimped equally around the fitting The gonogo gauge ensures a proper crimp Some manufacturers use orings on their metal fittings to make the seal with the pipe ASTM F 1807 is the applicable standard for metal insert fittings ASTM F 2159 is the applicable standard for plastic fittings ASTM 2434 is the applicable standard for metal insert fittings with orings Figure 54 Metal Insert Fitting with Copper Crimp Ring Figure 55 Plastic Insert Fitting with Copper Crimp Figure 56 Metal Insert Fitting with Orings and Ring Copper Crimp Ring 21 23 23 22 Chapter 5 JoInInG METHodS Stainless Steel Clamp The stainless steel ring is crimped using a ratcheting tool which only releases once a proper crimp is achieved ASTM 2098 is the applicable standard for stainless steel insert rings Figure 57 Metal Insert Fitting with Stainless Steel Figure 58 Metal Insert Fitting with Stainless Steel Clamp Band Clamp Sleeve Stainless Steel Sleeve This type of fitting is made of metal and uses a press sleeve or cap to secure the PEX pipe to the fitting These fittings have ribbed annular ends that are inserted into the PEX pipe A sleeve or cap slides over the outer part of the piping and the fitting is inserted into the pipe The pipe must be fully inserted A press tool is used to make the final connection It is important that the appropriate tool is used per manufacturers instructions This type of fitting is often used in other industries to make pneumatic or hydraulic hose line connections Figure 59 Metal Insert Fitting with Stainless Steel Press Sleeve 22 22 22 23 Chapter 5 JoInInG METHodS Push Type Fittings This type of fitting uses an interlocking mechanism to connect the PEX pipe to the fitting The pipe is inserted or pushed into the fitting and locked into place with a fastening device that keeps the pipe from being backedout or disconnected This type of fitting is sometimes referred to as a quick connect fitting Push type fittings typically use some type of oring or gasket to form a seal around the PEX pipe A support liner is inserted into the pipe and a fastening system with a locking component such as a snap ring or twist collar is used to ensure that the connection remains permanent ASSE 1061 and IAPMO IGC 188 are the applicable standards for push type fittings Not all fittings of this type are permitted to be installed in inaccessible locations or underground Verify with your manufacturer and local codes before installation Figure 510 Push Type Fitting 23 25 25 24 Chapter 5 JoInInG METHodS Standard Specifications for Fittings Fittings are categorized in accordance with ASTM or IAPMO specifications as follows ASTM F 1807 Standard Specification for Metal Insert Fittings Utilizing a Copper Crimp Ring for SDR9 CrossLinked Polyethylene PEX Tubing This specification covers metal insert fittings and copper crimp rings for use with PEX tubing that meet requirements in ASTM F 876 and F 877 These fittings are intended for use in 100 psi 690 kPa cold and hotwater distribution systems operating at temperatures up to and including 180ºF 82ºC Requirements for materials workmanship dimensions and markings to be used on fittings and rings are also included Size range is 38 to 1 14 inches ASTM F 1960 Standard Specification for Cold Expansion Fittings with PEX Reinforcing Rings for Use with CrossLinked Polyethylene PEX Tubing This specification covers cold expansion fittings and PEX reinforcing rings for use with PEX plastic tubing that meet requirements of ASTM F 876 and F 877 These fittings are intended for use in 100 psi 690 kPa cold and hotwater distribution systems operating at temperatures up to and including 180ºF 82ºC The system is comprised of a PEX reinforcing ring and a cold expansion fitting Included are requirements for materials workmanship dimensions and markings to be used on fitting components Size range is 38 to 1 12 inches ASTM F 2080 Standard Specification for Cold Expansion Fittings with Metal Compression Sleeves for use with PEX Pipe This specification covers coldexpansion fittings using metal compression sleeves for use with PEX plastic pipe that meet requirements of ASTM F 876 and F 877 whereby the PEX pipe is coldexpanded before fitting assembly These cold expansion fittings and metal compression sleeves are intended for use in residential and commercial hot and cold potable water distribution systems with continuous operation at pressures up to and including 100 psi 690 kPa and at temperatures up to and including 180ºF 82ºC Included in the specification are requirements for materials workmanship dimensions and markings to be used on fittings and compression sleeves Performance requirements are as referenced in ASTM F 877 Size range is 38 to 2 inches ASTM F 2098 Standard Specification for Stainless Steel Clamps for Securing SDR9 CrossLinked Polyethylene PEX Tubing to Metal Insert Fittings This specification covers stainless steel clamps for use with four sizes of insert fittings that comply with F 1807 and crosslinked polyethylene PEX plastic tubing that complies with F 876 or F 877 These clamps are intended as an alternative to the copperalloy crimp rings of Specifications F 1807 or F 2159 for use in 100 psi 6895 kPa cold and hotwater distribution systems operating at temperatures up to and including 180ºF 82ºC Included are requirements for materials workmanship dimensions and marking of the stainless steel clamps requirements for deforming the clamps which apply to assemblies of PEX tubing and Specifications F 1807 and F 2159 insert fittings secured with deformed clamps per this specification 24 24 24 25 Chapter 5 JoInInG METHodS ASTM F 2159 Standard Specification for Plastic Insert Fittings Utilizing a Copper Crimp Ring for SDR9 CrossLinked Polyethylene PEX Tubing This specification covers plastic insert fittings and copper crimp rings for use with PEX pipe that meets requirements in ASTM F 876 and F 877 It establishes requirements for sulfone plastic insert fittings and copper crimp rings for PEX plastic tubing These fittings are intended for use in 100 psi 690 kPa cold and hotwater distribution systems operating at temperatures up to and including 180ºF 82ºC Included are requirements for material molded part properties performance workmanship dimensions and markings to be used on fittings and rings Size range is 38 to 1 inch ASTM F 2434 Standard Specification for Metal Insert Fittings Utilizing a Copper Crimp Ring for SDR9 PEX Tubing and SDR9 PEXALPEX Tubing This specification covers metal insert fittings with oring seals and copper crimp rings for use with crosslinked polyethylene PEX tubing in 12 34 1 and 1 14 inch nominal diameters that meet the requirements for Specifications F 876 and F 877 These fittings are intended for use in 100 psi 6895 kPa cold and hotwater distribution systems operating at temperatures up to and including 180ºF 82ºC Included are the requirements for materials workmanship dimensions performance and markings to be used on the fittings and rings Size range is 12 to 1 12 inches IAPMO IGC 188 Removable and NonRemovable Push Fit Fittings This specification covers removable and nonremovable push fit fittings for use with PEX pipe that meet requirements in ASTM F 876 and F 877 The purpose of this standard is to establish a generally acceptable standard for fittings with a quick assembly pushfit mechanism that are used with various types of outside diameter controlled tubing The fittings range in size from 38 to 2 inches This standard covers minimum requirements for materials of construction and prescribes minimum performance requirements for fitting joints and marking and identification requirements ASSE Standard 1061 This standard applies to pushfit fittings that can be used with one or more of the following materials 1 PEX tubing complying with ASTM F 876 or ASTM F 877 2 Type K L and M copper tubing complying with ASTM B 88 and 3 CPVC tubing complying with ASTM D 2846 Pushfit fittings may be designed to be used with one or more types of tubing that conform to the dimensions as specified in their respective standard This standard serves to supplement ASTM F 877 ASTM D 2846 and ASTM B 88 in describing a test method for a specific type of pushfit fitting system to be used with PEX Copper andor CPVC tubing This standard covers minimum fitting joints marking and identification 25 27 27 26 Chapter 5 JoInInG METHodS 26 26 26 27 6 TYPES oF PEX PLuMBInG SYSTEMS The unique properties of PEX piping allow it to be configured in a number of different residential plumbing system designs This section describes three layout options trunk and branch homerun and remote manifold By carefully choosing the right system for the application the plumbing designer can produce a home that balances cost installation time and performance 27 29 29 28 Chapter 6 TYPES oF PEX PLuMBInG SYSTEMS Trunk and Branch For decades trunk and branch TB piping systems have been used by plumbers for potable water distribution using rigid plastic or metal pipe Installation of PEX piping can be performed in a similar manner using a main trunk line to supply various branch takeoffs to specific outlets Typically the trunk line services numerous outlets while the branch line services generally one to three closely grouped outlets such as in a bathroom Installation of PEX piping in the TB design follows the general design requirements established in plumbing codes As with rigid piping systems use of tee and elbow fittings allows for the connection of branch takeoffs from the main trunk However given the fact that PEX is available in long coils the use of coupling fittings can be reduced or eliminated Unlike rigid pipe systems many elbow fittings can be eliminated in favor of sweep turns of the piping Specific features and advantages of the PEX trunk and branch design include Simple system design conversion from rigid piping to flexible PEX piping Opportunities to reduce the number of fittings installed TB systems will deliver hot water quicker during sequential flows TB systems will generally supply one fixture at a higher pressure Figure 61 PEX Pipes in a Trunk and Branch System Design 28 28 28 29 Chapter 6 TYPES oF PEX PLuMBInG SYSTEMS HomeRun The unique features of PEX piping make it ideal for use in manifoldtype system designs commonly referred to as homerun plumbing systems In this design all fixtures are fed from dedicated piping that runs directly and unbroken from central manifolds The hot water manifold should be located in close proximity to the hot water source to ensure fast and efficient delivery All outlets are individually fed from a common manifold or two central manifolds hot and cold Because inline fittings are eliminated pressure losses along the line are reduced allowing the piping size to be reduced for certain fixtures Threeeighthsinch piping may be used for lower flow applications and 12inch piping is recommended for higher flow applications The homerun system often has more evenly distributed pressure losses when flowing water to fixtures since all lines are fed from a common point rather than adding multiple fixtures into the same pipe section Smaller diameter pipe also results in quicker delivery of hot water from the water heater although each line must be purged independently If the manifold is installed using valved outlets many plumbing codes do not require a second valve at the fixture speeding installation and adding convenience much like an electrical breaker panel Specific features and advantages of the PEX homerun design include Easier piping runs to each fixture using smaller diameter piping Opportunity to eliminate all fittings between the manifold and the outlet Opportunity to have centrally located individual shutoffs housed at the manifold Quicker delivery of hot and cold water to the outlets A more stable pressure to each fixture when operating simultaneous fixtures Figure 62 PEX Pipes in a HomeRun Design 29 31 31 30 Remote Manifold A third method for installing PEX piping combines elements of the first two systems and is typically referred to as a remote manifold system design The basic approach to this system is running hot and cold trunk lines to some convenient location in close proximity to multiple fixtures such as for a bathroom group At this point a smaller remote manifold is installed on each trunk line The remote manifolds can be flowthrough or closed end Individual branch lines are then run to each fixture in the same manner as the central manifold Manifolds with valves must be installed in accessible locations manifolds without valves may be installed in enclosed spaces The remote manifold system performs in a similar manner to the TB system However it simplifies the installation due to the reduced number of fittings that are required Specific features and advantages of the PEX remote manifold design include Relatively simple system design conversion from rigid piping to flexible PEX piping Opportunities to reduce the number of fittings installed Quicker hot water delivery during sequential flows Opportunity to have centrally located individual shutoffs housed at the remote manifold Figure 63 PEX Pipes in a Remote Manifold Design 30 30 30 31 7 dESIGn The unique features of PEX piping allow for a great deal of system design freedom that can increase the performance and savings associated with the plumbing system In todays high performance homes many designers recognize that the plumbing system can be designed to provide hot or cold water faster with much less energy loss PEX plumbing systems can be designed to enhance these features but like any plumbing system PEX piping systems perform best and cost less to install when planned during the homes design phase Advanced planning allows maximum performance while limiting the lengths of pipe and number of fittings used And when considered early enough in the house planning stage a few simple room layout considerations can greatly improve the performance of the plumbing system By consulting the codes and local inspectors in advance builders and plumbers can also avoid costly time delays due to code issues arising during construction This chapter describes a process that provides the guidance and tools needed to successfully layout a PEX piping system in nearly any home Four major areas of the design process are highlighted Consult Local Codes Optimize Home Layout Select Piping System Type Plan Piping Routing Manifold and Valve Locations Consult Local Codes If PEX piping has not been used before or is still uncommon in your local area it is helpful to review the local codes for use of PEX piping As discussed in the Chapter 4 of this document PEX piping is approved for use in all model codes Local amendments may restrict or change 31 33 33 32 Chapter 7 dESIGn the way PEX may be used for certain applications For that reason it is important to consult local codes to determine specific requirements before beginning a new piping design It may also be helpful to consult with local building inspectors to notify them in advance that you plan to use PEX piping for your project They can be helpful in pointing out local requirements and amendments Alerting the inspector of your intent to use a new technology in advance can help to avoid delays that often occur when an unfamiliar material is encountered on the jobsite This design manual may be useful as a reference guide for an inspector who is unfamiliar with PEX In the event that questions arise regarding the application performance or code acceptance of PEX both the Plastics Pipe Institute PPI and the Plastic Pipe and Fittings Association PPFA can provide support Each organization can provide technical and training materials to aid code officials