CPVC Pipes + Repairs to Mobile Homes

Friends -

I’m buying a lot of homes these days. I thought I had run into everything, but now I’ve (inadvertently) purchased a few homes with CPVC piping. My plumber suggests replacing the CPVC in the entire house ($1,500 - $2,000 expense). I think he is trustworthy, and he says the stuff is junk and if I don’t replace it, it’ll wind up costing me way more in ‘band-aid’ repairs over the next few years.

Has anyone else run into homes with CPVC? Should I replace it, or just patch it every time it breaks…?

Many thanks,


link. He may have been good intentioned but ill-informed. He may have been thinking of PB piping.

This was truly a troublemaker and caused leak problems.

This is what he has identified as your pipe:


This is the PB pipe which is grey, black or sometimes silver in color. It was manufactured in the 1970’s.


Hope this helps. Replace with PEX piping.


cpvc piping is not uncommon in mobile homes. It is problematic in that it breaks, splits and shatters easily if the pipes are exposed to freezing weather or the home sits unheated and un-winterized.

Once again (a la Tony Colella), it all depends on what you are doing with the home. If you are selling it for cash, make sure any pipes are repaired and there are no exposed pipes. If you are renting, I recommend replacing EVERYTHING with PEX (as does Don above). If you are selling on a note, you have to decide whether your buyers will keep up the heat and not leave any pipes exposed because if you get that home back it may be a disaster.

I bought a '93 DW in 2003 with cpvc and learned the hard way. I fixed 13 leaks before I learned my lesson.


Right On, Steve. However, I used that old nemesis word

I will never, ever, ever, ever, ever, ever allow repair cpvc again. I have a very long, painful exprience with cpvc that I have shared in the past but suffice it say that Dr. B is absolutely correct in his post.

I have learned the hard way that if you find one broken CPVC line under your home that is likely caused by freezing then there are dozens more. These pipes split under freezing conditions. Instead of just one spot breaking the entire stalk may split in one, hidden crack from fitting to fitting. I started out replacing that stalk, turned on the water and then found the next. This went on for days in terrible and cold conditions. I finally got it all fixed after essentially replumbing the entire double wide one split at a time but the worst part is that is now re-plumbed with … you got it… CPVC!

I only use PEX now with an occassional Schedule 40 PVC (not to be confused with CPVC) to act as a transition where the water comes out of the ground from the main line.

I can replumb an entire home for a few hundred dollars worth of PEX tubing and then fittings. I do the work myself. I buy the fittings at a plumbing supply store (I cried when I found out how much cheaper they are then lowes). Lowe’s and home depot charge almost $2 or more for some fitting where I can buy them for 1/4 of the price or more when buying in bulk at the plumbing supply store.

The PEX tool is expensive (about $135) but well worth it. DO NOT BUY THE PEX TOOLS AT HOME DEPOT OR LOWES! Those tools are too big to use in mobile homes. They are close to bolt cutters in size. You need to buy the smaller, hand sized ones for sale at the plumbing supply stores and online.

Even when I paid a professional handyman service some years ago to replumb a sinlgewide with PEX they charged about $1,200 and were done in about a day.

I now do it myself for less than half of that and I do it the way I want it done.

I have even replumbed some homes by moving all of the lines inside the home so that I would never have to crawl under the home again. I created a chase type box along the edge of the ceiling and wall and ran the main lines from one end of the home to the other (where water was needed) and then came off of that to supply toilets, baths and sinks. No one knows what in that box even if they notice it.

Now the tenant will immediately notice if a leak is occurring and I can stand in the warmth of the home to repair it instead of laying in a cold puddle under the home to repair it.

I also find that if the tenant has heat, I have no leaks!


…with you, Tony.

I interpreted Jefferson’s post as meaning: “OOPS, now here’s a real problem. This MH has CPVC pipes in it.”

I’m sure the drain lines are CPVC. That doesn’t make them bad. If the MH had not been hooked up to water for testing, that doesn’t make the water lines bad, either. Just suspect.

If home came from a temperate climate where freezing had not been a problem, the pipes do not deteriorate unless there had been excess exposure to UV. PEX will do the same thing. On the other hand, if the MH came from a climate subject to freezing, then I would certainly want to know it’s history.

To me the options would be:

(1.) Test and find out or (2.) Replace and be sure.

Granted, the repairs are cheaper and easier and can be a DIY project.

Additional info—

I had seen this some time back. Finally found it again.

Is PEX freeze-break resistant?


High Temp and Pressure linitations

What are temperature limitations for PEX?

PEX tubing can be used up to 200

Much as Tony and others have said, I simply replace all the lines with pex… biggest problem is making sure you get the hot and cold water hooked up correctly… tape on one of the lines makes sure you don’t have to go back and change a hook up.

A quick tip I’ve found is that the pex crimpers will work on both PB and CPVC, had a handyman about 18 months ago transfer cpvc to pex with a compression ring and coupling without my realization… Tenant was moving in before I realized it. I decided to leave it with the anticipation of replacing it at a later date, that date ain’t come yet.

I use this same strategy to deal with water line problems when it’s to freakin cold for me to be crawling under a home… slap a new section of pex in until it warms up. On copper I’ve found that high pressure fuel line and screw down clamps make a great bandaid until I get around to pexing the unit.

The biggest help for landlords that I’ve seen with pex is to install shutoff’s on everything… nothing is an emergency repair and as Tony said if you buy your fittings at a plumbing store instead of the big name home improvement stores you can do this on the cheap. It normally runs me about $200 to completely pex a home and about a day and it’s done!

