Pex

[Greenman]

I've always been a fan of copper plumbing, but the project I'm doing now almost has to be done in pex. Is there a specific brand I should be looking at? It occurs to me that the fittings are far more important than the pipe, specifically the connection method.

Right off hand I can say that sharkbite is out. They may be the greatest invention since sliced bread, but at this point they fall into the "last resort" category for me. I'm interested in products with a long history of proven performance, and top notch quality.

 

[boomerang]

Never used it but from what I've seen on the telly, I think you'd want to use the crimp on type connectors that require the crimp tool. Sharkbites are for homeowners has always been my impression.

A bit off topic but I hope this stuff has been researched out correctly and that it will truly last over the long haul. My stepson and his wife bought a townhouse in Virginia that was done with the first generation plastic pipe and connectors. Sorry, I don't recall the name of the stuff. The connectors would start leaking after about x number of years. Less than 10 iirc. They came home one day to the ceiling in the DR sagging down over two feet, it being full of water. There was a slew of plumbing contractors that had sprung up to correct these issues which necessitated replacing every pipe and fitting in the house. We had showed up for a visit after the work was done and the drywall had yet to be patched up. These guys cut precision holes in the drywall and then fed pipe as needed, etc. They had these particular townhouses down to a science, knowing exactly where to cut, etc. Two story townhouses built on slabs which complicated the job. Anyway, just a story.

 

[drnickriviera]

I use the Uponor expander pex. That's what all the plumbers used in the area I was in and was the only brand the supply house stocked. I'm using the smaller of the Milwaukee tools. Can't say i'm too impressed now they they are made in china, it has been in for warranty repairs twice.

System has some advantages and disadvantages
Pex-a is supposed to be more expensive than b or c (crimp), but i'm no pro plumber doing tons of jobs so it doesn't matter to me
You need slack to make the connections, like a pvc glue joint. You can't assemble and do your crimps in place
Connections are fast, cut pipe flush, slip on ring, expand for 5-10s depending on pipe size, press on to barb, hold for a couple secs for it to shrink back. done, ready for pressure.
The tool is pretty small, I can take it under crawl spaces and use it between small stud/joist bays and not have to take a bulky crimper. Although i imagine they have something better (ratcheting?) than the large ones they have at the box stores.
Can be used in hydronic and fire sprinkler applications.

 

[Greenman]

Never used it but from what I've seen on the telly, I think you'd want to use the crimp on type connectors that require the crimp tool. Sharkbites are for homeowners has always been my impression.

A bit off topic but I hope this stuff has been researched out correctly and that it will truly last over the long haul. My stepson and his wife bought a townhouse in Virginia that was done with the first generation plastic pipe and connectors. Sorry, I don't recall the name of the stuff. The connectors would start leaking after about x number of years. Less than 10 iirc. They came home one day to the ceiling in the DR sagging down over two feet, it being full of water. There was a slew of plumbing contractors that had sprung up to correct these issues which necessitated replacing every pipe and fitting in the house. We had showed up for a visit after the work was done and the drywall had yet to be patched up. These guys cut precision holes in the drywall and then fed pipe as needed, etc. They had these particular townhouses down to a science, knowing exactly where to cut, etc. Two story townhouses built on slabs which complicated the job. Anyway, just a story.

This is exactly why I'm an extremely conservative builder. Every year there all sorts of wiz bang new products out that are supposed to "revolutionize" some aspect of construction, and every year there are near as many new lawsuits over past revolutionary developments. I don't like new stuff, I like proven, time tested materials and methods that get the job done.
I don't have issues with new technology that's easily replaceable, but fundamental components have to be proven in the field, not a laboratory.

 

[Greenman]

I use the Uponor expander pex. That's what all the plumbers used in the area I was in and was the only brand the supply house stocked. I'm using the smaller of the Milwaukee tools. Can't say i'm too impressed now they they are made in china, it has been in for warranty repairs twice.

System has some advantages and disadvantages
Pex-a is supposed to be more expensive than b or c (crimp), but i'm no pro plumber doing tons of jobs so it doesn't matter to me
You need slack to make the connections, like a pvc glue joint. You can't assemble and do your crimps in place
Connections are fast, cut pipe flush, slip on ring, expand for 5-10s depending on pipe size, press on to barb, hold for a couple secs for it to shrink back. done, ready for pressure.
The tool is pretty small, I can take it under crawl spaces and use it between small stud/joist bays and not have to take a bulky crimper. Although i imagine they have something better (ratcheting?) than the large ones they have at the box stores.
Can be used in hydronic and fire sprinkler applications.