and plumbers Optimize Home Designs Ironically some of the most substantial problems with modern plumbing system designs relate not to the piping itself but to the design and layout of the house The materials that are chosen for framing the location of rooms the location of the water heaters and the point at which the water main enters the home all have a substantial impact on the performance of a plumbing system Often the design of the plumbing system is left until the end of the design process when the home layout is largely determined This often results in a poorly performing and excessively costly system By observing a number of guidelines early in the home design process PEX piping can be installed in a way that minimizes costs eases installation and increases homeowner satisfaction The key to optimizing home designs for PEX plumbing is to minimize pipe lengths from the water main and water heater While this may seem intuitive it cannot be stressed enough Short piping runs result in shorter wait times for hot water fewer fittings faster installation time and lower material costs This can be accomplished by the builder or designer in the early planning stage using several basic design principles 1 Group fixtures together Grouping plumbing fixtures around a common location can result in saving time materials hot water energy and water This can be done between floors as well such as in the case of stacked bathrooms Where possible avoid locating bathrooms long distances from the water heater 2 Centrally locate distribution point Centrally located water heaters and incoming water supplies can significantly improve the performance of a plumbing system Often water heaters are arbitrarily located for convenience or placed in the utility room as far from the living space as possible This approach often leads to exceedingly long plumbing runs along with the resultant increase in materials installation time and water and energy use Whenever feasible locate the water main and heater as close as possible to the midpoint of the fixture groupings to keep piping runs short 3 Create spaces for bundled pipe runs Particularly applicable to homerun PEX plumbing runs where few fittings are installed simultaneous installation of multiple piping runs will reduce installation time The flexibility of PEX piping and the long unbroken lengths that can be easily spooled enable the simultaneous installation of multiple plumbing lines 32 32 32 33 Chapter 7 dESIGn running in the same direction using common holes and chases By creating space in soffits and chases for piping bundles installation time can be reduced However cold and hot water lines should be bundled separately 4 Use building elements that ease piping installation Using building elements such as open web floor trusses in some locations can dramatically speed up the process of installing plumbing piping This can also speed up the process of installation of other mechanicals including ducting and wiring Select Piping System Design The next step for the designer plumber and builder is to select the most appropriate plumbing system design for the home The unique properties of PEX piping allow it to be configured in a number of different designs All have been shown to work well in residential applications and all are code approved Depending on the design of the home each has different performance characteristics installation costs material costs and ease of installation The selection of a system design is generally based on a combination of key factors such as material cost labor time ease of installation system performance and installer preference The challenge for a plumbing designer is to select the system that balances the unique needs of the installer homeowner and builder The purpose of this chapter is to provide a comparison of the three most prevalent PEX plumbing systems trunk and branch homerun and remote manifold and the guidance to select between system types Selecting among the three systems described is not cut and dry and often involves a balance of the key factors since each project installer and circumstance is different Fortunately there is no wrong choice All three system designs will supply sufficient flow and pressure to the outlets even when the base riser pressure is 40 psi and the length to the farthest outlet is 100 feet But the costs and performance of each system do vary for each house design Selecting the best system for your project can reduce installation costs minimize installation headaches and lead to more satisfied homeowners To aid in the decisionmaking process several tools are provided 1 General Rankings of the Systems for Key Factors This general comparison will provide a place to start and compare how the systems stack up based on your priorities 2 Example Layouts Detailed layouts of each system are provided for four common house types By selecting the type that most closely resembles your project you can see how the systems compare for your building design 3 Performance Testing The three systems were compared and tested in comprehensive laboratory tests By examining the test data you can identify differences in the systems performance in varying scenarios 4 Industry Technical Support Manufacturers and organizations offer a range of resources to assist PEX users The support ranges from general information to technical assistance on specific projects 33 35 35 Chapter 7 dESIGn 34 Chapter 7 dESIGn General Rankings of the Systems for Key Factors The general characteristics of the systems are ranked in Table 71 Given the wide difference between housing designs and preferences they may not apply in every situation but are useful for general guidance as you design your home The best way to use the table below is to establish the relative priority of key factors and use the rankings of system designs to provide a starting point for the system to be selected For example if when considering the factors in the table below you determine that your top three factors are 1 Minimizing Fittings and Joints5 2 Centralized Shutoff Valving 3 Pressure Stability with Use of Multiple Fixtures Then given the fact that the homerun system ranks at the top of all three it is a logical place to start However if your top factors give you three different best designs the right choice is not as obvious You will then need to consider other factors and further explore the detailed design of your home to make a choice The example layouts later in this chapter may then be helpful in making a choice Table 71 General Rankings of the System Characteristics Factor Minimize Pipe Used Trunk and Branch Remote Manifold HomeRun Minimize Fittings and Joints HomeRun Remote Manifold Trunk and Branch Sequential Flow Hot Water Delivery Time Trunk and Branch Remote Manifold HomeRun Minimize Hot Water Wait Time HomeRun Remote Manifold Trunk and Branch Single Fixture Pressure Trunk and Branch HomeRun Remote Manifold Pressure Stability with Use of Multiple Fixtures HomeRun Remote Manifold Trunk and Branch Centralize Shutoff Valving HomeRun Remote Manifold Trunk and Branch Joint Accessibility During Installation HomeRun Remote Manifold Trunk and Branch Indicates the highest level of performance for that factor Indicates typical performance 5 A fitting is the device that allows the PEX pipe to change direction or size ie tees elbows reducers A joint is the connection of the PEX pipe to a fitting ie a tee fitting has three joints 34 34 34 Chapter 7 dESIGn 35 Chapter 7 dESIGn Cost has been omitted as a factor in this guide Since local labor costs vary and there is variation between the fitting and piping costs offered by different manufacturers this guide simply provides information on the amount of pipe and fittings needed Since the balance between material and labor cost varies across the country the determination of actual cost estimates and total cost comparison between system designs is left to the designer or installer Example Layouts The following plumbing system layouts provide supply water diagrams and estimated fittings and piping descriptions for the four most common house types Colonial Ranch Townhouse and Condominium Each house type has three piping layouts that illustrate each of the three system designs Piping lengths and fitting and joint counts are provided for each system to provide a comparison of material use and labor required You can select the home design that most closely resembles your home design to help select the system that is right for you Note that in these designs few obstructions are accounted for and thus represent idealized pipe runs with a minimum of fittings Table 72 outlines the number and type of fixtures for each house Table 72 Fixture Count for each House Type Fixture Colonial Ranch Townhouse Condominium Kitchen Sink 1 1 1 1 Dishwasher 1 1 1 1 Lavatory 4 3 2 3 Water Closet 3 2 2 2 ShowerTub 3 3 1 3 Clothes Washer 1 1 1 1 Utility Sink 1 0 0 0 Hose Bibbs 2 2 2 0 Total 16 13 10 11 35 37 37 Chapter 7 dESIGn 36 Chapter 7 dESIGn Colonial Layout The Colonial house layout has approximately 2000 square feet of floor area The water main enters the house under the unfinished basement slab The water heater is located near the main water line in the basement The first floor has a living room dining room kitchen family room and a powder room The second floor has four bedrooms two full baths and the clothes washer Table 73 Fixture Summary for the Colonial House Level Kitchen Sink Dishwasher Lavatory Water Closet ShowerTub Clothes Washer Utility Sink Hose Bibb Total Basement 0 0 0 0 0 0 1 0 1 First Floor 1 1 1 1 0 0 0 2 6 Second Floor 0 0 3 2 3 1 0 0 9 Total 1 1 4 3 3 1 1 2 16 Table 74 Material Summary for the Colonial House System Length of Cold Pipe Length of Hot Pipe Fittings Manifolds Joints 1 34 12 1 34 12 Tees Elbows Main Remote Fixtures Piping Trunk and Branch 27 80 110 0 80 98 25 10 0 0 26 97 Home Run 33 12 602 0 12 428 2 7 2 0 26 49 Remote Manifold 27 93 152 0 93 107 8 13 0 7 26 83 In larger homes with a large separation between bathrooms the trunk and branch design uses the least amount of total pipe but the most fittings and joints The homerun system uses the most piping 24 times on average and the least amount of fittings and joints While the home run system uses more piping the piping has a smaller diameter which is easier to handle and install particularly around bends An appropriate balance between labor and material costs as well as the relative performance of the systems is important when deciding on a system layout for your particular house 36 36 36 Chapter 7 dESIGn 37 Chapter 7 dESIGn Figure 71 Trunk and Branch Isometric Riser for the Colonial House Figure 72 HomeRun Isometric Riser for the Colonial House 37 39 39 Chapter 7 dESIGn 38 Chapter 7 dESIGn Figure 73 Remote Manifold Isometric Riser for the Colonial House 38 38 38 Chapter 7 dESIGn 39 Chapter 7 dESIGn Ranch Layout The Ranch house has approximately 1300 square feet of onestory floor area The water main enters the house under the slab on grade The onestory floor plan includes a great room a kitchen a dining room three bedrooms and two full baths The water heater and clothes washer are located in the utility room Table 75 Fixture Summary for the Ranch House Level Kitchen Sink Dishwasher Lavatory Water Closet ShowerTub Clothes Washer Utility Sink Hose Bibb Total Main Floor 1 1 3 2 3 1 0 2 13 Table 76 Material Summary for the Ranch House System Length of Cold Pipe Length of Hot Pipe Fittings Manifolds Joints 1 34 12 1 34 12 Tees Elbows Main Remote Fixtures Piping Trunk and Branch 25 75 112 0 72 81 20 5 0 0 21 71 Home Run 25 10 413 0 10 294 2 5 2 0 21 39 Remote Manifold 25 59 196 0 59 159 8 4 0 4 21 53 In home layouts with a large separation between fixtures the trunk and branch design uses the least amount of pipe followed by the remote manifold design The homerun system uses the most piping 18 times more on average and the least amount of fittings and joints The home run system uses more piping but with smaller diameters which is easier to handle and install particularly around bends An appropriate balance between labor and material costs as well as the relative performance of the systems is important when deciding on a system layout for your particular house 39 41 41 Chapter 7 dESIGn 40 Chapter 7 dESIGn Figure 74 Trunk and Branch Isometric Riser for the Ranch House Figure 75 HomeRun Isometric Riser for the Ranch House 40 40 40 Chapter 7 dESIGn 41 Chapter 7 dESIGn Figure 76 Remote Manifold Isometric Riser for the Ranch House 41 43 43 Chapter 7 dESIGn 42 Chapter 7 dESIGn Townhouse Layout The Townhouse has two stories and is approximately 1000 square feet of floor area The water main enters the house under the first floors slab on grade The first floor has a living room kitchen dining room and a powder room The second floor has two bedrooms and one full bath The water heater and clothes washer are located on the first floor Table 77 Fixture Summary for the Townhouse Level Kitchen Sink Dishwasher Lavatory Water Closet ShowerTub Clothes Washer Utility Sink Hose Bibb Total First Floor 1 1 1 1 0 1 0 2 7 Second Floor 0 0 1 1 1 0 0 0 3 Total 1 1 2 2 1 1 0 2 10 Table 78 Material Summary for the Townhouse System Length of Cold Pipe Length of Hot Pipe Fittings Manifolds Joints 1 34 12 1 34 12 Tees Elbows Main Remote Fixtures Piping Trunk and Branch 0 66 86 0 30 44 14 8 0 0 15 59 Home Run 0 42 247 0 11 138 2 8 2 0 15 39 Remote Manifold 0 67 100 0 30 44 5 7 0 2 15 42 In this more compact house design the differences between the trunk and branch and remote manifold systems are primarily in reduced fittings and joints for the remote manifold system The homerun system uses considerably more pipe 19 times more on average as the trunk and branch and remote manifold designs The homerun system uses more piping with smaller diameters which is easier to handle and install particularly around bends An appropriate balance between labor and material costs as well as the relative performance of the systems is important when deciding on a system layout for your particular house 42 42 42 Chapter 7 dESIGn 43 Chapter 7 dESIGn Figure 77 Trunk and Branch Isometric Riser for the Townhouse Figure 78 HomeRun Isometric Riser for the Townhouse 43 45 45 Chapter 7 dESIGn 44 Chapter 7 dESIGn Figure 79 Remote Manifold Isometric Riser for the Townhouse 44 44 44 Chapter 7 dESIGn 45 Chapter 7 dESIGn Condominium Layout The Condominium has approximately 1200 square feet of floor area It has a living room kitchen dining room two bedrooms and two full baths The clothes washer is located in the unit The condominium building has a central plant for water heating therefore there is no water heater located in the unit Table 79 Fixture Summary for the Condominium Level Kitchen Sink Dishwasher Lavatory Water Closet ShowerTub Clothes Washer Utility Sink Hose Bibb Total Main Floor 1 1 3 2 3 1 0 0 11 Table 710 Material Summary for the Condominium System Length of Cold Pipe Length of Hot Pipe Fittings Manifolds Joints 1 34 12 1 34 12 Tees Elbows Main Remote Fixtures Piping Trunk and Branch 0 45 120 0 45 104 17 0 0 0 19 53 Home Run 0 10 295 0 10 242 1 2 2 0 19 29 Remote Manifold 0 35 132 0 35 115 5 0 0 4 19 37 The trunk and branch system uses the most tees which increases the number of joints The trunk and branch and remote manifold system layouts are similar in pipe use but the remote manifold uses fewer fittings resulting in fewer joints The homerun system uses the most pipe 18 times more on average and the least amount of fittings The homerun system uses more pipe with smaller diameters which is easier to handle and install particularly around bends An appropriate balance between