CPVC Pipe and Fittings

CPVC Pipe and Fittings

Chlorinated polyvinyl chloride, a semi-flexible pipe for indoor use, is commonly referred to as plastic pipe. It was the first non-metallic pipe to replace copper as a pipe material. It installs quickly and easily with CPVC glue or push-on fittings. It won’t dissolve like copper, but it will split faster than copper when subjected to freezing temperatures. It is not affected by acidic water which has a low ph, which will corrode metals.

CPVC male and female adapters

Because CPVC is a brittle plastic, adaptors with all plastic threads exhibit some weakness when paired with metal fittings. Male and female fittings tend to leak at the threads and both threads tend to crack at the shoulder when tightened. To avoid this, always insert a piece of pipe in the fitting as it is screwed into a fixture. To completely alleviate such problems, avoid all plastic threaded fittings. Instead use metal threaded CPVC male and female adapters.

CPVC Pipe and Fittings turning corners

As with other fittings, you can turn a corner at either 45 or 90 degrees with CPVC fittings. When installing a fitting on pipe, use a fitting with same size hubs on both ends. When connecting to another CPVC fitting, use a street elbow or street 45 degree fitting. These fittings have a hub on one end sized for pipe insertion and a smaller diameter hub on the other end, sized to slip into another fitting hub.

CPVC valves

There exist 3 types of CPVC in-line valves. The round handle valve is a globe valve and should be avoided. It slows down the water flow and does not conform to many local plumbing codes. A ball valve is the preferred valve. However, the metal valves designated for CPCV tend to leak around the handle and the all plastic models tend to jam or be hard to turn off. The best CPVC valves are female threaded ball valves with two CPVC brass male adapters and Sharkbite type push on valves.

CPVC Pipes and Fittings, Couplings, caps and reducers

You can connect CPVC pipe together with glued couplings. You can glue PVC to CPVC using a special white coupling. If you need a reducer coupling or don’t have one, you can glue a reducer bushing on a full sized coupling to create a reducer coupling. You can even put a reducer bushing or coupling on each side of a ¾” coupling to create a ½” coupling.



CPVC pipe and fittings drop ear elbows

CPVC drop ear elbows are used to terminate a CPVC pipe and start a threaded pipe. Use these for the through the wall pipe to the shower head any time you want to come through a wall with a finished pipe to a stop valve under the sink or toilet.

CPVC T fittings

CPVC T fittings are used to send water off to the sides of the main line, from a ¾” main line to a ½” line for the toilet or at the end of ¾” line from which you want to branch one or two ½” lines to various fixtures.

CPVC pipe and fittings unions

A CPVC union is used wherever you want a removable coupling, for example, at an appliance that might need to be replaced, like a water heater. It is very easy to avoid CPVC unions by simply cutting a pipe and gluing a coupling back into the line.


You can interface CPVC with PEX with a special fitting that glues onto CPVC and has PEX barbs on the opposite end. You can interface CPVC with copper or PEX using push on fittings. You can also interface CPVC or PEX with threaded galvanized fittings and nipples using male and female adapters.


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