The Uponor system always seemed to be superior to me, as it's a "natural" compression system (for lack of a better term). No one around here sells it though, it's all compression with metal bands. It sucks when you need a fitting and can't get it for 3 days. I may go that rout anyway, just because I'm more comfortable with it.

The way this house is laid out, I'll be able to access every connection with just a small hole in the drywall should it become necessary.

 

[zardthebuilder]

my house had blue poly. i had a leak right outside of the timeframe of the settlement. bummer. last year, a plumber convinced me to install a piece of pex. i have no idea what type. one month later, the fitting failed. good thing i caught it before it flooded my basement. the plumber quickly repaired the minor damage. now, it's back to copper. sample size of one is not very scientific, but i'm sticking with copper from now on.

 

[Greenman]

my house had blue poly. i had a leak right outside of the timeframe of the settlement. bummer. last year, a plumber convinced me to install a piece of pex. i have no idea what type. one month later, the fitting failed. good thing i caught it before it flooded my basement. the plumber quickly repaired the minor damage. now, it's back to copper. sample size of one is not very scientific, but i'm sticking with copper from now on.

Copper is hard to beat. The problem is that on the project I'm doing now, there would be hundreds of fittings involved.

 

[Zorba]

I used to be a big copper fan, but I've converted over to Pex now. My in-laws and my best friend's parents started getting a lot of slab leaks with their copper pipes (~40 year old piping). My in-laws lost three pipes in three weeks then decided to replumb their entire house in Pex. Copper is susceptible to erosion and corrosion over time.

Also being on a slab it is nice not having any fittings under the slab. If you have to replumb a house on a slab, you can run it all over the walls/attic without a ton fittings.

I know they've been using Pex in Wichita since at least 2005 and I haven't heard of any issues (I work with a lot of people that just relocated from Wichita).

 

[Kaido]

Does anyone know what the code would be of PEX inside of CPVC? I'd like to build a home at some point & I've had a good experience with Sharkbite & PEX for my own projects. Despite being expensive, it'd be cool to do all of the water lines in blue & red PEX with Sharkbite fittings myself. Ideally, I'd like to run CPVC as conduit, and then run the PEX inside of them - that way, if the PEX were to burst, it'd flow out into a room rather than in the walls or foundation or attic (then just have a simple floor drain in each room with water - kitchen, bathrooms, laundry room, etc.).

Sounds a bit nutty, but (1) that'd let me do all of the work & maintenance myself, and (2) that would protect me from flooding throughout the life of the house. I had a coworker who had a semi-custom built a year or so ago; his kitchen pipe burst and he came home to six feet of water in his basement, totally destroyed everything. I'd like that to NEVER happen...not sure what the rules are on PEX & conduit though.

 

[Kaido]

I use the Uponor expander pex. That's what all the plumbers used in the area I was in and was the only brand the supply house stocked. I'm using the smaller of the Milwaukee tools. Can't say i'm too impressed now they they are made in china, it has been in for warranty repairs twice.

System has some advantages and disadvantages
Pex-a is supposed to be more expensive than b or c (crimp), but i'm no pro plumber doing tons of jobs so it doesn't matter to me
You need slack to make the connections, like a pvc glue joint. You can't assemble and do your crimps in place
Connections are fast, cut pipe flush, slip on ring, expand for 5-10s depending on pipe size, press on to barb, hold for a couple secs for it to shrink back. done, ready for pressure.
The tool is pretty small, I can take it under crawl spaces and use it between small stud/joist bays and not have to take a bulky crimper. Although i imagine they have something better (ratcheting?) than the large ones they have at the box stores.
Can be used in hydronic and fire sprinkler applications.

I like PEX myself, but Flowguard has a pretty interesting comparison sheet:

https://www.lubrizol.com/CPVC/Documents/Sell-Sheets/FlowGuard-Gold-vs-PEX.pdf

 

[Greenman]

I used to be a big copper fan, but I've converted over to Pex now. My in-laws and my best friend's parents started getting a lot of slab leaks with their copper pipes (~40 year old piping). My in-laws lost three pipes in three weeks then decided to replumb their entire house in Pex. Copper is susceptible to erosion and corrosion over time.