labor and material costs as well as the relative performance of the systems is important when deciding on a system layout for your particular house 45 47 47 Chapter 7 dESIGn 46 Chapter 7 dESIGn Figure 710 Trunk and Branch Isometric Riser for the Condominium Figure 711 HomeRun Isometric Riser for the Condominium 46 46 46 Chapter 7 dESIGn 47 Chapter 7 dESIGn Figure 712 Remote Manifold Isometric Riser for the Condominium 47 49 49 Chapter 7 dESIGn 48 Chapter 7 dESIGn Performance Verification Laboratory Testing A set of laboratory tests using typical plumbing fixtures and plumbing pipe sizes runs and fittings was performed to demonstrate the flow characteristics of the three different PEX systems Results of this testing indicate that all three systems will supply adequate pressure and water delivery to a remote shower fixture located 100 feet from the base riser with an elevation head of 15 feet Base source pressures of 40 60 and 80 psi were used in each of the different system designs Multiple tests were performed to add simultaneous flows from other fixtures including a shower lavatory kitchen and water closet Test results are shown in Chapter 8 Industry Technical Support If you have questions that have not been answered in this Design Guide you can contact the PEX manufacturer directly The following websites provide a wealth of general information on PEX piping Plastics Pipe Institute wwwplasticpipeorg Plastic Pipe and Fittings Association wwwppfahomeorg ToolBaseorg wwwtoolbaseorg Manufacturers of PEX piping and fittings can also provide specific technical assistance during the design planning and installation phases Contact information for each can be found at the PPI and PPFA and websites and on the individual manufacturers sites Plan Pipe Routing Manifold and Valve Locations Once the system design is selected the final step in the design process is to plan pipe routing manifold and valve locations As in the case of the home design optimization there are several guidelines that can simplify this process Bear in mind that PEX piping is available in continuous coils as well as 20foot straight lengths Consult the local codes for specific installation requirements for your project Guidelines for optimizing the design of a PEX plumbing system include 1 Minimize fittings The flexibility of PEX piping enables it to be easily installed around obstructions and through framing members Use of sweep turns ie bending the pipe in a gentle sweep rather than using solid fittings to change direction can result in quicker installations fewer mechanical fittings and less resistance due to pressure drops common through fittings 2 Group fixtures together If using trunk and branch or remote manifold use common trunk lines to feed multiple fixture groups For example if two bathrooms are stacked use a single remote manifold to feed both rather than two remote manifolds 48 48 48 Chapter 7 dESIGn 49 Chapter 7 dESIGn 3 Minimize pipe lengths Though this may seem intuitive attention to this detail should lead to efficiently installed plumbing systems especially when considering plumbing layouts using PEX piping 4 Select appropriate pipe diameter Many plumbing systems are installed using standard practices that apply to very large homes but are excessive for smaller homes Taking a short amount of time to plan the piping sizes needed to supply the proper flow rates at the required pressure will result in the use of pipe sizes that deliver the required fixture flow rate but are not oversized Oversized plumbing system designs result in wasted energy and water as well as reduce customer satisfaction with the plumbing system 5 Bundle pipe runs Applicable particularly to PEX plumbing runs where few fittings are installed installation of multiple piping runs at the same time will reduce installation time The flexibility of PEX piping and the long unbroken lengths that can be easily spooled to enable the simultaneous installation of multiple plumbing lines running in the same direction using common holes through barriers such as joists 6 Plan for solid attachment of transition points The flexibility of PEX piping also requires that the transition to threaded fittings or rigid piping be performed correctly As with most piping materials solid connection points and solid attachment points are necessary when threading on valves and transition fittings to other materials 7 Use color coding PEX is available in different colors Using dedicated colors for hot cold and greywater where applicable can be helpful for installers homeowners and future retrofits Before locating manifolds determine whether valves will be placed at fixtures or on manifolds Some jurisdictions require valves at the fixture while others allow them to be located on central manifolds In some cases the homeowner may express a preference for the location of shutoff valves If valves are to be placed on manifolds they must be situated to allow easy access This can be accomplished by placing them behind access panels or open in basements laundry rooms mechanical rooms or garages where no freeze potential exists It is also important to label each valve on the manifold to ensure easy identification of the distribution lines If valves are not placed on the manifolds and local codes allow the manifolds may be enclosed within walls or floors similar to any other fitting such as a tee or ell 49 50 50 51 8 PErForMAnCE dATA System Performance Comparison Each of the three PEX plumbing configurations described in this guide can be installed in most homes with satisfactory performance The different systems offer opportunities to optimize the performance of the plumbing system reduce the installed cost and increase overall customer satisfaction and acceptance In order to quantify the differences between PEX system designs each system was tested in the laboratory to provide a similar set of conditions under which the systems are installed and operated Actual residential plumbing fixtures piping layouts with fittings and even elevation changes were installed and operated This provided a consistent comparison between system designs as well as an indication of the minimum performance characteristics of each system PEX piping was installed in each of the three configurationstrunk and branch homerun and remote manifoldwith overall results showing All systems had similar flow characteristics at each of the fixtures when flowing independently All system designs responded in a similar manner to simultaneous flow events more than one fixture flowing at once Minor differences in the actual measured flow and pressure at a test fixture emerged when simultaneous flow events occurred Test System Design and Setup A set of plumbing fixtures were installed in a laboratory setting to provide actual flow and pressure data during operation of the fixtures These data provide assurance that the PEX plumbing system design is capable of supplying the required flow rates during operation of the fixture In addition the test results provide assurance that the plumbing system design will 51 53 53 Chapter 8 PErForMAnCE dATA 52 Chapter 8 PErForMAnCE dATA supply adequate flow and pressure to a remote test fixture while other fixtures are operated simultaneously The test system was constructed and reconfigured for each type of PEX plumbing design including the standard trunk and branch TB the homerun HR and the remote manifold RM A primary Test Fixture TF represented by a tubshower unit was installed and instrumented to measure flow rate and flow pressure on the hot and cold lines as well as mixed water temperature Figure 81 shows the laboratory system diagram for the TB system Other test system designs are shown in Appendix A The TF was located the farthest from the source of all the fixtures and was operated in shower mode during all tests The operating performance of this test fixture represents the worst case characteristics of the full system since all other fixtures were closer to the source Figure 82 shows the laboratory setup configured with the fixtures and the TB system design with 100foot distance to the TF Figure 83 shows the TF with the sensors for pressure and flow installed Figure 81 Fixture Layout for Laboratory Testing 52 52 52 Chapter 8 PErForMAnCE dATA 53 Chapter 8 PErForMAnCE dATA Figure 82 Laboratory Test Setup with Five Outlets Hot Water Tank and TB System Figure 83 The Test Fixture Shower with Flow and Pressure Sensors Installed 53 55 55 Chapter 8 PErForMAnCE dATA 54 Chapter 8 PErForMAnCE dATA Table 81 shows the set of plumbing fixtures installed to represent specific residential outlets These fixtures were connected to the three different PEX plumbing configurations Tests included using two different total distances of pipe run to the farthest TF 100 feet and 60 feet The piping runs to the other fixtures were run in lengths that matched the type of piping system installed ie if the HR system was being tested all fixtures are plumbed with the HR system Table 81 Plumbing Fixtures Installed in the Test Plumbing System Fixture Length from Source feet Elevation Above Source Operation During Test TubShower TF 60 or 100 15 FullOn Shower Lavatory 60 or 100 15 Intermittent Water Closet tank type 55 or 95 15 Intermittent Kitchen Faucet Less than 40 5 Intermittent TubShower 2 Less than 40 6 Intermittent Diagrams of all the test piping arrangements are shown in Appendix A Two sets of tests were performed for each plumbing system One test recorded pressure and flow data at the TF while other fixtures were operated A second set of tests was performed to measure the length of time it took for hot water to reach the TF The test was started after the piping was stabilized to the incoming water temperature Plumbing System Pressure and Flow Test Results For all pressure and flow tests the farthest shower fixture TF was operated in the shower fullon mode The flow pressure and flow rates for each of the hot and cold water supplies to the TF were recorded During the operation of the TF other simultaneous flows were added as described in Table 82 For this the TF flow and pressure data were recorded as well as the total hot and cold water supply to the other fixtures and the pressure at the base of the riser Table 82 Pressure and Flow Test Regime Test No Fixtures Operated Nomenclature 1 Test Fixture TF TF 2 TF and Lavatory TFLav 3 TF and Water Closet TFWC 4 TF and Kitchen Faucet midposition TFKit 5 TF and 2nd Shower fullon TFSh2 6 No 5 and Kitchen TFSh2Kit 7 No 6 and Lavatory TFSh2KitLav 8 No 7 and Water Closet TFSh2KitLavWC 54 54 54 Chapter 8 PErForMAnCE dATA 55 Chapter 8 PErForMAnCE dATA Flow and pressure measurements were recorded for each of the tests and are recorded in Table 83 Each system was tested at three different static pressures measured at the base of the riser 40 60 and 80 psi Table 83 shows the results of the TF flowing with no simultaneous fixtures operating Table 83 TF Flow and Pressure Data for Each System System Type Distance to TF Riser Pressure Riser Pressure TF Hot Valve Flow TF Hot Valve Pressure TF Cold Valve Flow TF Cold Valve Pressure psi gpm psi gpm psi TB 100 40 psi 400 17 316 02 351 RM 100 40 psi 400 17 316 02 350 HR 100 40 psi 400 17 293 02 350 TB 100 60 psi 600 22 500 03 552 RM 100 60 psi 600 22 497 03 549 HR 100 60 psi 600 21 464 03 548 TB 100 80 psi 800 26 687 03 751 RM 100 80 psi 800 26 687 03 751 HR 100 80 psi 800 25 636 03 750 TB 60 40 psi 400 18 320 02 351 RM 60 40 psi 400 18 321 02 350 HR 60 40 psi 400 17 308 02 350 TB 60 60 psi 600 22 508 03 549 RM 60 60 psi 600 22 506 03 550 HR 60 60 psi 600 22 488 03 549 TB 60 80 psi 800 26 699 03 752 RM 60 80 psi 800 26 702 03 751 HR 60 80 psi 800 25 669 03 751 Note 1 TB Trunk and Branch RM Remote Manifold HR Homerun Note 2 Systems installed at either 100 or 60 to TF Note 3 Nominal Pressures of 40 60 and 80 psi are static pressures 55 57 57 Chapter 8 PErForMAnCE dATA 56 Chapter 8 PErForMAnCE dATA The performance data for each of the three system designs shows very similar performance for both the 100foot distance to the TF and the 60foot distance to the TF At 100 feet from the source the TF flow rate on the hot side of the valve was the primary flow and was 15 gpm at a low pressure of 40 psi static The flow rate at the valve increased to 24 gpm for the 60foot distance with a riser pressure of 80 psi static Once the baseline flow performance was verified for the TF additional tests were performed adding simultaneous flows in conjunction with the TF flowing The performance measure of the system capability to supply the farthest fixture is the flow and pressure data at the TF Table 84 shows the performance data for the 100foot tests with a source pressure of 40 psi Table 84 Simultaneous Flow Performance Data 100 Maximum Length 40 psi Source Pressure Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pressure Cold Flow Cold Pressure gpm gpm gpm psi gpm psi gpm psi Trunk and Branch 100 00 00 00 400 00 340 00 352 40 psi Static TF 21 05 16 400 17 316 02 351 TFLav 35 16 19 400 17 312 02 342 TFWC 55 39 16 400 17 319 02 295 TFKit 35 13 22 400 17 313 02 350 TFSh2 42 13 29 400 17 306 02 349 TFSh2Kit 56 22 34 400 17 303 02 347 TFSh2KitLav 70 35 35 400 17 301 02 334 TFSh2KitLavWC 102 59 43 400 17 286 02 293 Remote Manifold 100 00 00 00 400 00 339 00 352 40 psi Static TF 21 04 17 400 17 316 02 350 TFLav 35 14 21 400 17 311 02 346 TFWC 55 39 16 400 18 320 02 318 TFKit 35 13 22 400 17 313 02 349 TFSh2 42 15 27 400 17 306 02 349 56 56 56 Chapter 8 PErForMAnCE dATA 57 Chapter 8 PErForMAnCE dATA Table 84 Simultaneous Flow Performance Data 100 Maximum Length 40 psi Source Pressure continued Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pressure Cold Flow Cold Pressure gpm gpm gpm psi gpm psi gpm psi TFSh2Kit 56 24 32 400 17 305 02 347 TFSh2KitLav 70 36 34 400 17 300 02 340 TFSh2KitLavWC 102 62 40 400 17 298 02 308 HomeRun 100 40 psi Static 00 00 00 400 00 340 00 352 TF 21 04 17 400 17 293 02 350 TFLav 35 12 23 400 17 292 02 350 TFWC 55 37 18 400 17 294 02 350 TFKit 35 12 23 400 17 290 02 350 TFSh2 42 15 28 400 17 286 02 350 TFSh2Kit 56 23 33 400 17 286 02 349 TFSh2KitLav 70 33 37 400 17 284 02 348 TFSh2KitLavWC 102 63 39 400 17 287 02 346 TF Test Shower Fixture 15 elevation Lav Lavatory both valves open 15 elevation WC Water Closet tank type 15 elevation Kit Kitchen midposition 4 elevation Sh2 2nd Shower full open valve 5 elevation Based on the simultaneous flow performance data all systems continued to supply adequate pressure and flow to the remote TF located 100 feet from the source With the source pressure of 40 psi the maximum system flow rate was 80 gpm 50 gpm to the cold supply fixtures and 30 gpm to the hot supply fixtures Table 85 shows similar results with a system design of 60 feet to the TF 57 59 59 Chapter 8 PErForMAnCE dATA 58 Chapter 8 PErForMAnCE dATA Table 85 Simultaneous Flow Performance Data 60 Maximum Length 40 psi Source Pressure Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pressure Cold Flow Cold Pressure gpm gpm gpm psi gpm psi gpm psi Trunk and Branch 60 40 psi Static 00 00 00 400 00 341 00 352 TF 21 04 17 400 18 320 02 351 TFLav 35 14 21 400 17 316 02 345 TFWC 55 39 17 400 18 321 02 312 TFKit 35 13 22 400 17 317 02 350 TFSh2 42 14 28 400 17 309 02 349 TFSh2Kit 56 22 34 400 17 305 02 347 TFSh2KitLav 70 29 35 400 17 304 02 337 TFSh2KitLavWC 102 60 42 400 17 292 02 300 Remote Manifold 60 40 psi Static 00 00 00 400 00 340 00 352 TF 21 03 17 400 18 321 02 350 TFLav 35 13 22 400 17 317 02 348 TFWC 55 39 16 400 18 323 02 331 TFKit 35 11 24 400 17 317 02 350 TFSh2 42 14 28 400 17 311 02 349 TFSh2Kit 56 23 33 400 17 307 02 348 TFSh2KitLav 70 34 36 400 17 304 02 343 TFSh2KitLavWC 102 