PEX - Educate Me

[deckmonkey]

Pex is easier to use most of the time unless you have to add hangers or need it to stay straight. Anything that has to look half decent should be copper. It also breaks down in uv light, natural or artificial. I have had to change sections that were leaking over top of pot lights in a t-bar ceiling and exposed lines in commercial buildings. I wouldn't use sharkbite fittings unless you have no other option which is almost never. They can blow off and I know of more than a few times it has happened. Running pex to the tub spout can cause enough friction that water will drip out of the shower head when running the water.

 

[Jim greengo]

We still cant use pex in Omaha unless something has changed that I haven't heard about,the nasty cpvc **** is legal though for some reason.

 

[My Old Tools]

I can verify that rodents will chew through Pex.

 

[Toomanytools?]

Never used the stuff, always been a copper guy and I'm pretty good with it. I may be doing some small plumbing jobs, water not HVAC. Is there any advantage in trying pex? I know it's flexible and easier to run. I have everything I need to work copper and wouldn't want to invest in any more plumbing tools, I don't know if any are needed. Will I save any money or a significant amount of time or labor? I'm looking for opinions from people who have experience with both materials. Also, I have a few lengths of copper and a lot of fittings in stock. Sounds like I'm talking myself out of using PEX. Still would like to hear your opinions.

Not a plumber but I have done a lot of plumbing, I bought a Milwaukee M12 ProPEX Expansion Tool Kit on EBay very slightly used guy did like a kitchen remodel with it $250, new runs about $400. So using Pex A, and expander rings super easy and fast. I have talked with several plumbers and the biggest savings is labor with Pex, takes about 1/3rd the time as with copper. Some guys will still run copper at termination points like sinks and toilets, hose bibs, washer. Have you ever tried getting a 3/4" 10' piece of copper through the floor joists? It's near impossible, with Pex you can thread that through easy.

 

[Whitworth]

I've re-plumbed about 80 percent of my house with PEX, to replace the polybutyl piping it was built with. What I learned was you need both coiled and straight PEX. It is IMPOSSIBLE to straighten coiled PEX, it will always maintain a memory. That said, the natural curve in coiled stock can be taken advantage of for gentle bends, sharp bends are best done with a 90 fitting. The brass fittings are far and away the highest cost of the job (you'd think they were gold, not brass), the crimper and other tools are nothing by comparison. I had zero leaks in all connections with the PEX, compared to copper sweating there's always a joint or two that needs to be drained and re-soldered.
A short learning curve, as said using the crimper in close quarters sometimes needs some head scratching, but it sure beats holding a propane torch with one hand, solder with the other and all the while hoping you don't set fire to the house.

 

[acer66]

Does anyone have some experience with the newer plastic fittings?

 

[rlitman]

Does anyone have some experience with the newer plastic fittings?

The plastic is less likely to corrode if your water has issues that will leach zinc from the brass (it shouldn't, but if you have acidic well water for example), but it is thicker. Since the PEX OD remains the same, plastic fittings are more restrictive with a smaller ID than brass. For that reason, I use brass.

 

[mustangmike6996]

I just pulled a bunch of copper from my basement and ran PEX. I got the 100 foot roll of 3/4 and a 100 foot roll of 1/2. If I had to do it over, I would run the 3/4 in 10' straight sections. Trying to unwind and run it from the roll is almost a 2 person job. The 1/2" is really easy to use for branching from the manifold. I used the Otiker style pinch clamps (already had the tool)

You end up with a lot more fittings than you think. I used many more 90* fittings than I thought I would have to.

 

[acer66]

I use bend supports as much as I can instead of 90deg fittings.

 

[acer66]

The plastic is less likely to corrode if your water has issues that will leach zinc from the brass (it shouldn't, but if you have acidic well water for example), but it is thicker. Since the PEX OD remains the same, plastic fittings are more restrictive with a smaller ID than brass. For that reason, I use brass.

Thank you, brass it is.

 

[theoldwizard1]

Not a plumber but I have done a lot of plumbing, I bought a Milwaukee M12 ProPEX Expansion Tool Kit on EBay very slightly used guy did like a kitchen remodel with it $250, new runs about $400. So using Pex A, and expander rings super easy and fast.

I love the finished product, but the cost of even the hand tool and the PEX A is pretty steep to overcome for a DIY person.