Also being on a slab it is nice not having any fittings under the slab. If you have to replumb a house on a slab, you can run it all over the walls/attic without a ton fittings.

I know they've been using Pex in Wichita since at least 2005 and I haven't heard of any issues (I work with a lot of people that just relocated from Wichita).

Copper in a slab is a bad idea. Though with that said I've seen 50 year old instillations that have never had a problem. I don't like any plumbing in concrete, but sometimes you have to do it.
Around here copper is the standard everything else is measured against. Water from East Bay MUD is the best in the country, so we never get pin hole leaks or other water quality issues.

 

[Greenman]

I like PEX myself, but Flowguard has a pretty interesting comparison sheet:

https://www.lubrizol.com/CPVC/Documents/Sell-Sheets/FlowGuard-Gold-vs-PEX.pdf

I'd never be able to get my clients to accept CPVC, pex is a tough sell as it is.

 

[waffleironhead]

Never used it but from what I've seen on the telly, I think you'd want to use the crimp on type connectors that require the crimp tool. Sharkbites are for homeowners has always been my impression.

A bit off topic but I hope this stuff has been researched out correctly and that it will truly last over the long haul. My stepson and his wife bought a townhouse in Virginia that was done with the first generation plastic pipe and connectors. Sorry, I don't recall the name of the stuff. The connectors would start leaking after about x number of years. Less than 10 iirc. They came home one day to the ceiling in the DR sagging down over two feet, it being full of water. There was a slew of plumbing contractors that had sprung up to correct these issues which necessitated replacing every pipe and fitting in the house. We had showed up for a visit after the work was done and the drywall had yet to be patched up. These guys cut precision holes in the drywall and then fed pipe as needed, etc. They had these particular townhouses down to a science, knowing exactly where to cut, etc. Two story townhouses built on slabs which complicated the job. Anyway, just a story.

Im guessing that house was run with PB pipe. Polybutylene pipe failure is a nightmare.

 

[pcgeek11]

I'd never be able to get my clients to accept CPVC, pex is a tough sell as it is.

What is wrong with CPVC?

I had copper pipe and started sprouting pinhole leaks everywhere ( pipe in attic, house on a raised slab ). Copper isn't always the best, I will never buy a house with copper again. After the 6th water leak I said screw it. Delta Mechanical came in and re-piped the entire house in two days with CPVC. Very few holes in the walls and they patched every one to perfection. The best $2,400 I have ever spent. 10 years later and no more leaks.

http://www.deltamechanical.com/single-family-home-repipe/#

 

[pcgeek11]

Im guessing that house was run with PB pipe. Polybutylene pipe failure is a nightmare.

Agreed. I have a friend that had that in his house. Not only does it leak it splits and really floods the house quickly.

 

[Greenman]

What is wrong with CPVC?

I had copper pipe and started sprouting pinhole leaks everywhere ( pipe in attic, house on a raised slab ). Copper isn't always the best, I will never buy a house with copper again. After the 6th water leak I said screw it. Delta Mechanical came in and re-piped the entire house in two days with CPVC. Very few holes in the walls and they patched every one to perfection. The best $2,400 I have ever spent. 10 years later and no more leaks.

http://www.deltamechanical.com/single-family-home-repipe/#

I didn't say anything was wrong with it, I've never used it. What I said was I'd never get my clients to buy it. The majority of them see plastic and think "cheap". They expect water supply to be copper. They want to see shiny copper pipe in the walls, not white plastic. It's a tough sell.

 

[drnickriviera]

I like PEX myself, but Flowguard has a pretty interesting comparison sheet:

https://www.lubrizol.com/CPVC/Documents/Sell-Sheets/FlowGuard-Gold-vs-PEX.pdf

Frankly I think some of that is marketing bunk. I don't buy the reduced flow, where a you have to use an elbow for cpvc, you can use a bend support on pex. a 6" radius continuous piece of pipe is going to flow a heck of a lot more than a 90. Not to mention being able to use a manifold system on pex. That will greatly reduce the time for hot water to get to the fixtures

It could be just the brand, but i've done repairs on 30 year old cpvc. The stuff is brittle. I try to cut it out with my ratcheting cutter and it just shatters. I was trying to cut out a piece that froze and went back 3-4" from where it broke. Not only did it not cut cleanly, but a hairline crack shot back 6" further into the pipe. Don't know if it's the age or poor quality pipe, but i've run into it a half dozen times on my rentals.