62 40 400 17 304 02 320 HomeRun 60 40 psi Static 00 00 00 400 00 340 00 351 TF 21 04 17 400 17 308 02 350 TFLav 35 12 23 400 17 307 02 349 TFWC 55 39 16 400 17 316 02 348 TFKit 35 14 22 400 17 306 02 349 TFSh2 42 14 28 400 17 302 02 349 58 58 58 Chapter 8 PErForMAnCE dATA 59 Chapter 8 PErForMAnCE dATA Table 85 Simultaneous Flow Performance Data 60 Maximum Length 40 psi Source Pressure continued Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pressure Cold Flow Cold Pressure gpm gpm gpm psi gpm psi gpm psi TFSh2Kit 56 23 33 400 17 300 02 348 TFSh2KitLav 70 33 37 400 17 298 02 348 TFSh2KitLavWC 102 65 37 400 17 303 02 345 TF Test Shower Fixture 15 elevation Lav Lavatory both valves open 15 elevation WC Water Closet tank type 15 elevation Kit Kitchen midposition 4 elevation Sh2 2nd Shower full open valve 5 elevation The system performance with simultaneous flows was very similar to the previous 100 foot test but with slightly lower pressure drops A static pressure of 40 psi is considered to be a minimum supply pressure A summary of the results for the simultaneous flow system performance at 60 and 80 psi source static pressure is shown in Appendix A Comparing the flow pressure and flow rate is a good way to determine the performance of a plumbing system The limitation is that the pressure at the base of the riser is dependent on the size of the service line meter and water utility supply pressure In order to describe and compare the performance of each type of system the pressure drop from the base of the riser to the farthest outlet including elevation losses can be evaluated Figures 84 and 85 show the comparison of pressure drop based on various outlets in the system flowing with the resultant pressure drop at the farthest fixture Both figures indicate that the homerun system while having a higher pressure drop to the TF has a more consistent pressure drop during simultaneous flow The other systems based on the trunk line feeding branch lines continued to show increasing pressure drop as more fixtures were added to the system In fact when the full set of fixtures was operating simultaneously the trunk and branch system pressure drop exceeded that of the homerun and the remote manifold configurations The remote manifold system is highly dependent on the system design ie the location of the manifolds and the number of fixtures connected to the manifold 59 61 61 Chapter 8 PErForMAnCE dATA 60 Chapter 8 PErForMAnCE dATA Figure 84 Pressure Drop Comparison 100 Distance to TF Figure 85 Pressure Drop Comparison 60 Distance to TF 60 60 60 Chapter 8 PErForMAnCE dATA 61 Chapter 8 PErForMAnCE dATA Wait Time for Hot Water A significant benefit of PEX piping systems is the opportunity to reduce water and energy waste by reducing the amount of time to deliver hot water to the outlet from the water heater Though hard to quantify definitely there are indications that hundreds of gallons of water per year are wasted while waiting for hot water to reach the outlet Tests were also performed on each of the three PEX system designs to compare the time it takes for hot water to be delivered to the test fixture TF Figure 86 shows the results of delivering hot water to the shower fixture after the pipes were flushed with cold city water The results were normalized to keep the flow rates and temperature from the hot water tank constant for all systems Figure 86 Comparison of Hot Water Delivery Time Water and time savings of between 30 percent and 40 percent were identified based on this analysis of the homerun system over either the trunk and branch or remote manifold system designs 61 63 63 62 Chapter 8 PErForMAnCE dATA Test Summary A summary of the performance characteristics of each system is shown in Table 86 The data indicates Trunk and branch and remote manifold systems will supply one fixture at a higher pressure Homerun systems will supply a more stable pressure to each fixture when operating simultaneous fixtures Homerun systems will deliver hot water to the outlet quicker especially when the pipes are at room temperature Trunk and branch and remote manifold systems will deliver hot water quicker during sequential flows All three system designs will supply sufficient flow and pressure to the outlets even when the base riser pressure is 40 psi and the length to the farthest outlet is 100 feet Table 86 Performance Summary 100 Maximum Distance Test Fixture Test Fixture With Test Fixture System Only Simultaneous Only Flow Rate Hot Pressure Hot Flow Rate Hot Pressure Hot Time to 100F Hot Water Time to 110F Hot Water gpm psi gpm psi sec sec 40 psi Static TB 100 17 316 17 286 RM 100 17 316 17 298 HR 100 17 293 17 287 60 psi Static from 53F TB 100 22 500 21 444 719 909 RM 100 22 497 21 463 716 893 HR 100 21 464 21 456 463 568 80 psi Static TB 100 26 687 24 616 RM 100 26 687 25 630 HR 100 26 636 24 620 62 62 62 63 9 InSTALLATIon CrossLinked Polyethylene PEX Hot and ColdWater distribution Systems This chapter is extracted in its entirety from the Plastic Pipe and Fittings Association PPFA document entitled CrossLinked Polyethylene PEX Hot and ColdWater Distribution Systems released in 2006 and is included with permission from the PPFA It is provided as a general reference to supply basic information regarding the installation process for PEX piping in residential water service applications It should not be used in place of the specific manufacturers instructions for the installation of any particular system Local codes provisions may vary and should be consulted before beginning any piping installation Important Notice The information in this manual was gathered from publicly available sources including reports of tests conducted by various independent entities under the test conditions specified in the standards listed The contents of this manual are informational only and are not intended as an endorsement or warranty with respect to any product or system The Plastic Pipe and Fittings Association PPFA and its members have no responsibility for the design administration results or evaluation of any test PPFA and its members make no warranties express or implied as to the fitness of any product or system for any particular purpose the suitability of any product or system for any specific application or the performance of any product or system in actual construction Copyright 2006 Plastic Pipe and Fittings Association 63 65 65 64 Chapter 9 InSTALLATIon l ll i i i l li le pl i ildi isi ll i li i i i iti l l i l i i i i i i No product or system shou d be used or insta ed w thout first rev ew ng a l app cab umb ng or bu ng code prov ons and the manufacturers insta at on or app cat on nstruct ons Local code author es and the product or system manufacturer shou d be consu ted w th respect to unreso ved quest ons or uncerta nt es In the event there is any confl ct or incons stency between the content of th s manual and the applicable building or plumbing code and the manufacturers installation or application instructions the codes and the instructions shall be followed Revision Policy The PPFA Flexible Polyolefin Hot and Cold Water Systems Product Line Committee is responsible for revision of the manual All suggestions and recommendations for revisions shall be addressed to the Committee which shall respond to them as promptly as reasonably possible The Committee shall review the manual in its entirety at least once every three 3 years Published by the Plastic Pipe and Fittings Association 800 Roosevelt Road Building C Suite 312 Glen Ellyn IL 60137 wwwppfahomeorg Copyright 2006 Plastic Pipe and Fittings Association 64 Copyright 2006 Plastic Pipe and Fittings Association 64 64 65 Chapter 9 InSTALLATIon Manual Content Use This manual contains information on the installation of Crosslinked Polyethylene PEX tubing for hot and coldwater distribution systems in residential and light commercial installations using tubing up to 1 inch diameter Information in this manual shall not be separated as it is often interrelated Consult local codes for additional installation requirements For additional information contact Local officials having jurisdiction for codes Manufacturer for specific product information PPFA for general installation instructions Plastics Pipe Institute PPI Other Uses of CrossLinked Polyethylene PEX Tubing Hydronic Radiant Heating Heat Pump Applications Other Uses with Similar Service Requirements Consult tubing manufacturer for details 65 Copyright 2006 Plastic Pipe and Fittings Association 67 67 66 Chapter 9 InSTALLATIon i i i i Tubing Identification Check the PEX tub ng for the proper ASTM ident ficat on mark ng Use ASTM Standard Canadian Standard HotCold Water F 876 or F 876 F 877 and CSA B1375 Standard for Fittings Check for potable water listing NSF International NSFpw or other recognized listing agency Marking Typical Example Tube size ASTM Standard Standard dimension ratio Pressure rating ¾ CTS 0875 OD ASTM F 876 or F 876F 877 SDR 9 160 psi 734F 100 psi 180 F Marks of listing agencies NSFpw NSF International CSA Canadian Standards Assoc UPC IAPMO UL Underwriters Laboratories or others Note Manufacturers may choose the agency or agencies with which they list All of the examples shown are not required on an individual product List of fittings standards with Examples ASTM F 1807 F 1960 which tubing is compatible Manufacturer name or trademark Production code Designation Code F 2080 or others Depends upon manufacturer Depends upon manufacturer PEX 1006 66 Copyright 2006 Plastic Pipe and Fittings Association 66 66 67 Chapter 9 InSTALLATIon Fitting Identification All fittings shall be marked with manufacturers name or trademark or other identification mark plus the ASTM standard specification with which the fitting complies Applicable Standards ASTM F 876 Specification for Crosslinked Polyethylene PEX Tubing ASTM F 877 Specification for Crosslinked Polyethylene PEX Plastic Hot and Cold Water Distribution Systems ASTM F 1807 Specification for Metal Insert Fittings Utilizing a Copper Crimp Ring for SDR 9 Crosslinked Polyethylene PEX Tubing ASTM F 1960 Specification for Cold Expansion Fittings with PEX Reinforcing Rings for use with Crosslinked Polyethylene PEX Tubing ASTM F 2159 Standard Specification for Plastic Insert Fittings Utilizing a Copper Crimp Ring for SDR9 Crosslinked Polyethylene PEX Tubing ASTM F 2080 Standard Specification for ColdExpansion Fittings With Metal CompressionSleeves for CrossLinked Polyethylene PEX Pipe ASTM F 2098 Standard Specification for Stainless Steel Clamps for Securing SDR9 Crosslinked polyethylene PEX Tubing to Metal Insert Fittings CSA B1375 Crosslinked Polyethylene PEX Tubing Systems for Pressure Applications Limitations on PEX Use Do not use in applications where the temperature of the water could exceed 180oF at 100 psi unless specifically approved in the code eg water heater relief line See manufacturers recommendations for higher operating temperatures at lower pressures Do not use in any application where tubing will be exposed to direct sunlight Do not allow tubing to come in extended contact with any of at least the commonly encountered construction materials listed below This list is not allinclusive Pipe thread sealing compounds Fire wall penetration sealing compounds Exception water soluble gypsumbased caulking or other sealants approved by the PEX tube manufacturer Petroleumbased materials or sealants such as Kerosene Benzene Gasoline Solvents Fuel Oils Cutting Oils Asphaltic Paint and Asphaltic Road Materials Acetone Toluene andor Xylene Consult your tubing manufacturer if you have questions about these or any other materials not listed Do not place any PEX tubing in heavily contaminated soils or other heavily contaminated environments 67 Copyright 2006 Plastic Pipe and Fittings Association 69 69 68 Chapter 9 InSTALLATIon i i i i i i i i i ipi i ipi imi i Do not use tub ng w th gouges cuts cracks abras ons evidence of chem cal attack or other defects or tub ng wh ch has been crushed or k nked Do not use PEX in sw mm ng pool p ng systems Copper or brass fitt ngs when used in a PEX p ng system have the same l tat ons as copper or brass fittings used in plumbing or heating systems Store fittings in containers that are free of oil grease lubricants solder flux or other chemicals and away from corrosive atmospheres Example Ammonia TUBING INSTALLATION PRACTICES General Installation Review all limitations on the use of crosslinked polyethylene tubing and the fitting system you have selected to use Keep tubing a minimum of 12 inches vertically or 6 inches horizontally from sources of high heat such as recessed light fixtures flue gas vents or heating appliances Do not install PEX tubing downstream of any pointofuse water heater or immersed coil heater in a boiler where the output temperature can exceed 180oF or closer than 6 inches upstream Contact manufacturer for recommended metallic transition fittings PEX tubing may be connected directly to residential electric water heaters if the local code and manufacturers instructions allow When connecting PEX tube to gas water heaters the tube must be kept at least 6 inches away from the exhaust vent of the heater Flexible metal water heater connectors may be needed in some instances Hose bibbs shall not be supported by PEX tubing Hose bibbs shall be anchored to prevent strain on PEX tubing Use only continuous length tubing no fittings when installing PEX under or within a slab Protect PEX tubing with nonmetallic sleeves where it penetrates a slab or foundation Examples PVC bend guides PE sleeving Protect tubing from nail damage where appropriate Nail plate 68 Copyright 2006 Plastic Pipe and Fittings Association 68 68 69 Chapter 9 InSTALLATIon Bending the Tubing Do not bend PEX tubing tighter than the following minimum recommended bending radii Tubing Size Minimum Bending in nominal Radius in CTS 38 4 12 5 34 7 1 9 NOTE If using tubing in coils and bending the tubing against the coil direction the minimum bending radius is 3 times the radius given above eg 38 tubing 3 x 4 12 Handling and Storing Tubing and Fittings Do not drag the tubing over rough terrain Do not crush or kink the tubing rocks or any surface that can cut puncture or damage the tubing wall Inspect all tubing and fittings before and after installation Cut out and replace all damaged sections or fittings Tubing shall be stored in a way to protect the system from mechanical damage slitting puncturing etc Tubing and fittings shall be stored undercover for cleanliness and to avoid exposure to sunlight Consult manufacturer for recommended limits for outside storage Copyright 2006 Plastic Pipe and Fittings Association 69 71 71 70 Chapter 9 InSTALLATIon Pl i i i Tubing Supports Selection and Inspection ast c hangers and straps are recommended but metal supports wh ch are des gned for use with plastic tubing can be used Do not use supports that pinch or cut the tubing Support should allow free tubing movement Inspect all supports prior to installation to ensure that sharp edges do not exist that can damage the tubing Support Spacing and Location Horizontal Tubing Support Spacing Nominal Tubing Diameter in Spacing in 38 12 34 1 32 Vertical tubing shall be supported at every floor 8feet to 10feet height and at the midfloor guide between floors When penetrating metal studs utilize a properlydesigned bushing or sleeving material on all penetrations to protect tubing Tubing and fittings shall be installed without placing stress on the connection Stress on connections frequently occurs when tubing is not properly strapped at changes of directions ll i See i ustrat ons for proper methods Correct Incorrect Correct 70 Copyright 