Originally Posted by
Terry Beck
If I read the IRC-2006 correctly (and I believe prior editions as well), PVC is allowed as material for "water service pipe" (ASTM 1785) by P2904.4.2 but NOT in "Water Distribution pipe". (I'm in a discussion with a "certified plumber" who claims that where he is from, Florida, PVC is 'always' used for cold water distribution as long as CPVC is used for hot water. Personnally I think he is full of hot air).
Nope, not full of "hot air", full of Sh*T is more like it.
I understand the prohibition of use as supply pipe for hot water (sched 40 PVC is only rated for 140 psi at 73 degree), but can anyone explain why it is allowed for use as water service, but not allowed for use as distribution pipe for cold water?
Because it is not rated high enough for pressure and temperature and is formulated differently (being more susceptible to breaking and cracking - I think). So it is allowed "outside" the structure for pressure uses, i.e., water service pipe and sprinkler pipe, and "inside" the structure for atmospheric pressure applications, i.e., DWV uses.
In this case, the home is on a well where water pressure would only run about 30-55 psi at best.
IRC requires 40 psi minimum.
2nd question; not being a plumber, what color of cement is used for CPVC? His house had a vivid blue color staining around the joints (both PVC and CPVC), which I don't recall seeing before on CPVC. Does anyone know of any problems if the wrong cement is used?
That blue is the primer. It is blue so the inspectors will know: 1) primer was used, 2) the correct primer was used. I'm not sure that it is acceptable for CPVC, I'll have to go look at some in my garage and see what it says.