I am running new plumbing lines in the basement of a 3-unit apartment building that I own. The purpose of the re-plumbing is to separate out the water service for each unit. All of the existing plumbing is copper. The hot and cold copper lines that go to each individual apartment are easily accessible in the basement, so separating out the water service for each apartment will be easy because all I will need to do is tie into the copper lines for each apartment in the ceiling of the basement.
I don't want to use copper, and I think I am probably not going to go with PEX. My plan right now is to use CPVC pipe and fittings for all of the new plumbing and to tie that into the existing copper lines for each apartment.
One question I have is whether to use all CPVC, or use CPVC for the hot water lines and PVC for the cold water lines. My inclination is to use all CPVC rather than try to save a few bucks on materials by using PVC for the cold water lines. Does that make sense? Is there any reason NOT to just use all CPVC instead of trying to use both CPVC and PVC, other than the cost of materials?
I also have questions about how to connect the CPVC to the existing copper lines. I can easily solder female threaded adapters to the ends of the existing copper lines and use male threaded CPVC adapters to make the connections. But, I think there may be a problem with doing that for hot water connections due to possible variations in expansion of the two materials and, therefore, possible future leaks at the connections. I have seen the Sharkbite and Watts push-on connection adapters but they make me nervous in terms of how secure the connections would be. And, I believe there are copper to CPVC adapters that either screw onto, or get soldered to (I am not sure about that), the copper and then are glued to the CPVC pipe.
I would appreciate any thoughts or suggestions on how to best make the connections from the CPVC to the existing copper.
And, any thoughts, suggestions, pointers etc. regarding the whole CPVC (or CPVC and PVC) project would also be appreciated.
Thanks.