2006 Plastic Pipe and Fittings Association 70 70 71 Chapter 9 InSTALLATIon ExpansionContraction of Tubing Do not pull tubing tight during installation This can cause excessive tensile forces on fittings and connections when tubing cools and contracts Allow 18inch slack per foot of installed tubing Expansion can usually be accommodated by the tubings flexibility for sizes up to and including 1 inch Hydraulic Shock Pressure Surge The following table provides the maximum pressure that will occur from rapid closure of a valve in the various tubing systems at a given velocity The faster the velocity the greater the potential hydraulic shock pressure surge Excessive hydraulic shock pressure surge may result in audible water hammer with metallic piping systems though this is highly unlikely with PEX tubing due to the flexibility of the tubing itself The table shows the additional hydraulic shock pressure surge that can occur in various types of pipes at the water velocities shown when a fastacting valve closes Hydraulic shock pressure is in addition to the system static pressure measured on site To determine the instantaneous total system pressure that occurs add the hydraulic shock pressure to the static pressure For normal plumbing installations water hammer arrestors are not necessary with a PEX tubing system In predominantly metal piping systems in which PEX is used it may be necessary to install water hammer arrestors Hydraulic Shock psi at 73 F Velocity fps 4 6 8 10 PEX 58 87 116 145 Coppper 200 300 400 505 Galvanized Steel 240 360 475 595 71 Copyright 2006 Plastic Pipe and Fittings Association 73 73 72 Chapter 9 InSTALLATIon ll i ld pl i l i ly si l l i i i i l i l i i i i i i l i i i i ili Manifold Plumbing Systems The para el man fo umb ng concept is re at ve mp e Each faucet or water out et is fed by its own ded cated l ne wh ch runs from a central man fo d By provid ng each out et w th its own d str but on l ne the system offers qu eter water flow more ba anced water pressure a dramat c reduct on in the number of fitt ngs requ red and the ab ty to save both water and energy versus traditional system designs The following information applies to a PEX tubing plumbing manifold system in addition to the general limitations and installation information on PEX tubing and fittings in this manual Manifolds can be installed in a horizontal or vertical position In larger installations with multiple water heaters remote manifolds may be used to handle groups of remote outlets Each faucet or water outlet is fed by its own dedicated line from the manifold which may be located near the water supply or water heater Tubing shall be run continuously and as directly as possible between manifold and fixture locations Approved fittings may be used to repair kinked or damaged PEX distribution lines or to add to a distribution line that was mistakenly cut too short during installation Excessive use of fittings is unnecessary Shutoff valves can be placed at the manifold or fixture Check with your local inspector Tubing shall not be pulled tight Leave slack to allow for expansion and contraction Install tubing cautiously to avoid binding kinking or abrasion Leave excess tubing at the beginning and end of runs for connection to fixtures and the manifolds When running lines to a group of fixtures they may be bundled together but must be bundled loosely enough to allow individual tubing movement Plastic ties may be used Do not use tape when bundling tubing as it may restrict movement of tubing runs When bundled lines pass through conventional structural members cut a hole at the centerline of the member Consult the applicable code for maximum allowable hole size Identify and mark all lines at the manifold 72 Copyright 2006 Plastic Pipe and Fittings Association 72 72 73 Chapter 9 InSTALLATIon This drawing represents a typical manifold system Manifold Plumbing Systems Parallel Water Distribution Manifold Plumbing HomeRun Systems Each faucet or water outlet is fed by its own dedicated line from the manifold Manifolds for hot water should be installed near the water heater to minimize hot water delivery time Manifolds shall be installed at least 36 inches away vertically or 18 inches away horizontally from the water heater A manifold for cold water only may be installed near the water supply The following information applies to a PEX tubing plumbing manifold system in addition to the general limitations and installation information on PEX tubing and fittings in this manual Manifolds can be installed in a horizontal or vertical position In larger installations with multiple water heaters use a manifold at each water heater for the fixtures served by the water heater Tubing shall be run continuously and as directly as possible between manifold and fixture locations Approved fittings may be used to repair kinked or damaged PEX distribution lines or to add additional length to a distribution line that was mistakenly cut too short during installation Excessive use of fittings is unnecessary Shutoff valves may be placed at the manifold or at the fixture Check with your local inspector for the local requirements Tubing shall not be pulled tight Leave slack to allow for expansion and contraction Install tubing cautiously to avoid bending kinking or abrasion Leave excess tubing at the beginning and end of runs for connection to fixtures and the manifolds 73 Copyright 2006 Plastic Pipe and Fittings Association 75 75 74 Chapter 9 InSTALLATIon i i l l l ll i i l ic ti ld li l i i i i is i i i li i i i When runn ng l nes to a group of fixtures they may be bund ed together but must be bund ed loose y enough to a ow ind vidual tub ng movement P ast es may be used Hot and co nes may be bund ed together but some jur sd ct ons do not perm t th pract ce Be sure to check w th the local author ty Do not use tape when bund ng tub ng as it may restr ct movement of tub ng runs When bundled lines pass through conventional structural members cut a hole at the centerline of the member Consult the applicable code for maximum allowable hole size Identify and mark all lines at the manifold Manifolds shall be accessible and protected from freezing and exposure to sunlight Hot water and cold water manifolds shall be sized in accordance with the following table Nominal Size Internal Diameter in Maximum Demand gpm Velocity of 4 fps Velocity of 8 fps 12 2 5 34 6 11 1 10 20 114 15 31 112 22 44 Individual fixture shutoff valves may be installed at the manifold if permitted by the local authority If installed they shall be identified as to the fixture being supplied Individual distribution lines supplied from a manifold and installed as part of a parallel water distribution system shall be sized in accordance with the following table 74 Copyright 2006 Plastic Pipe and Fittings Association 74 74 75 Chapter 9 InSTALLATIon Minimum Sizes of Fixture Water Supply Lines in Manifold Systems Fixture Minimum Pipe Size in Bathtubs and Whirlpool Tubs 12 Tub and Shower 12 Shower only Single Head 38 Bathroom Lavatory 38 Water Closet Residential 38 Water Closet Commercial 12 Kitchen Sink 38 Laundry Washing Machine 38 Utility Sink 38 Bar Sink 38 Urinal Flush Tank 38 Urinal Flush Valve 12 Thawing PEX Tubing Systems PEX tubing systems should not be intentionally subjected to freezing Do not use open torch or excessive heat to thaw PEX tubing Tubing failure or damage can result Use a hot air gun or a blow dryer Heat DO NOT USE A TORCH must be applied directly to the frozen tubing section Temperature on tubing shall not exceed 180oF Several suitable methods exist to thaw PEX tubing They include A commercial system which pumps heated water through the tube to the ice blockage and returns the cooled water for reheating Wet hot towels Hot water Handheld hair dryer Low wattage electrical heating tape 75 Copyright 2006 Plastic Pipe and Fittings Association 77 77 76 Chapter 9 InSTALLATIon i l i i l Pressure Testing and Inspection of the Completed System Test system w th water Test pressure sha l be at least equal to the expected work ng pressure ma n pressure but not ess than 40 psi and not greater than 225 psi at 73F Compressed air testing is only recommended when water is not available or when cold weather could freeze the system Compressed air tests shall include appropriate safety precautions and the test pressure shall not exceed 100 psi PEX tubing is ductile and will not shatter during a pressure test and release shards of plastic However plastic fittings or other system components or unassembled fittings may cause a hazard Check with local codes before using air pressure testing Test duration should not be less than 15 minutes Do not allow water in system to freeze Disinfection of Potable Water Systems If disinfection of the system is required by code and the conditions are not specified the following procedures can be used Chlorine Concentration Disinfection Period Authority 50 to 100 ppm 3 hours AWWA 50 ppm 6 hours ICC American Water Works Association International Code Council Use one of the recommendations above Premix the solution before injection into the system Thoroughly flush all lines of the system at the end of the disinfection period Failure to do so may damage the plumbing system 76 Copyright 2006 Plastic Pipe and Fittings Association 76 76 77 Chapter 9 InSTALLATIon Buried PEX Water Service Lines Fittings Consult manufacturer for proper fittings for water service application Trench Preparation Trench bottom shall be solid with no hollows lumps rocks or other materials that could damage the tubing Laying the Tubing Tubing should be laid with sufficient slack snaking to accommodate any contraction due to cooling prior to backfilling Tubing will expand or contract approximately 1 inch in length for each 10F change in tubing temperature for each 100 feet of tubing Minimum bending radius requirements for PEX tubing shall be followed See Bending the Tubing Table Inspect tubing for damage Remove and replace damaged sections In poor soil conditions such as mud rock black gumbo or clay it is necessary to excavate deeper and use good clean fill or granular fill to smooth the trench bottom Correct Incorrect Incorrect Penetrating Foundation or Basement Walls When PEX is run through a basement or foundation wall it must be protected by a rigid sleeve that spans the distance from within the wall out to the undisturbed soil in the pipe trench The purpose of this protective sleeve is to prevent shearing of the PEX tubing at the wall in the event there is settlement in the backfill around the wall At the point where the sleeve terminates inside the foundation or wall the space between the PEX and the sleeve should be sealed to prevent leakage into the building Note Petroleumbased caulks or sealants should not come in direct contact with PEX Copyright 2006 Plastic Pipe and Fittings Association 77 79 79 78 Chapter 9 InSTALLATIon l i l l i i i ll i lli SlabonGrade Installation Laying and Supporting Tubing under Slab On y cont nuous yrun engths of tub ng w thout fitt ngs sha be used when nsta ng PEX under a slab All connections shall be outside or above the slab Tubing shall be completely buried by a suitable easily compacted backfill material such as sand or pea gravel PEX tubing should be installed under the rebar remesh or tensioning cables in the slab PEX tubing shall be covered or fastened to prevent the tubing from floating or being pulled up to the slab surface PEX tubing does not have to be sleeved its entire length where it lies beneath a slab PEX tubing shall be protected with a nonmetallic sleeve where it comes through the slab Because PEX is flexible it may need support to keep it from falling back onto the slab once it exits the slab To prevent this PEX can be carefully tied to rebar wood stakes or rigid drain pipe for support This will serve to protect the PEX tubing as the slab is poured leveled and smoothed and from subsequent framing and construction work Protection of Tubing and Fittings from UV Exposure after the Pour Due to the nature of slabongrade installations tubing and fittings may be exposed to UV light for unspecified periods of time after the slab is poured and before the structure is framed and enclosed To prevent damage from UV exposure PEX tubing and fittings that are exposed above the slab shall be wrapped with an opaque covering such as black polyethylene bags or sheeting immediately after the pouring of the slab This covering should extend down to the surface of the slab to protect all of the tube above the slab from excessive UV exposure For specific limitations on UV exposure consult the PEX tube manufacturer Backfilling Do not use clay silt or rocky backfill Remove the construction materials trash or foreign objects from trench prior to backfilling The tubing and fittings should be surrounded with good clean fill or sand or river run gravel of 12inch maximum particle size Compact the initial backfill around the tubing to provide adequate tubing support and prevent settlement It is particularly important to adequately compact the soil around the tap connection It is recommended that the tubing be pressurized with water prior to backfilling to reveal any damage 78 Copyright 2006 Plastic Pipe and Fittings Association 78 78 79 12 2 5 34 6 1 4 2 Chapter 9 InSTALLATIon Technical Data Tubing Dimensions and Weights ASTM F 876 F 877 Nominal Size Internal Diameter in Maximum Demand gpm Velocity of 4 fps Velocity of 8 fps 11 10 20 11 15 31 11 22 44 Friction Losses Type of Fitting Equivalent Length of Tubing ft 38 Size 12 Size 34 Size 1 Size Coupling 29 20 06 13 Elbow 90 92 94 94 100 Teebranch 94 104 89 110 Teerun 29 24 19 23 Consult manufacturer for other fitting friction losses Tubing water flow rate velocity and frictional losses are given in the following tables Long radius tubing bends have the same head loss as straight tubing Copyright 2006 Plastic Pipe and Fittings Association 79 81 81 80 Chapter 9 InSTALLATIon 3 1 3 1 2 3 4 5 6 7 8 9 Friction Loss and Velocity vs Flow Rate PEX Plumbing Tubing CTS ASTM F 876 F 877 Nominal Size Average ID 8 0350 2 0475 4 0671 1 0863 GPM Friction Loss Velocity Friction Loss Velocity Friction Loss Velocity Friction Loss Velocity 70 333 16 181 03 096 01 055 254 667 58 362 11 181 03 110 539 1000 122 543 23 272 07 165 918 1334 208 724 39 363 11 219 314 905 59 454 17 274 440 1086 82 544 24 329 586 1267 109 635 32 384 140 726 41 439 174 817 51 494 10 211 907 62 548 11 252 998 74 603 12 296 1089 87 658 13 343 1179 101 713 14 394 1270 116 768 15 132 823 16 148 878 NOTE Friction Loss based on HazenWilliams Formula C 150 CTS Tubing manufactured per ASTM F 876F 877 Friction Loss F Loss is expressed as psi per 100 ft of tubing Velocity VEL feet per second 80 Copyright 2006 Plastic Pipe and Fittings Association 80 80 81 Chapter 9 InSTALLATIon Connection Transition to Other Piping Materials Solder copper transition fittings onto the copper pipe and allow cooling before connecting to PEX tubing High heat greater than 180F may damage the PEX tubing Do not use plastic male threads or nongasketed female threads when making a connection to metal threads Use only manufacturers recommended transition fittings When making connections to CPVC pipe or fittings use only approved transition fittings Joining Procedures Utilizing Metallic or Polymer Insert Fittings Insert Fitting with a Black Copper Crimp Ring ASTM F 1807 OR ASTM F 2159 Making a Connection 1 Cut tubing squarely remove burrs and slip the copper crimp ring onto the tube 2 Insert fitting into tube to the tube stop do not apply lubricant or pipe dope on the insert fitting Position crimp ring 18 to 14 inch from end of tubing To