Build your stub outs that go through the floor first and tape the hot water line on top and bottom so you know which is which and you only have to crawl under the home once to hook everything up. I’ve found it’s easier for me to install the lines under the home and use 1" heavy pipe wrap to insulate both pipes together. if the tenant ever has any freeze out problems I tell them to let the HOT water line drip a bit and it’s enough in my area to keep both lines running strong even on the coldest days.

This one tip on using PEX from Scott and Tony has saved me thousands of dollars over the years, we get the same quotes to pex a unit… $750-$1200 when I can do it for about $200 it’s a no brainer IMHO.

Best wishes,

Ryan Needler

Hey Ryan,

You can buy PEX in blue or red, that way you can keep your hot and cold straight.


Dr. B is correct and I do use Red Pex from time to time, especially if I am running lots of plumbing in a home. If I don’t have red pex on the truck I use white for everything and wrap the hot line in strips of red duct tape every so often.

I still prefer the red pipe, especially if each line is individually wrapped in tube style insulation. If you peak in you can immediately tell which is which when/if making a future repair.


“Much as Tony and others have said, I simply replace all the lines with pex… biggest problem is making sure you get the hot and cold water hooked up correctly… tape on one of the lines makes sure you don’t have to go back and change a hook up.”

You can buy colored PEX. It comes in red, blue & white for the same price. Easier than tape!

“A quick tip I’ve found is that the pex crimpers will work on both PB and CPVC”

I had no idea you could do that. I’ll definitely keep that in mind.

“On copper I’ve found that high pressure fuel line and screw down clamps”

You’re one of THOSE guys? I’ve bought a lot of your homes . . . . 1/2 the home is a conglomeration of fuel lines, garden hose & screw clamps!!

“use 1” heavy pipe wrap to insulate both pipes together. if the tenant ever has any freeze out problems I tell them to let the HOT water line drip a bit and it’s enough in my area to keep both lines running strong even on the coldest days."

That’s and EXCELLENT tip! Why hadn’t I thought of that?! Thanks, Ryan!

Hey Ryan,

Just a heads up to the landlord’s like us who enjoy section 8. Our local inspector has now made individual water cuttoffs mandatory (no real problem there other than the time and money to add these fittings).

One alternative he does allow for is a whole house cutoff inside the home. We usually install these near the washing machine hookup.

I just make one big loop from the main line to this cutoff in the utility room area and back down to the main line feeding the home. I have done some closer to the water heater, depending on the layout of the home.

I still think it is best to have the cutoff right under the sinks and toilet as this allows the tenant to shut off one fixture while allowing us to sleep in and fix it tomorrow.

As Ryan has seen, on all of our mobiles we pex it so that the exterior/main cutoff is accessible right next to the skirting and we mark it as such with permanent marker on the skirting. This way anyone who finds a leak can find out how to shut the water off.

Many of our homes had interior/individual cutoffs but I am finding that a surprising number do not.


"You’re one of THOSE guys? "

Yup sure am, I have this adversion to crawling under a home when it’s below about 60 degrees outside… I patch it and fix it come spring time… I HATE copper pipes and have slowly been changing them out between tenants while its warm. Pex has proven that it can freeze solid and still hold water, I love this stuff!!!

Tony, I have not done a section 8 move in for a few months now, but my understanding when they started talking about the individual water cutoffs was that it was a main cut off to each unit instead of just a master water meter to an apartment complex or the likes… Don’t bother me one way or the other, I look at shut offs as a cheap insurance policy that I won’t ever have to drop what I’m doing to go fix someone’s water.

I will vouch 100% for placing the main cutoff’s right near the outside of the home, I have one park that they installed the cutoff’s right smack in the middle of the MH pad and you have to crawl under the home to get to it… I’ve yet to be able to talk any of my tenants into crawling under a home to shut the water off… This was the park that 3 units froze at the same time last year! Every unit is getting the shut off moved to the outside as I replace plumbing.

This is a repair that I budget for when I make a purchase, I may not do it right off but it will need done for my piece of mind… For those of you that can’t ever see yourself crawling under a home this is an easy repair system that can be taught to basically anyone… if you have the tools you can take an $8/hr person and show them how to use it and given a day or 2 and they’ll have it down. it’s an easy way to drop replumbs from 1k+ to 3-400.

Best wishes,

Ryan Needler

The idea behind the section 8 enforcement is damaged caused to homes and tenant’s property due to leaks they cannot or will not shut off.

As you have written, most cutoffs are not well placed for easy access by tenants. I have always moved them to the edge of the skirting and marked this location as the cutoff.

I had run a main cutoff inside the home in some of my doublewides and as I understand it, many newer homes are coming with this as a standard feature.

If you are going to have to run a cutoff to the side of the home by the skirting, it may make more sense to save the cost of the fittings and just run it inside. It is nice to not have to go outside or mess with skirting in the cold to cut the water off and on.

Like you, I prefer to add the cutoffs on each line under the sinks etc. but this can add up due to the cost of the cutoffs and PEX to Poly fittings. I figure it runs about $8 per line or so. If you have mulitiple baths this can add up pretty quick (2 per fixture plus toilet).


Ryan, I do not like to crawl under the home when it gets below 20.

I have found running the water supply line inside a piece of insulated flexible duct. From the ground to above the belly wrap. Eliminates freezes even @ 5 degrees with 50 mph winds. I also use pex for everything. And sometimes run the pipes inside the home. I have even had those pipes freeze when the box covering them was not vented to allow heated air to circulate. So if you are in the north, cut holes in the box and cover them with plastic vent covers or soffit vents. I have a crimper that uses a vice grip as the leverage and does 3/8 1/2 3/4 for $40 it is available online. It’s great for tight spots.