I don't think there is any perfect solution. Each system has some disadvantages.

 

[Kaido]

Agreed. I have a friend that had that in his house. Not only does it leak it splits and really floods the house quickly.

See, that's why I'd like to run PEX inside of CPVC conduit, and then have floor drains in all of the water rooms...completely remove the chance for a pipe burst to ever ruin your home (plus it'd make mopping easier, just push all of the water into the main drain!).

I don't know what the code or feasibility of that idea is, but it seems like a great idea to me: in the even that a PEX pipe DOES burst, then the water drains into the larger CPVC pipe rather than into the wall, then into the pipe outlet in either the utility room (with a floor drain) or a house room (kitchen, bathroom, laundry room, also with floor drains). Then it'd be easy to re-pipe in minutes (run some PEX & clamp some Sharkbite). Plus, you could tie in some additional intelligence for auto-stop valves using water leak detection:

https://www.plumbingsupply.com/floodstopsystems.html

Seems like a really easy way to prevent your home from ever flooding (provided you're doing new construction). It'd double the installation cost, but be good insurance down the road if & when the original pipes fail. Plus, they have some pretty nice-looking drains available now (like from Kerdi) so you don't just have to have a giant hole with a grate in the middle of your kitchen.

 

[Scarpozzi]

Here's what I know about Pex. Sharkbite is actually a brand name. The push on connectors are sometimes known as Sharkbite connectors, but Apollo makes them too.

Pex can bend, but still needs 90 degree elbows to help alleviate tension in the line when turning sharp corners. Wide corners are fine, but in most construction, space is an issue. They make brass and plastic/nylon type elbows/wyes, valves, etc... The brass ones cost double, but are supposed to be no better (according to the guys I've spoken to...maybe they're more reusable if you ever pull the rings off a fitting....but most people would never do that.

There are 2 kinds of crimp bands. You can get copper ones that go around the pipe and compress. (soft metal, crimps more permanent) You can get steel ones that crimp and can be removed with a removal tool. The copper method is the preferred method by me. You can use a tool to measure the width of the fitting and test the crimp to make sure it's compressed enough. The tools are interchangeable between Apollo and Sharkbite. Multi-crimp tools are about $65 to do 1/2" and 3/4".

Finally, pex pipe has two key numbers to be aware of. The temp rating and PSI are important. The pipe can and will fail at high temps or high pressure ratings. The higher either number travels, the less temp or PSI it can handle. So be aware that it is possible to have a blowout if you're using it for high temp/pressure. Pouring a concrete slab around it is ok if you use an oxygen barrier pex. Otherwise, I would sheath it in PVC or conduit, which would also allow you to replace the line at a later date if you must.

 

[Kaido]

I don't think there is any perfect solution. Each system has some disadvantages.

Yup, that's it exactly. That's why I like the idea of PEX inside of CPVC, coupled with some per-room floor drains & an auto-stop valve for flood detection. My buddy helped me out with his Sharkbite kit when the pipe to my washing machine burst a year or so ago, we were done in no time! Maintenance would be so convenient down the road, and an in-wall burst pipe would be a breeze to deal with...the auto-stop valve would shut it off, and the in-floor drain would handle water routing, so all you'd have to do is swing by Home Depot, pick up some PEX, and use your Sharkbite connectors to do a quick fix.

 

[Booty]

Yup, that's it exactly. That's why I like the idea of PEX inside of CPVC, coupled with some per-room floor drains & an auto-stop valve for flood detection. My buddy helped me out with his Sharkbite kit when the pipe to my washing machine burst a year or so ago, we were done in no time! Maintenance would be so convenient down the road, and an in-wall burst pipe would be a breeze to deal with...the auto-stop valve would shut it off, and the in-floor drain would handle water routing, so all you'd have to do is swing by Home Depot, pick up some PEX, and use your Sharkbite connectors to do a quick fix.

