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PEX Design Guide - Second Edition

Design Guide: Residential PEX Water Supply Plumbing Systems (Second Edition)

In light of the popularity and practicality of the first edition of the PEX Design Guide in 2008, PPI and Home Innovation Research Labs published and released this second edition in November 2013. This edition includes many updates to reflect the increased usage of PEX systems in a variety of residential applications like water reuse and retrofit applications. New information has been added to almost every chapter including: standards updates in Chapter 3; updates to all applicable national plumbing, mechanical, and building codes in Chapter 4 including new green construction codes; updates to fitting systems in Chapter 5; and new design information on fixture flow rates and water hammer in Chapter 8. There have been many changes to national green building standards over the past few years. Many of those changes are captured throughout the document. In addition to the many updates, we are pleased to note the participation of third party certification bodies in the creation of this guide. It is believed that this new level of cooperation will make this guide easier to use and provide more value to installers and inspectors alike.

This Design Guide provides the information and resources necessary to design and install cross-linked 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 fire sprinkler systems, and to 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.