prevent ring from moving squeeze the ring slightly with your fingers or a pair of pliers 3 Center crimping tool jaws over the ring Keeping both ring and tool square with tube close the tool completely DO NOT CRIMP TWICE 4 It is recommended that the finished crimps be checked with the appropriate GO NOGO gauge Slip gauge squarely over the crimped ring If the GO slot of the gauge doesnt fit across the crimped ring the diameter of the ring is too large and the fitting must be cut out DO NOT RECRIMP 5 If the NOGO slot of the gauge fits across the crimped ring the diameter of the ring is too small and the fitting must be replaced Cut out the ring and fitting and replace them Incorrect Connections The consequence of not following correct procedures is a potential for leaks Ring crimped over end of tube Result Doesnt cover enough ribs andor tool could crush or crack fitting Tool not at 90 degrees to tube when crimped Result Insufficient rib coverage tubing dented Ring not completely covered by crimp tool Result Ring distortion nonuniform crimp Tubing not cut squarely Result Insufficient rib coverage Ring too far from pipe end Result Insufficient rib coverage 81 Copyright 2006 Plastic Pipe and Fittings Association 83 83 82 Chapter 9 InSTALLATIon l i i Al l ll i l i il Tools and Rings Use too s recommended by fitt ng and tub ng manufacturers l too s must make a fu c rc e cr mp Check tool adjustment at least da y and readjust as necessary Use only blackcolored crimp rings designed for this PEX system Joining Procedures Utilizing ASTM F 1960 Fittings and PEX Rings 1 Cut the PEX tubing perpendicular to the length of the tubing using a cutter designed for plastic tubing Remove all excess material or burrs that might affect the fitting connection 2 Slide the PEX Ring over the end of the tubing 3 The PEX Ring should extend over the end of the tubing no more than 116 inch The end of the tubing and inside of the PEX Ring must be dry and free of grease or oil to prevent the PEX Ring from sliding out of place during expansion 4 Place the free handle of the tool against your hip or place one hand on each handle when necessary Fully separate the tool handles and insert the expander head into the end of the tubing until it stops Be sure you have the correct size expander head on the tool Full expansion is necessary to make a proper connection Bring the handles together to expand Separate the handles remove the head from the tubing and rotate it 18 turn Slide the tool head into the tubing in the newly rotated position and expand again 5 Repeat the expansion process until the tubing and ring are snug against the shoulder on the expander head 6 Immediately remove the tool and slide the tubing over the fitting until the tubing reaches the stop on the fitting As you slide the tubing over the fitting you should feel some resistance If the tubing reaches the shoulder of the fitting without any resistance the tubing may be overexpanded and may require additional time to fully shrink over the fitting To ensure a proper connection the PEX Ring must be seated up against the shoulder of the PEX fitting 82 Copyright 2006 Plastic Pipe and Fittings Association 82 82 83 Chapter 9 InSTALLATIon 7 At minimum ASTM F 1960 connections must be pressure tested to the systems working pressure PEX tubing and fittings are safe for air and hydrostatic testing Refer to your local code for additional requirements ASTM F 1960 Connections Helpful Hints Holding the tubing in the expanded position increases the time it takes for the tubing to shrink around the fitting The tubing should hold the fitting firmly after just a few seconds If the fitting appears loose for more than a few seconds the tubing has been overexpanded If there is more than 116 inch between the PEX Ring and the fitting square cut the tubing 2 inches away from the fitting and make another connection using a new PEX Ring Incorrect Ring does not meet the pipe stops on the fitting Tubing and rings should both meet the pipe stops on the fitting Incorrect Tubing does not meet the pipe stops on the fitting Tubing and rings should both meet the pipe stops on the fitting Incorrect Tubing and ring do not meet the pipe stops on the fitting Tubing and rings should both meet the pipe stops on the fitting Tubing is not cut square Copyright 2006 Plastic Pipe and Fittings Association 83 85 85 84 Chapter 9 InSTALLATIon i l i i li l i Tools There are a var ety of PEX expander too s that are des gned for ease of use when mak ng re ab e permanent connect ons Joining Procedures Utilizing ASTM F 2080 Fittings and Compression Sleeves Summary Fittings shall be joined to PEX pipe by first expanding the end of the pipe with the expander tool inserting the coldexpansion fitting into expanded pipe then pulling the compression sleeve over the PEX pipe and the fitting compressing the pipe between the compression sleeve and the fitting Procedure 1 Slide the compression sleeve onto the pipe so that the insidebeveled end is facing toward the end of the pipe Slide the compressionsleeve far enough down the pipe so that it will not prevent expansion of the pipe 2 Insert the head of the expander tool into the pipe The expander tool segments shall be centered inside the pipe 3 Fully expand the pipe holding it open for approximately 3 seconds and remove the tool Rotate the tool approximately 30 insert the expandertool into the pipe and repeat the expansion process This ensures that the pipe is round inside 4 The coldexpansion fitting should be inserted within 30 seconds of the expansion otherwise the pipe will shrink back to its original size and become too small for fitting expansion The fitting is properly inserted when the PEX pipe is pushed up against the last rib of the coldexpansion fitting If full insertion is not possible remove the cold expansion fitting immediately and expand the pipe again for 3 seconds 5 When the expansion is complete and the coldexpansion fitting is inserted properly into the PEX pipe the metal compression sleeve shall be pulled over the fitting with the compression tool this may be the same tool as the expander tool or a separate tool 84 Copyright 2006 Plastic Pipe and Fittings Association 84 84 85 Chapter 9 InSTALLATIon 6 Use the compression tool to pull the compression sleeve over the coldexpansion fitting and the PEX pipe end until the sleeve touches the collar of the fitting or until the tool stops 7 The maximum allowable gap between the edge of the compression sleeve and the collar of the coldexpansion fitting shall be 0040 in If this gap is too large then repeat the compression step andor adjust the tool Other Fitting Systems Some PPFA Members have proprietary fitting systems for which ASTM standards have not been written These systems are typically listed as meeting the performance requirements of ASTM F 877 for PEX systems but their fitting dimensions and materials have not been specified in a standard These fittings are typically available only through a single manufacturer and the components of the system do not interchange with similar looking parts from a different manufacturer When using these systems users are cautioned to be sure they do not mix components from different manufacturers even if they look the same 85 Copyright 2006 Plastic Pipe and Fittings Association 87 87 86 Chapter 9 InSTALLATIon 86 Copyright 2006 Plastic Pipe and Fittings Association 86 86 87 10 TESTIMonIALS Don Carpenter Director of Product Development Oakwood Homes of Denver Colorado As part of the Partnership for Advancing Technology in Housing PATH Program administered by the US Department of Housing and Urban Development HUD a Field Evaluation of technologies was conducted at Green Valley Ranch in Denver Colo According to Don Carpenter of Oakwood Homes the company began using PEX piping with a central manifold and homerun system in 2000 after hearing of reduced labor shortened construction cycle time and decreased longterm costs However cost savings isnt the only reason the company chooses PEX pipe We look at it from a quality standpoint said Carpenter director of product development Its less money to install and its a superior plumbing system For the homeowner its control over every fixture in the house and the ability to easily adapt the plumbing when adding fixtures building additions to the house or finishing the basement Oakwood saves the buyers an average of 800 per home because of the PEX piping system chosen for the indoor plumbing system Rodney Ketzner Plumbing Supervisor Plumbing Specialists Inc Wichita Kansas The system goes in almost twice as fast as copper systems After a new house has been framed I walk through the house with the homebuyer to discuss fixtures and plumbing issues including manifold plumbing systems using PEX We offer conventional copper as an option but after I explain the system and the benefits it offers homebuyers almost always choose it My customers also like the quietness of the system Its designed with both the homeowner and the plumbing contractor in mind 87 89 89 88 Chapter 10 TESTIMonIALS Kenny Hodges Owner Hodges Plumbing Blackshire Georgia The owner said it was a good system and hes right I wish I had used it in my own home Alan Boone Plumber Middleton Plumbing Statesboro Georgia My supplier mentioned that we could save a lot of time on installation with the PEX plumbing system The PEX we used was much easier to install and required very few fittings The red and blue colorcoded pipe also made the installation go in quickly and easily identified hot and cold lines Its a great choice on largescale projects If wed gone with copper wed still be there working Tony Partusch Shop Foreman Partusch Plumbing Anchorage Alaska With our climate copper doesnt work very well We see a lot of problems with copper sweat joints leaking With PEX systems weve been able to eliminate 90 percent of the copper sweat joints in a system and now the chance of having a leak at a sweat joint is nearly nonexistent Usually you have to pay a lot more when you upgrade to a better product but PEX manifold plumbing systems are easy to sell because its a better product for about the same price Jim Manning President Interstate Plumbing Air Conditioning Las Vegas Nevada PEX tubing is clean doesnt corrode and its not affected by corrosive water and soil It even comes with a 25year warranty We wanted a system that would save us time eliminate our copper theft problem and ensure quality and reliability PEX has proven itself to be a system that can do all this and more Don George Owner Modern Plumbing Portland Oregon Weve been installing PEX for years in custom homes We utilize manifolds in most of our installations and our customers are continually impressed with how quiet the system is Chris McGinnis Owner Tucson Plumbing and Heating Tucson Arizona The PEX connection is the most positive connection available My plumbers can tell just by looking at the fitting if theyve made a good connection With PEX the installation is fast and easy and the tubing can be buried directly in concretesomething the codes wont allow us to do with copper My plumbers like the ease of installation provided by the PEX fitting and the time savings that result Rigid systems require more connections and more time without the assurance of a positive connection With PEX we have eliminated many of our callbacks which is also a nice benefit 88 88 88 89 Chapter 10 TESTIMonIALS Vince Lopoarchio and Levon Paul Plumber and Project Foreman VHL Plumbing Burbank California Second generation plumber Vince Lopoarchio states The best thing is there are no leaks so when were done were done VHL and the developer benefited with consistent connections no leaks flexible pipe no solder no flux and no flame which made for a cleaner more secure and faster installation process Running 1 inch 34 inch and 12 inch PEX tubing four installers can complete four typical condo units per day keeping VHL ahead of schedule Veteran installer and project foreman Levon Paul says The PEX system is very quiet so our customers are happy Its a pleasure working with this system after 30 years of working with copper I would tell anybody that with PEX technology labor savings the hand tools will pay for themselves on the first multiunit job 89 91 91 90 Chapter 10 TESTIMonIALS 90 90 90 91 11 oTHEr APPLICATIonS Radiant Floor Heating Systems Hydronic radiant floor heating employs heated water flowing through flexible PEX pipes mounted inside or under the floor The heated surface then functions as a radiator warming a room and all objects and people in it This type of heating provides superior comfort and efficiency Figure 111 Radiant Floor Heating Piping compared to traditional forced air convection heating The heating profile is much more uniform meaning fewer cold hot spots Municipal Water Service Pipe In addition to supplying water within the home PEX pipe is also used to distribute water to entire communities through municipal water service pipes Because PEX pipe is more flexible than other piping materials it ensures highimpact resistance with normal backfill PEX pipe is resistant to freeze damage lessening the chance of splitting or cracking It connects to standard compression joints valves and fittings so its easy and convenient to install It can save up to half the cost of coppera significant savings for budgetconstrained city planners 91 93 93 Chapter 11 oTHEr APPLICATIonS 92 Chapter 11 oTHEr APPLICATIonS Snow and Ice Melt PEX pipe can be used to create a hydronic system designed to augment the removal of snow and ice by circulating a heat transfer fluid usually antifreeze and water through pipes installed within outdoor surfaces Common applications are for driveways sidewalks hospital entrances parking garage ramps wheelchair ramps car washes hot tubpool surrounds and runways Benefits include reduced maintenance costs no snow removal costs reduced liability and obvious convenience Figure 112 Snow and Ice Melt Piping for a Driveway Turf Conditioning PEX pipe is installed within the soil layer of the turf and fluid is circulated at varying temperatures to gently warm the roots to provide optimal root zone temperature PEX pipe can extend the growing season of natural grass surfaces in applications such as golf courses and other sports field surfaces Similar systems are also used in greenhouse applications with bedding plants and other foliage Figure 113 Turf Conditioning in a Stadium 92 92 92 Chapter 11 oTHEr APPLICATIonS 93 Chapter 11 oTHEr APPLICATIonS Fire Suppression ULapproved PEX piping and fitting systems can be used to supply water to fire suppression sprinklers for residential applications While many sprinkler systems are largely independent from the water distribution system for some building types they can be combined with a buildings coldwater plumbing system This has the potential to reduce the installation costs Sprinklers PEX piping and fittings must comply with National Fire Protection Association NFPA requirements for residential fire sprinkler systems and local codes should be consulted when implementing Figure 114 Fire Sprinkler with any fire suppression system to ensure that PEX andor combined PEX Piping systems are permitted for your building type 93 95 95 94 Chapter 11 oTHEr APPLICATIonS 94 94 94 95 A Appendix PErForMAnCE TEST SETuP And dATA Diagrams of piping layouts for different test runs Figure A1 Water System Test Piping Layout Trunk and Branch 60 to TF 95 97 97 Appendix A PErForMAnCE TEST SETuP And dATA 96 Appendix A PErForMAnCE TEST SETuP And dATA Figure A2 Water System Test Piping Layout Trunk and Branch 100 to TF Figure A3 Water System Test Piping Layout HomeRun 60 to TF 96 96 96 