CPVC to PEX for intermediate plumbing

[JD]

Ron - Cool looking fittings. Makes me want to try them when the occasion arises. I usually just go to a 1/2" adapter then to Pex. This would save a fitting.

Greg - There is sched 80 pvc and cpvc. They have the same nominal pipe size though. Sched 80 will have a smaller I.D.

[skipper386]

just wanna point out something about CPVC:

CPVC may not be used for Drain, Waste & Vent systems. Even if they could get the CPVC pipe in the proper sizes, there are no DWV rated CPVC fittings and the codes prohibit glueing dissimilar pipe and fittings together.

When plastic pipe is desired for the DWV system the choices are ABS pipe or Sched. 40 PVC (Some local jurisdictions will permit sched 30 PVC).
"But what exactly is CPVC?


To answer your question, CPVC is Chlorinated Poly-vinyl Chloride. You can think of this in terms of a second generation of PVC pipe inwhich the chemical formula of the pipe was altered slightly to overcome some of the problems that were associated to PVC pipe.

CPVC pipe is made in two dimension standards:
Although very seldom used, CPVC and fittings are available in the ASTM Pipe Schedule dimension standard, which means the pipe and fittings are exactly the same dimensions as thier PVC counterpart.

The CPVC most often used for residential plumbing systems is made to the ASTM "CTS" (Copper tubing Standard) and the physical dimensions of the material is the same as copper pipe.

Like everything else in this world CPVC has its good points and bad.

ON THE GOOD SIDE:
-CPVC is relatively inexpensive when compared to copper or PEX.

-CPVC is very user friendly for DIY repair and maintenace because it can be cut with a PVC snap cutter, hack saw, wood saw or a common piece of Nylon Masons twine when used as a wire saw.

-Joints are made using a simple primer and glue procedure that requires no specialized tools or training.

-Pipe and fittings are readily available in all hardware or home supply centers.

-PVC is impervious to the acids occassionally present in the water in some regions that might deteriorate copper pipe or fittings.

-Initial installation costs are usually much lower because the material cost is much less and it is not nearly as labor intensive as running copper.

-Under most plumbing codes CPVC is listed as approved for both supply (line from the municipal main or well source to the structure) and Distribution (Piping within the structure) and may be used both above and below grade without any additional wrapping, coatings or special protection.

ON THE DOWN SIDE:
-When compared to the alternatives (Galvanized iron pipe, Copper pipe & PEX) CPVC is the least durable and would have the shortest expected lifespan under normal circumstances. Having said that, it must be understood that while it may have the shortest life expectancy in the real world it would still provide 25 to 30years or more of service without major problems and in regions that have acidic water that would deteriate copper pipe and fittings CPVC would be a much better choice. (I realize that many will argue PEX is a better choice in areas with acidic water but in truth PEX systems all have copper stub outs and fittings that are subject to the same deteriation as copper pipe.)

-CPVC has a very high linear thermal expansion factor and when installing CPVC provisions must be made to allow for pipe movement under normal use.

-Of all the alternatives CPVC would offer the least resistance to damage resulting from pipes freezing.

-CPVC must be protected from direct sunlight or UV exposure.

-As it ages CPVC will become slightly brittle and must be protected from physical shock or damage.

-When burned, such as in a house fire, CPVC emits a deadly toxic fume.

-For reasons known only to rodents CPVC is highly subject to damage from rats, mice, squirrels and Opossums and may not be a good choice of materials for running under a structure with a crawl space or raised foundation, especially in rural areas.

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“Automatic simply means that you can't repair it yourself handyman adelaide.”

[JD]

And now you know. Excellent post Skipper and welcome to the forum.

JD

[mdnagel]

Hi folks, sorry for the delay in posting (been busy; plus, hadn't had the e-mail notifier set up on this thread [my mistake]).

The home is a 1998 Champion. Not sure of the model.

The pipes are all [C]PVC. They are color coded: red line for hot, blue for cold.

I had picked up some shark bite fittings (1/4 turn valves), but I decided not to use them, as I'm extremely leery of stuff that isn't either glued, soldered or screwed. I ended up tracking down some adapters- 3/8" compression x 1/2: MIP: http://www.homedepot.com/h_d1/N-5yc1v/R ... ogId=10053 (I removed the compression fitting- didn't need). Connected the new faucet lines to the 3/8" end of the connector and then took the existing hoses and connected them to the 1/2" end of the connector. Yeah, extra hoses and all, but it's working and I don't have to worry about looking over my shoulder... and, heaven forbid, if I had to I could install the old stuff.

Sigh, didn't achieve the necessary level of success with my latest plumbing job:

P1060509 (Small).JPG

Something like 48 connections, 42 glued (and behaving nicely). I'd (erroneously?) used pipe tape on all the threaded connections. No real way of tightening things, have to cut pipes!

[mdnagel]

Just to try and clarify a couple of things... It IS CPVC. And, it's all original, except, perhaps, for a braided line for the kitchen faucet (maybe from initial install [optional equipment] of dishwasher?).

As recently posted, I gave up on the notion of doing any hacking and was able to meet my requirements using an adapter.