A. Master plumber Rex Cauldwell responds: Polyethylene pipe is not approved for in-house cold or hot water lines. According to the International Building Code, once the polyethylene service pipe enters the building, you must terminate it within 5 feet. Whether you consider the crawlspace part of the building is up to you and the inspector.
The intent of the code is to prevent the poly pipe from being used for the in-house water lines. If you use polyethylene pipe to go directly to a water pressure tank without any take-offs to fixtures — or, for city water, to go straight to a main valve in the crawlspace — you are probably following the intent of the code, even if you have more...
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