Appendix A PErForMAnCE TEST SETuP And dATA 97 Appendix A PErForMAnCE TEST SETuP And dATA Figure A4 Water System Test Piping Layout HomeRun 100 to TF Figure A5 Water System Test Piping Layout Remote Manifolds 60 to TF 97 99 99 Appendix A PErForMAnCE TEST SETuP And dATA 98 it it i i Fi ipi i l 98 Appendix A PErForMAnCE TEST SETuP And dATA Table A1 Simultaneous Flow Performance Data 100 Maximum Length 60 and 80 psi Source Pressure Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pres Cold Flow Cold Pres gpm gpm gpm psi gpm psi gpm psi Trunk and Branch 100 60 psi Static 00 00 00 600 00 543 00 554 TF 25 05 21 600 22 500 03 552 TFLav 43 18 25 600 22 491 03 535 TFWC 68 46 22 600 22 501 02 465 TFK 43 15 28 600 22 492 03 549 TFSh2 52 16 36 600 21 479 03 548 TFSh2K 69 27 42 600 21 474 03 545 TFSh2K tLav 86 42 44 600 21 471 03 521 TFSh2K tLavWC 125 72 53 600 21 444 02 445 gure A6 Water System Test P ng Layout Remote Man fo ds 100 to TF 98 98 Appendix A PErForMAnCE TEST SETuP And dATA 99 Appendix A PErForMAnCE TEST SETuP And dATA Table A1 Simultaneous Flow Performance Data 100 Maximum Length 60 and 80 psi Source Pressure continued Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pres Cold Flow Cold Pres gpm gpm gpm psi gpm psi gpm psi Remote Manifold 100 00 00 00 600 00 542 00 552 60 psi Static TF 25 05 21 600 22 497 03 549 TFLav 4l3 17 26 600 22 490 03 541 TFWC 68 47 21 600 22 501 02 496 TFKit 43 16 27 600 22 491 03 548 TFSh2 52 17 35 600 22 484 03 547 TFSh2Kit 69 28 40 600 21 479 03 543 TFSh2KitLav 86 42 44 600 21 472 03 531 TFSh2KitLavWC 125 74 51 600 21 463 02 478 HomeRun 100 60 psi Static 00 00 00 600 00 541 00 551 TF 25 05 21 600 21 464 03 548 TFLav 43 15 28 600 21 463 03 547 TFWC 68 46 21 600 21 471 03 546 TFKit 43 14 29 600 21 462 03 547 TFSh2 52 17 35 600 21 457 03 547 TFSh2Kit 69 27 41 600 21 453 03 546 TFSh2KitLav 86 39 47 600 21 450 03 544 TFSh2KitLavWC 125 77 48 600 21 456 03 539 Trunk and Branch 100 00 00 00 800 00 745 00 754 80 psi Static TF 29 04 25 800 26 687 03 751 TFLav 50 20 30 800 26 679 03 730 TFWC 78 55 23 800 26 694 03 624 TFKit 50 17 33 800 26 685 03 750 99 101 101 Appendix A PErForMAnCE TEST SETuP And dATA 100 Appendix A PErForMAnCE TEST SETuP And dATA it i i it it i i it it i i i l i l l i l l i Ki i iti l i l l l i i Table A1 Simultaneous Flow Performance Data 100 Maximum Length 60 and 80 psi Source Pressure Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pres Cold Flow Cold Pres gpm gpm gpm psi gpm psi gpm psi TFSh2 60 18 41 800 26 679 03 748 TFSh2K 79 29 50 800 25 663 03 743 TFSh2K tLav 99 48 52 800 25 652 03 713 TFSh2K tLavWC 144 83 61 800 24 616 03 609 Remote Manifold 100 80 psi Static 00 00 00 800 00 746 00 754 TF 29 05 24 800 26 687 03 751 TFLav 50 19 31 800 25 673 03 740 TFWC 78 55 23 800 26 689 03 676 TFK 50 17 32 800 26 682 03 748 TFSh2 60 18 41 800 25 672 03 748 TFSh2K 79 341 48 800 25 659 03 745 TFSh2K tLav 99 48 51 800 25 650 03 727 TFSh2K tLavWC 144 86 58 800 25 630 03 650 HomeRun 100 80 psi Static 00 00 00 800 00 745 00 753 TF 29 04 25 800 25 636 03 750 TFLav 50 17 33 800 25 633 03 748 TFWC 78 53 26 800 25 644 03 746 TFK 50 17 33 800 25 634 03 748 TFSh2 60 17 42 800 25 626 03 748 TFSh2K 79 30 49 800 24 620 03 747 TFSh2K tLav 99 45 54 800 24 615 03 745 TFSh2K tLavWC 144 89 55 800 24 620 03 738 TF Test Shower F xture 15 e evat on Lav Lavatory both va ves open 15 e evat on WC Water C oset tank type 15 e evat on Kit tchen m dpos on 4 e evat on Sh2 2nd Shower fu l open va ve 5 e evat on cont nued 100 100 100 Appendix A PErForMAnCE TEST SETuP And dATA 101 Appendix A PErForMAnCE TEST SETuP And dATA Table A2 Simultaneous Flow Performance Data 60 Maximum Length 60 and 80 psi Source Pressure Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pres Cold Flow Cold Pres gpm gpm gpm psi gpm psi gpm psi Trunk and Branch 60 00 00 00 600 00 542 00 551 60 psi Static TF 25 05 21 600 22 508 03 549 TFLav 43 18 25 600 22 499 03 537 TFWC 68 47 21 600 22 508 02 465 TFKit 43 14 30 600 22 499 03 486 TFSh2 52 16 35 600 22 487 03 547 TFSh2Kit 69 27 42 600 21 480 03 545 TFSh2KitLav 86 42 44 600 21 477 03 524 TFSh2KitLavWC 125 73 52 600 21 460 02 465 Remote Manifold 60 00 00 00 600 00 540 00 552 60 psi Static TF 25 05 20 600 22 506 03 550 TFLav 43 17 26 600 22 501 03 545 TFWC 68 47 21 600 22 509 03 517 TFKit 43 17 27 600 22 502 03 548 TFSh2 52 16 36 600 22 492 03 547 TFSh2Kit 69 27 42 600 22 485 03 544 TFSh2KitLav 86 41 45 600 21 480 03 535 TFSh2KitLavWC 125 75 50 600 21 474 02 497 HomeRun 60 60 psi Static 00 00 00 600 00 276 00 285 TF 25 05 20 600 22 488 03 549 TFLav 43 15 28 600 22 486 03 548 TFWC 68 48 20 600 22 493 03 546 101 103 103 Appendix A PErForMAnCE TEST SETuP And dATA 102 Appendix A PErForMAnCE TEST SETuP And dATA Table A2 Simultaneous Flow Performance Data 60 Maximum Length 60 and 80 psi Source Pressure continued Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pres Cold Flow Cold Pres gpm gpm gpm psi gpm psi gpm psi TFKit 43 17 27 600 22 485 03 548 TFSh2 52 17 35 600 21 478 03 548 TFSh2Kit 69 27 42 600 21 473 03 546 TFSh2KitLav 86 40 46 600 21 469 03 545 TFSh2KitLavWC 125 78 46 600 21 475 03 540 Trunk and Branch 60 00 00 00 800 00 746 00 754 80 psi Static TF 29 04 25 800 26 699 03 752 TFLav 50 20 30 800 26 689 03 738 TFWC 78 55 23 800 26 702 03 664 TFKit 50 17 33 800 26 694 03 750 TFSh2 60 18 42 800 26 682 03 751 TFSh2Kit 79 29 50 800 25 669 03 747 TFSh2KitLav 99 47 52 800 25 661 03 721 TFSh2KitLavWC 144 84 60 800 25 634 03 636 Remote Manifold 60 00 00 00 800 00 745 00 753 80 psi Static TF 29 05 24 800 26 702 03 751 TFLav 50 18 31 800 26 690 03 744 TFWC 78 56 22 800 26 702 03 699 TFKit 50 18 32 800 26 694 03 749 TFSh2 60 19 41 800 26 684 03 748 TFSh2Kit 79 29 50 800 25 667 03 745 TFSh2KitLav 99 46 53 800 25 660 03 734 TFSh2KitLavWC 144 87 57 800 25 645 03 677 102 102 102 Appendix A PErForMAnCE TEST SETuP And dATA 103 Appendix A PErForMAnCE TEST SETuP And dATA Table A2 Simultaneous Flow Performance Data 60 Maximum Length 60 and 80 psi Source Pressure continued Fixture Flow Total System Flow Cold Supply Flow Hot Supply Flow Main Pressure Test Fixture Shower Hot Flow Hot Pres Cold Flow Cold Pres gpm gpm gpm psi gpm psi gpm psi HomeRun 60 80 psi Static 00 00 00 800 00 745 00 753 TF 29 05 24 800 25 669 03 751 TFLav 50 16 34 800 25 663 03 750 TFWC 78 54 25 800 25 673 03 747 TFKit 50 16 34 800 25 664 03 749 TFSh2 60 18 42 800 25 658 03 750 TFSh2Kit 79 29 50 800 25 648 03 748 TFSh2KitLav 99 45 55 800 25 638 03 746 TFSh2KitLavWC 144 90 54 800 25 642 03 739 TF Test Shower Fixture 15 elevation Lav Lavatory both valves open 15 elevation WC Water Closet tank type 15 elevation Kit Kitchen midposition 4 elevation Sh2 2nd Shower full open valve 5 elevation 103 105 105 104 Appendix A PErForMAnCE TEST SETuP And dATA 104 104 104 105 B Appendix InSTALLATIon CHECKLIST q l q l i ini q i ipi q imi q l i q Pl ipi i q Pl i l l i q i i q in pipi ll ll i i i q i ls q i i q l i q i i q i i i l l i li le DESIGN Consu t Local Codes Se ect P pe and Jo ng System Des gn P ng System Opt ze Home Layout Se ect Appropr ate System an P ng Rout ng an Man fo d and Va ve Locat ons Est mate Mater al and Order TRAINING Tra ng insta ers on insta at on techn ques and fitt ngs Order or rent fitt ng too INSTALLATION Rece ve mater al and store as recommended by manufacturer Insta l per manufacturer recommendat ons Pressure test per manufacturer recommendat ons and code requ rements FOLLOW UP Instruct homeowner on locat on and operat on of man fo d va ves f app cab 105 107 107 106 Appendix B InSTALLATIon CHECKLIST 106 106 106 107 C Appendix rESourCES Articles and Reports 1 Automated Builder Magazine PEX Pipe Gains Popularity for Practical Purposes April 2005 page 40 This article presents the multitude of advantages to using PEX plumbing water supply systems in residential construction and discusses the standards and certifications required for PEX pipe and fittings One home builders experience with PEX and a manifold system is described 2 Couch Toro Oliphant and Vibien Chlorine Resistance Testing of UV Exposed Pipe Jana Laboratories Ontario Canada 2002 Chlorine Resistance CR testing is used to determine the impact of accelerated UV exposure on the oxidative resistance of crosslinked polyethylene PEX pipe Following accelerated UV exposure samples were tested to failure under accelerated test conditions to simulate chlorinated potable water For the particular material examined it was demonstrated that excellent retention of oxidative stability was achieved when suitable UV protection was employed 3 Kempton William Residential Hot Water A BehaviorallyDriven System Energy Volume 13 Number 1 January 1988 pages 107114 This article reports on the results of monitoring the hot water use in seven homes over 718 months The study shows the wide variation in hot water use among the different project participants For instance water consumption ranged from 445 liters per day per person to 1264 liters per day per person Bathing comprised the largest single water use in all homes but duration and volume varied significantly The study points to the potential for water and energy savings through modification of behavior but also notes that habits related to hot water usage have deep roots in personal social and cultural values The study also found that most of the participants had misperceptions related to the duration and amount of their water usage and did not have a firm understanding of the costs of hot water 107 109 109 Appendix C rESourCES 108 l l i il i i l l i i l iscipli i i 4 Korman Thomas M et al Knowledge and Reasoning for MEP Coordination Journal of Construction and Engineering Management Vo ume 129 Number 6 NovemberDecember 2003 pp 627634 Current y des gners and constructors use ta ored CAD systems to des gn and fabr cate MEP systems but no know edge based computer techno ogy ex sts to ass st in the mu tid ne MEP coord nat on Appendix C rESourCES effort The paper describes results from a research project to capture knowledge related to design criteria construction operations and maintenance of MEP systems and apply this knowledge in a computer tool that can assist designers and builders in resolving coordination problems for multiple MEP systems This work might provide background information relevant to developing a knowledgebased design tool for residential plumbing distribution systems 5 NSF International Frequently Asked Questions on Health Effects of PEX Tubing This article explains who NSF International is provides information on NSF Listed Products for potable water applications and describes applicable NSFANSI standards for testing and evaluation of potable plumbing 6 Okajima Toshio Computerized Mechanical and Plumbing Design Actual Specifying Engineer Volume 33 Number 6 June 1975 pp 7883 Many mechanical and plumbing systems designs are based on the engineers past experience or educated guesses The author tells how one firm developed a computer program for plumbing and heating ventilating and air conditioning design 7 Orloski MJ and Wyly RS Performance Criteria and Plumbing System Design National Engineering Lab Washington DC 1978 An overview is presented indicating how the performance approach to plumbing system design can be used to extend traditional methods to innovative systems Some of the mathematical models now used for system design and pipe sizing in plumbing codes are reviewed in the context of performanceoriented research Conceivably the reexamination by plumbing designers of traditional design criteria against measured user needs could be beneficially extended to other areas of plumbing design such as water distribution storm drainage and plumbing fixtures Beyond this it has been recognized that uniform guidelines for evaluation of innovative systems based on research findings are essential for wide acceptance of performance methods particularly by the regulatory community 8 Rubeiz Camille Flexing Your PEX Plumbing the Possibilities of Cross linked Polyethylene Pipes Modern Materials Vol 2 No 2 November 2004 pages 58 Properties of PEX pipe are described as well as benefits of using PEX for potable water supply plumbing systems Parallel piping and central manifold system installations are discussed Real and misconceived limitations are also presented In addition other applications for PEX pipe systems such as snow and ice melt and turf conditioning are mentioned 9 Rubeiz Camille Ball Michael Warming Up to PEX Pipe Radiant Heating Systems Modern Materials Vol 2 No 1 May 2004 pages 1418 The article describes how radiant heating works and compares the radiant heat distribution to traditional baseboard or forced air systems There is a general description of the three methods of crosslinking polyethylene to form PEX piping radiation peroxide 108 108 108 Appendix C rESourCES 109 il li l i i i i i i i ll icl i i ll i i i i i li j and s ane processes App cab e ASTM and CSA standard spec ficat ons for test ng of PEX p pe and fitt ngs are l sted F na y the art e br efly d scusses the insta at on of PEX rad ant heat ng systems in new resident al construct on or remode ng projects 10 Steele Alfred Plumbing Design Has Ma or Impact on Energy Appendix C rESourCES Consumption Specifying Engineer Volume 45 Number 6 June 1981 pages 80 83 The paper discusses the potential energy savings that could result from lowflow fixtures pipe insulation and water heater temperature settings The author emphasizes that significant water savings and therefore energy savings as well could be achieved with no inconvenience to the enduser It was not until 1994 that the first lowflow fixtures were introduced in the United States after being federally mandated 11 Stewart William E et al Evaluation of Service Hot Water Distribution system Losses in Residential and Commercial Installations Part 1 FieldLaboratory Experiments and Simulation Model and Part 2 Simulations and Design Practices ASHRAE Transactions Volume 105 1999 The papers describe a numerical model developed to estimate the heat loss or gain from insulated and uninsulated copper and steel hot water pipes The authors contend that the simulation model is a more reliable and consistent method of estimating such losses due to the difficulty of accurately measuring small temperature differences in field and laboratory experiments The results of the simulation model correlate closely with previously published data specifically 1997 ASHRAE Handbook Fundamentals and 1995 ASHRAE Handbook HVAC Applications The simulation results showed more than a 50 percent decrease in heat loss in hot water piping that was insulated within approximately three feet of the water heater and that increasing the length of pipe insulated does not significantly decrease heat loss further 12 Tao William Associates Plumbing System Design Heating Piping Air Conditioning Volume 59 Number 3 March 1987 pp 101114 This article outlines the fundamental criteria to be considered in the design of a building plumbing system These criteria include load calculations system sizing and special design applications A procedure for plumbing system design is also introduced that may serve as a comprehensive basis for developing computer aided design programs 13 Vibien Couch Oliphant et al Assessing Material Performance in Chlorinated Potable Water Applications Jana Laboratories Ontario Canada In this study the nature of the failure mechanism of crosslinked polyethylene PEX pipe material exposed in the laboratory to chlorinated potable water was examined Based on this study the PEX pipe material appears to have good resistance to chlorinated potable water 14 Wendt RL Evelyn Baskin David Durfee Evaluation of Residential Hot Water Distribution Systems by Numeric Simulation Buildings