What pipe is used for a home's water lines: PEX, PVC or CPVC?

PEX (cross-linked polyethylene) is now the most common choice for water lines inside new homes; HUD reports it reached 63 percent of single-family construction in 2016. It resists corrosion and scale, costs less than copper, and its flexibility helps it survive freezing without bursting. CPVC handles both hot and cold water, while standard PVC is limited to cold water uses such as buried irrigation lines. Not every plastic pipe is approved for every use, so the type, rating and fittings must match your local plumbing code and the manufacturer's listing. A licensed plumber or inspector can confirm what is allowed.

Check your local rule. This varies by state, county or city. Your permitting office has the final word; the official lookup pages below show you who that is.

Sources

• Water Piping in the HomeU.S. Department of Housing and Urban Development, PD&R Edge
• CPVC Pipe and TubingPlastics Pipe Institute
• Landscape Irrigation Equipment Part 8: PipingClemson Cooperative Extension