pex or cpvc

[frank]

I have a rental property that will be empty for about a month in nov. and was thinking about changing the cpvc plumbing that is now there to pex. I was wondering if any of you had any experience with pex and any pros or cons for the cpvc vs pex. the cpvc that was installed in 1989 when the house was built seems to develop a lot of leaks at the joints and I read a lot of comments on the internet that the cause of this would be heat expansion in the hot water heater or improperly glued fittings and thought I might get rid of some of the problems by changing to pex.

 

[Senator]

I have used both. If the CPVC is working, leave it. If you just have a couple of bad joints, it may be easier to just replace those. I have not had a problem with either one leaking, but maybe the initial installer did not do the joints correctly.

Be sure to clean, and cement both sides of CPVC.

If it was all to be replaced, use Pex. I use cinch clamps, as the install tool is cheaper, does all sizes (1/2 & 3/4), and is smaller to get into tighter spots.

If you use Pex, buy the 10' straight pieces, it is easier to work with and looks better when complete. Its about the same price.

 

[ChiliPepr]

I agree with Senator... except I bought the 100' red and blue rolls when I did my place... Every sink/toilet in the house has a home run to the basement. Much easier to work with then pvc or copper.

 

[Papa bear]

I'm 100% behind pex. To the comment above with the home run to every water source, this is actually one of the complaints, especially with homes with long distance from source to faucet.

The complaints come from the time it takes to heat the hot water for multiple uses, such as a shower and sink. With traditional plumbing, the hot water is in the line to the bathroom. With pex, you have to run the sink until the cold runs it's way through since it has it's own separate line.

I've only installed one house with pex, and I installed as a home run to each faucet. However, I don't see why you can't just run a home run to each bathroom and T off from there, thus mitigating the complaints.

I've installed cpvc on a home as well. It was easy to use, but I have since learned that there is potential for failure at the 25-30 year mark. Guess I've got another 15 years of good plumbing then!

In your case, with a rental, spot fix your problem with cpvc. Don't replumb the entire house if you don't have to.

 

[frank]

senator: did you have any leaks with the cinch clamps? I see the tool for that is just a pinch tool of some kind. the local plumbing inspector says either kind of clamp will work on the pex, but what kind of luck did you have? I was just inspecting the plumbing this morning and it only looks like a couple of places where it is developing some kind of corrosion before and behind the joints. I don't know if this is because of improper installation or bad adhesive. funny think is all the corrosion is in the hot water side. anyone know where to get instructions on how to properly install/repair cpvc.. I have read some info on the internet and some say use primer, others say not necessary. some say you have to bevel the pipe where you cut it off, kind of confusing.

 

[Car-Guy]

I've used both and really haven't had many problems with either. For me nothing is faster, cheaper and easier than PVC/CPVC. From what I've read and experienced, PEX is stronger, more flexible and more expensive overall. I do think if I were building a new house, I'd go with PEX. I'm not sure I would replace any CPVC in an existing house unless it started having problems. YMMV

 

[ChiliPepr]

I've only installed one house with pex, and I installed as a home run to each faucet. However, I don't see why you can't just run a home run to each bathroom and T off from there, thus mitigating the complaints.

All depends on the pressure.... If you run multiple lines you don't have the same drop in pressure when you turn the sink on with someone in the shower. Two lines can deliver more water than one line with a split at the end.

 

[pb4uski]

When we rebuilt in 2011 we used pex, as we had for an earlier remodel and had home runs from a manifold to all fixture. The hot water has only been an issue at our kitchen sink as it is a longer run from the HW heater to the manifold and then back to the kitchen. The other two bathrooms are close to the manifold so it is less of an issue.

If working with PVC/CPVC I would take the little extra time to use both the primer and the glue.

 

[Senator]

senator: did you have any leaks with the cinch clamps?

anyone know where to get instructions on how to properly install/repair cpvc.. .

I have never had a leak with the cinch clamps.

To repair CPVC, just cut the pipe with a hack saw, and replace the coupler, T or joint. You will lneed a new coupler and all the parts in-between.

You absolutely have to use a primer. Then a CPVC glue, not a PVC glue. There is a difference/ CPVC is for hot water, PVC is just for cold, like drains. Prime both sides of all connections. Glue both sides too.

some say you have to bevel the pipe where you cut it off, kind of confusing.

No bevel, just trim off all of the rough edges. A hack saw will give you that. Easy peasy.