Technology Center Oak Ridge National Laboratory for the California Energy Commission Oak Ridge TN 2004 This study simulated and compared the energy and water performance economics and barriers to use of various domestic hot water distribution systems in California homes Variation in systems included trunk and branch manifold systems copper pipe CPVC pipe PEX piping insulated and uninsulated pipe attic location slab 109 111 111 Appendix C rESourCES 110 l i i l i i i l i i l i ll i l l i l i ipi l ocat on demand rec rcu at on and cont nuous rec rcu at on Us ng a computer mode LabV ew the fo ow ng resu ts were found for a c ustered hot water usage pattern a Demand rec rcu at on systems whether p ng was copper or CPVC wasted the east water and the least energy Appendix C rESourCES b Whether copper or CPVC piping was used the system with a centrally located water heater was second with respect to the least amount of energy wasted However almost twice as much water was wasted in comparison to the recirculation systems even though the water heater was centrally located c In both groups the CPVC systems were slightly better energy performers than their copper counterparts about 4 to 14 percent better d The parallel pipe configurations using PEX tubing wasted about 3 percent more energy than uninsulated copper pipe in an attic installation but wasted 60 percent less energy than uninsulated copper installed in a slab Insulating the subslab copper pipe brought its energy performance inline with the PEX system With respect to water waste the parallel system attic installation performed similarly to copper pipe installed in an attic e Subslab installation without insulation compromised the energy and water performance of all the systems However the parallel system using PEX pipe suffered the least an approximate 30 percent drop in performance compared to a fourfold decrease for the copper and CPVC systems f Construction costs for the parallel system using PEX tubing were slightly lower than the trunk and branch system using copper but higher than the CPVC systems While the study indicates that usage patterns have the most significant effect upon energy usage and water consumption in residential situations it also postulates that parallel pipe distribution systems may offer an attractive alternative for some house designs and distribution system layouts The modeling showed very little difference in energy and water performance when clustered use was assumed but indicated that parallel systems outperform conventional trunk and branch systems when cold starts are typical 15 Wiehagen J and Sikora J March 2003 Performance Comparison of Residential Hot Water Systems work performed by NAHB Research Center Inc for NREL Using data from two research sites in Ohio and from weekly laboratory experimental data a simulation model was developed to estimate annual energy consumption for several types of waterheating systems Using the Transient Energy System Simulation Tool TRNSYS three types of systems were analyzed under high usage average 76 gallons per day and lowusage conditions average 28 gallons per day The systems were 1 a standard electric storage tank water heater with a copper treeconfiguration distribution system 2 a central tankless water heater with a polyethylene PEX piping parallel distribution system and 3 multiple pointofuse water heaters with a copper treetype distribution system The simulations showed a 12 percent increase in overall system efficiency for the tankless water heater with the PEX parallel piping system compared to the storage heater with the copper treed system under high usage conditions For the lowuse home there was a 26 percent 110 110 110 Appendix C rESourCES 111 i i l is al i i ll ipi i i i i l i i i l i i ltipl i l i ncrease in effic ency for the same system The ana ys so ind cated energy sav ngs for the PEX para el p ng configurat on whether the water heat ng equ pment was a convent onal tank or a tank ess system 6 percent sav ngs for the h ghuse home and 13 percent sav ngs for the lowuse home Ana ys s of the treetype system w th mu e po ntofuse heaters a so showed improved energy performance in compar son Appendix C rESourCES to a similar treed distribution system with a storage tank water heater a 50 percent reduction in energy consumption for the lowuse condition and 28 percent reduction for the highuse home In addition to the energy savings an economic analysis showed a positive annual cash flow for the parallel distribution systems whether a tank or tankless heater was used compared to the standard tanktree system The analysis included estimates of installed cost financing costs and electricity costs 16 Wiehagen J and Sikora J April 2002 Domestic Hot Water System Modeling for the Design of Energy Efficient Systems work performed by NAHB Research Center Inc for NREL Using data obtained from actual home sites the researchers developed a computer simulation model to analyze typical residential plumbing systems The evaluation compared demand water heating equipment in conjunction with various piping configurations to a standard tank heater with a tree delivery system High and lowusage patterns were considered Maximum energy savings resulted from using a combination of a centrally located demand water heater with a parallel piping system Annual energy savings were 17 percent for the high consumption home and 35 percent for the low use home The demand system did show some hot water temperature degradation during periods of high flow rates 17 Wyly RS et al May 1975 Review of Standards and Other Information on Thermoplastic Piping in Residential Plumbing Sponsored by the US Department of Housing and Urban Development Washington DC The paper is a review of existing information on the physical characteristics of thermoplastic piping that are of particular interest in considering its potential for use in residential aboveground plumbing The presentation is oriented to considerations of adequacy of functional performance of plumbing systems from the usersowners viewpoint in contrast with the typical productspecifications oriented format reflected in current standards Not only are the physical characteristics emphasized that relate most directly to the determination of functional performance of installed systems but the importance of design and installation detail in the context is discussed In conclusion this review indicates the need for better use of existing knowledge as well as for some research and test development work particularly in the areas of thermal properties response to building fires and resistance to water hammer Manufacturers Information 1 IPEX Inc PlumbBetter IPEX Piping Systems Installation Guide Denver CO The guide provides installation guidelines and product specifications regarding thermal expansion bending radius cutting and joining instructions firestop ratings and pressure drop and flow rate specifications The document does not give guidance on system design or layout specifically stating that the method of plumbing a residence or commercial project is left to the discretion of the designer contractor or developer 111 113 113 Appendix C rESourCES 112 i li il i izi l i i i i i i l l i i i irl i i li i l i ial 2 REHAU Inc 2004 REHAU PEX Plumbing Systems Technical Manual 855620 Leesburg VA REHAUs Techn cal Manual out nes a deta ed des gn procedure for s ng a p umb ng d str but on system Th s procedure is most l ke y to be used by p umb ng des gn eng neers or fa y soph st cated trade contractors for larger more comp cated projects It is not l ke y to be used by the major ty of resident Appendix C rESourCES plumbing contractors or builders The procedure described here could be used to develop a more straightforward and userfriendly tool that would identify the optimum distribution system design for a given situation 3 Uponor Wirsbo Inc 1993 Aquapex Professional Plumbing Installation Guide Apple Valley MN Wirsbos installation guide gives detailed instruction about installation of PEX tubing and manifolds instructions for various types of connections and required supports and recommended distances from heat sources such as flues or recessed light fixtures The guide does show the different options for system design including homerun remote manifolds modified homerun and runandbranch systems General advantages and limitations of the different systems are identified The guidance remains general except for a reference to a distance of approximately 12 to 15 feet from a central manifold as the maximum recommended for a homerun layout Demand or timed recirculation is also mentioned as an energy and water saving design feature Wirsbo provides a detailed design and installation guide for their Dmand Hot Water Delivery System 4 Vanguard Piping Systems Inc 2005 Manabloc Modular Manifold Plumbing System for Use with Vanguard Vanex SDR9 CrossLinked Polyethylene Tubing McPherson KS This manual offers general design guidance for parallel distribution systems using crosslinked polyethylene tubing However it does not provide sufficiently specific information to allow a contractor to size and lay out a distribution system for an entire project Examples of the type of guidance given include Typical supply line size per number of bathrooms Typical distribution line size per fixture flow requirement Use of multiple manifolds when the home is large or there are a large number of fixtures Understandably the Manabloc manufacturer does not discuss advantages and disadvantages of a parallel vs tree distribution systems under different circumstances 5 Viega North America Pure Flow Water Systems Installation Manual Bedford MA The manual provides detailed instructions for the installation of their Pexcel and FostaPEX tubing They outline different design and layout strategies in a general manner The manual also gives pressure drop information for their materials that could be used to develop more specific design tools 6 Zurn Industries Inc PEX Plumbing Design and Application Guide Zurn Industries Inc Erie PA The Zurn Guide offers similar installation instructions to the other manufacturers Each manufacturer recommends their specific crimp tool and gauge In addition to guidance regarding thermal expansion protection from damage pressure drop and flow rate the Zurn manual also discusses sizing and 112 112 112 Appendix C rESourCES 113 l i i l ll ipi i i i il i l i i i i i ibl it ti i i i ll i l i ocat ng man fo ds for para el p ng d str but on systems Wh e deferr ng to loca code requ rements Zurn does recommend us ng 3 8 nch tub ng for hot water l nes whenever poss e to reduce wa me stat ng that 3 8 nch tub ng is usua y adequate for most s nk lavatory and shower fixtures un ess the d stance is greater than 80 feet Appendix C rESourCES Plastics Pipe Institute PPI Technical Notes 1 TN17 Feb 1998 Crosslinked Polyethylene PEX Tubing This technical note provides general information on crosslinked polyethylene PEX such as What is PEX and How does PEX improve properties of PE Three methods of cross linking polyethylene to form PEX qualification standards and certification requirement are presented Finally several applications for the use of PEX piping and advantages of PEX pipe systems are listed 2 TN26 2002 Erosion Study on Brass Insert Fittings Used in PEX Piping Systems The objective of this test program was to subject different brass insert fittings and different pipe diameters for PEX plumbing systems to flow rates that represented the maximums that could occur if a plumbing system was sized according to the 2000 Uniform Plumbing Code Enough chlorinated water flowed through the pipe and fittings equivalent to 40 years of service in a typical single family residence None of the brass fittings failed during the test Weight losses were less than 3 percent for all fittings A test procedure is appended to this Technical Note 3 TN31 2004 Differences between PEX and PB Piping Systems for Potable Water Applications Several features and properties of PEX pipe are presented to differentiate between PEX and PB Mechanical fittings are tested and certified to comply with higher standards for chlorine resistance and longterm durability than were used for polybutylene pipe 4 TN32 2004 UV Labeling Guidelines for PEX Pipes These guidelines present recommendations for exposure and storage of PEX piping and an example of a cautionary label to be applied to packaging to ensure that PEX is not over exposed to sunlight UV radiation 5 TN33 2004 Standard Ultraviolet UV Radiation Exposure Method for Crosslinked Polyethylene PEX Tubing This is an industry consensus UV exposure test method that provides a definition of Total UV Energy per Monthly Time Period and requirements for PEX piping exposure Reporting and recording requirements are also presented 113 115 115 114 Appendix C rESourCES 114 114 114 115 G GLoSSArY ASTM American Society for Testing and Materials Corrosion deterioration in metals caused by oxidation or chemical action Crosslinked polyethylene a flexible thermoset plastic created using polymer technology where the molecules of a highdensity polyethylene HDPE base material are permanently linked to each other by a process called crosslinking PEX Elasticity a measure of material stiffness or the ability of the material to stretch or deform temporarily under a load Fitting a device or connection that allows the PEX pipe to change direction or size such as a tee elbow or coupling Fixture a device or appliance at the end of a water supply distribution pipe line Example lavatory water closet tubshower dishwasher Homerun a plumbing design that utilizes a central manifold and distribution piping to each hot and cold water fixture IAPMO International Association of Plumbing and Mechanical Officials ICC International Code Council IPC International Plumbing Code IRC International Residential Code Joint the connection of the PEX pipe to a fitting fixture or manifold Manifold a device having a series of ports that are used to connect distribution lines for several fixtures NSPC National Standard Plumbing Code 115 1 l i i l li i i l i i l li l i l l l i GLoSSArY Outlet see fixture pH a sca e rang ng from 0 to 14 that ranks how acid c or a ka ne a l quid is water w th a pH be ow 7 is considered acid c and water w th a pH above 7 is considered a ka ne Polybutylene a thermop ast c po ymer that was used for supp y water p umb ng from about 1978 to 1995 There were several reported failures therefore PB is no longer approved for water supply piping PB PPFA Plastic Pipe and Fittings Association PPI Plastics Pipe Institute Remote manifold a plumbing system that uses trunk lines from the water source to small manifolds at grouped fixtures such as a bathroom can be flowthrough or closed end Scaling process of mineral buildup on the interior of a pipe Test fixture the tubshower unit farthest from the water source that was instrumented to measure flow rate flowing pressure and mixed water temperature in the lab tests Thermoplastic having the property of becoming soft when heated and hard when cooled Thermoset having the property of becoming permanently hard and rigid when heated or cured Trunk and branch a plumbing design that has a large main line that feeds smaller pipes to each fixture Ultraviolet high energy light waves found in sunlight that lead to the degradation of many plastics and materials UV UPC Uniform Plumbing Code Wait time the time it takes for hot water to be delivered to the Test Fixture delivery time Water hammer a banging noise heard in a water pipe following an abrupt alteration of the flow with resultant pressure surges 116 No text in the image No text in the image