My son and I re-plumbed his house. If I did that again, I would use the copper stub outs, especially in a bathroom. Much cleaner looking.

 

[alexb2000]

I used cheap 1" Pex, brass fittings, and copper crimp rings for my irrigation system up in the mountains of NM at 8,000'. I buried it about 6" down so it is well above the frost line. I ran about 2,000' to my orchard and other areas, it was easy to get in rolls from Amazon and delivered by UPS.

It has gone through 5 or 6 winters with sub-zero temperatures, water freezing in the pipes, rodents, elk, deer, bears, etc. Way more abuse than you will see in any residential setting. I also have it exposed to the extreme NM mountain UV where it comes up to connect to the hydrants.

ZERO problems. PVC and black poly pipe was a nightmare. It would take days every spring to try and repair all the damage to get a leak free system and even then more damage would appear over the growing season.

My neighbors though I was crazy to spend that much for irrigation, I guess their time is free because they are getting really good with a spade.

Just a quick report on durability.

 

[Rice5505]

SO after looking through this whole thread, i see a lot of back and fourth on PEX. I'll say this. Working at a 750M/yr union plumbing and piping company we run both for domestic water. the Milwaukee tools other mention work well (and we put them thing through the paces) copper will be neater and pex if strapped right can look OK. we buy it in 10'-0" sticks. most of the time. I would up size everything under 3/4" to 3/4" because the id on pex is smaller that copper (this depend of course on the amount of water pressure available) but it also help if you get calcium build up or other contaminants. One major advantage is that Domestic HW doesn't require insulation because the pex itself has an R value that meets national (and my home state KY plumbing code). one thing you might want to look at is victaulic HDPE or CU (grooved pipe and fittings) systems. youll pay a premium for the pipe and fitting, but the only tool required to install is a socket. Personally when installed correctly we've not had a problem with pex. when we have a choice we run copper, we run pro press (crimp). the primary issue with pex is its not rated for higher temp water so anything over 160 will degrade the pipe and shorten the life span and void the warranty. With residential application that may not be an issue for you if you keep your water heater adjusted correctly. Just my 2$ but if you already have everything to sweat copper (and its not radiant heat system as has been stated) run the CU. no sense in buying new tools unless you want to.

 

[59 wagon man]

all you guys who love pex may want to check out the military's latest housing crises. seems the pex piping installed less than 10 yrs old is leaking like crazy,Nibco just settled a $43,000,000nlawsuit about its pex pipe

 

[LS6 Tommy]

I've used Propress PEX fittings for a long time. The Propress blows away the manual crimp rings and compression fittings. They're a little more money, but save so much time on the job they pay for themselves.

Tommy

 

[coldh2o]

all you guys who love pex may want to check out the military's latest housing crises. seems the pex piping installed less than 10 yrs old is leaking like crazy,Nibco just settled a $43,000,000nlawsuit about its pex pipe

That's a Nibco issue, not PEX in general.

The Takata lawsuit is huge, it doesn't mean airbags are bad.

 

[coldh2o]

Back on topic, I used PEX for our new home build 9 years ago. Probably 30 home runs to a manifold, I think I used maybe 5 fittings in the whole system. 1/2 inch for all, haven't experienced any noticeable pressure loss, even with multiple fixtures running at once.

I also re-plumbed our cottage last year. Great stuff for a system that has to be winterized, much fewer problems with potential freezing damage.

I used copper crimp rings, never had to re-do one and no leaks, pressure tested to 150 psi. The crimping does get tricky in tight quarters.

 

[LS6 Tommy]

the primary issue with pex is its not rated for higher temp water so anything over 160 will degrade the pipe and shorten the life span and void the warranty. With residential application that may not be an issue for you if you keep your water heater adjusted correctly.

There is more than one type of PEX. I have never seen any PEX only rated for 160° F max. PEX has pressure & temp ratings printed right on it. There is also PEX made specifically for hydronic heat applications. I ran over 300' of it last Thursday and Friday.

Tommy

 

[jeepxj]

I'm partial to pex A expansion. Much better flow. No missed or partial crimps.

 

[6768rogues]

I have used both plastic and brass fittings with good results. I always put 100 lbs. of air in the piping to test it, and I leave it charged with air during wallboard installation. During construction, I check the air gauge occasionally to make sure everything is ok.