Your idea makes sense to me. I might steal it when I redo our bathrooms. We're lucky in that our house happens to have pretty much all the plumbing running through the same walls - upstairs bathroom and kitchen are back to back and downstairs bathroom is directly under. So I could get by with running the PVC 'conduit' for the lines... and in places where they're horizontal I can create access panels in the backs of cabinets or behind shower walls (one shower shares a wall with the pantry, the other a mudroom, so having a random panel/door won't be an eyesore).

In terms of code - are you currently allowed to run a copper supply line inside CPVC if you want to? Anyone know? If it's not explicitly called out one way or the other, what's the issue? Wouldn't pass inspection I'm assuming?

 

[Zorba]

Yup, that's it exactly. That's why I like the idea of PEX inside of CPVC, coupled with some per-room floor drains & an auto-stop valve for flood detection. My buddy helped me out with his Sharkbite kit when the pipe to my washing machine burst a year or so ago, we were done in no time! Maintenance would be so convenient down the road, and an in-wall burst pipe would be a breeze to deal with...the auto-stop valve would shut it off, and the in-floor drain would handle water routing, so all you'd have to do is swing by Home Depot, pick up some PEX, and use your Sharkbite connectors to do a quick fix.

I think it would be a lot easier and cheaper to try to find some kind of hydraulic fuse for your house that would pop after more than X amount of water flowed through without stopping. We use them on aircraft hydraulic systems all the time, I am sure someone makes one that would work for a house.

I would think running the pex inside the CPVC would be very hard around corners, etc where you'd have to get the pex elbow inside the CPVC elbow.

 

[Zorba]

Copper in a slab is a bad idea. Though with that said I've seen 50 year old instillations that have never had a problem. I don't like any plumbing in concrete, but sometimes you have to do it.
Around here copper is the standard everything else is measured against. Water from East Bay MUD is the best in the country, so we never get pin hole leaks or other water quality issues.

Yeah, everything here is under slab. My in-laws are on well-water, which can erode copper lines faster than normal. Not sure what happened to my friend's parent's house, the slab may have shifted or it may have been something else.

 

[Kaido]

I think it would be a lot easier and cheaper to try to find some kind of hydraulic fuse for your house that would pop after more than X amount of water flowed through without stopping. We use them on aircraft hydraulic systems all the time, I am sure someone makes one that would work for a house.

I would think running the pex inside the CPVC would be very hard around corners, etc where you'd have to get the pex elbow inside the CPVC elbow.

Yeah, I was thinking about that - if the elbows could be put into CVPC screw-on elbows in the attic, then you'd have easy access for bends & maintenance access. Or even a simple access panel with a metal box that then gravity-feeds the water to the CPVC pipes in the event of a flood, that would be a fairly OOTB solution without much customization required.

I've actually had a couple friends whose homes have been completely ruined by bad pipes, so it's definitely a concern that has been on my mind. It's a non-standard design, however, so I'm wondering if there are any special roadblocks technically or code-related preventing people from doing it (outside of the economic hit for the additional materials & labor).

 

[Kaido]

In terms of code - are you currently allowed to run a copper supply line inside CPVC if you want to? Anyone know? If it's not explicitly called out one way or the other, what's the issue? Wouldn't pass inspection I'm assuming?

It looks like the terminology we're looking for is "sleeving":

http://www.inspectionnews.net/home_...-water-main-into-polyvinyl-chloride-pipe.html

This post in particular:

I sleeve PEX and schedule 80 PVC waterlines in schedule 40 PVC all of the time, especially when it runs underneath a concrete or asphalt driveway, porch, rockery or planter box.

A continuous 4" schedule 40 sleeve is cheap insurance against abrasions from backfill or other unforeseen factors -- And if the budget is padded enough, we'll run a second chase as an auxiliary/future.

Which actually came in handy earlier this week -- We've had some pretty fierce winds over the last few weeks, fierce enough to rock 200+ year old Douglas fir trees -- The rocking raised and broke the first 4" chase which sheered off the 2" schedule 80 waterline inside on a job we did back in 1999.

Fortunately, a camera sent down the auxiliary chase showed it to be undamaged -- So we dug up the waterline where it ran parallel to the driveway and fished a 20 foot length of 2" straight PEX through the auxiliary chase and reconnected it at both ends.

We were in and out in 6 hours and all of the digging was done by the homeowners landscapers, which saved them a bundle in labor and ensured that all of the landscaping was placed exactly where it was before the excavation.

Cheap insurance for sure. Plus easy maintenance & upgrades down the road!