Depending on state to state codes makes a difference whether or not PEX is allowed … having said that, the PEX will outlast copper but rats and mice have been known to bite and chew on the lines. CPVC is good but has a tendency to expand and shrink in extreme weather.
I had done a side job where the home owner had done a lot of research and decided on PEX after the job was done I heard through a friend of mine he had gotten his home appraised and found his house had depreciated $12,000 in value and said it wouldn’t have done that if he went with copper.
There are pros and cons to all of them. PEX is quickly becoming the goto material for residential work and renovations. It is easy to assemble and can be run in tight spaces due to its inherent flexibility. It can often survive freezing and thawing, unlike copper and CPVC. Like CPVC, PEX is resistant to poor water and soil conditions that can impact copper negatively. Some people report a plastic taste to the water, at least initially after it is installed. Some people are concerned about any plastics and possible health risks, although there is no conclusive information about any dangers associated with PEX or CPVC in regards to health.
Copper avoids these concerns and is a naturally antimicrobial material, but is almost 6 times the cost, not to mention the increased installation cost due to the extra work involved to install it. Copper can be prone to pinhole leaks due to bad water quality and even poor manufacturing techniques. So durability under certain conditions can be questionable.
CPVC is cheaper, but also takes more effort to install than PEX, and does not eliminate the health concerns like copper. It becomes very brittle of time and can be damaged by freezing. The only significant advantage is cost. CPVC is my least favorite of the 3. I use a combination of PEX and copper in my own homes.
I have 25 years experience as a MA Plumber. I can tell you I have used all three. I prefer copper, it’s been around for a long time, and I like it.
