PEX Plumbing for home system

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Wooden Head

Burning Hunk
Hearth Supporter
Sep 14, 2009
249
West Michigan
I saw a thread where they are talking about using Pex in place of copper. Just looking for some guidance for using pex and what tools and fittings do you like?
 
Are you plumbing a new home, add-on, or rework? I only work in copper, so no help either way, but this will better shape the answers you get from others.
 
I've done some PEX, in renovation work, not new construction.
I had misgivings, but i'm liking it, having screwed together steel, glued PVC, and sweated copper in the past. It is by far the easiest.
Get the crimp tool. Around here, $50-$60 iirc, mine does 1/2" and 3/4". Use the solid copper rings (they are blackened) that it crimps, and use the brass fittings. The research I did showed this was the best way to go. The tube cutter is good to have as well, it's cheap.
There is a prep tool that bevels and preps ends, not expensive, but not necessary unless you are using the sharkbite push fittings. Sharkbites are way more expensive, but even faster, and can be disconnected and reconnected. I have a couple of those in use, where the PEX meets copper or steel. There is a ring removal tool, I didn't get one, was just extra careful about not needing to redo any.

There are pinch tight compression rings, and they use a plier type tool. It relies on bent metal to stay tight, as opposed to the crimp ring which is swaged down. I didn't feel comfortable putting that behind walls.
 
I have the Uponor Pro Pex system installed on parts of heating system. The selection of systems 15 years ago were far less than today. A friend had heating and plumbing business and had great success and no failures. There are no crimp rings. I initially borrowed the expensive at the time expanding tool and eventually bought a set. All you do is prep the end of the tube, slide a backing ring over the tube and then expand the tube with the tool. The place where folks can screw up on is the tool has to be rotated 1/4 turn as the tube is expanded, otherside the tool can leave a groove inside the tube. Then just slide the expanded tube over the fitting and its on for good. No issues with wet or dripping pipes. I must admit I do not have it on the piping near my boiler as in certain circumstances I could exceed the 200 deg F max temp rating.

They have a lot of systems for different fluids. The intriguing one is they make a residential sprinkler system that uses the domestic cold water tubing for distribution.

Just like copper a drywall screw will go through it so metal shields are needed on 2x4s. It may self seal initially around the screw tip.
 
Lots of action in the Sharkbite fittings these days . They are easy to install and require almost no tools but are so very expensive to use in quantity. I generally use regular pex and crimping rings ,but the sharkbite comes in handy in tight places where you cant get the crimper in. I do feel the regular PEX is more reliable however iv never had a failure in the sharkbite fittings. In the pex iv had just one piece of domestic hot water line split and develop a leak. I still have all my old copper fittings, pipes and the tools to install them ,just dont use em much anymore.
 
Pex is so easy to work with. you can rent the tools from your local tool place or get them from your local plumbing store. Don't cheap out if you buy them and the cutters are a must for clean cuts. Get yourself a tool that is made for close areas as at some point you will have a spot the normal crimp will not work without alot of cursing. If possible go to a store that deals in nothing but plumbing. We have a andrew sherit here and the price of the fittings is less than 1/2 of the local canadian tire or home hardware huge savings if your doing a large job..
Sharkbites are a great thing to use in a really tight area or to retrofit from copper to pex especially if your living in a older trailer. i use these quite a bit and never had a failure. You dont need a special tool to remove just use a adjustable wrench or a wrench the same size as the pipe and push the collar back and they come right off
 
I've worked extensively with PVC, CPVC, copper, and PEX.
My thoughts.
Pex benefits:
  • easy to work with
  • fast
  • inexpensive
  • no glues
  • it is a bit flexible so minerals don't adhere well and it is less prone to breakage when frozen (anecdotal observation)
  • its flexibility is useful for avoiding fittings on sweeping turns -- especially if you're using the coiled stock
  • (Edit per Peakbagger's response below) no flame needed, no fire potential
Potential problems:
  • MIce may chew through it to get water (reportedly)
  • It degrades in direct sunlight
  • The coiled stock is sometimes difficult to straighten and work with on longer runs.
  • Brass fittings can fail if exposed to ammonia from rotting organic matter or other exposure (dezincification).
I like the SS pinch clamps better than the copper rings because:
  • Stainless steel is much stronger than copper and more corrosion resistant. (860 versus 210 MPa ultimate tensile strength) That said, copper doesn't corrode that fast either but still...
  • The crimping tool fits better in tight spots which has been a big plus many times
  • One crimping tool fits most if not all.
  • They're easily removed without having to resort to cutting
  • Widely available at big boxes - not so the copper clamps in our area though they used to carry them.
  • As an auto mechanic for 15 years I never once saw one of the SS clamps fail and was impressed by how hard they were to cut off. They are widely used on medium pressure hydraulic and fuel hoses and other places.
I'll only use a sharkbite quick fitting in a pinch. They're expensive and I don't like to rely upon some elastomer seal in a slip fit for the long-term.
I use the PEX brass fittings and wouldn't use the plastic fittings. That said, I've already seen at least one brass fitting failure (perforation) but attribute it to a factory defect.
 
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For some reason over here we are not allowed to use the SS pinch clamps anymore. against code
 
When I was doing plumbing in my house a few years ago, I thought of using pex but the amount of work was so small, it was cheaper to keep going with copper.

One thing I did notice, is some of the pex sizes had smaller inside diameter than the copper pipe of the same size. Something to consider if that matters to you.
 
Copper sucks, rots, is an expensive relic for people with more money than sense. Like Bronze armor and weapons, in the silicon age.

I've re-plumbed almost my entire house with pex from the big box stores. The copper was paper thin and springing pinhole leaks inside the walls and ceilings.

Used sharkbite when easier, copper rings when possible. Pros buy both the straight lengths and coils, and use them according to the application.

Wish I'd gone wit the stainless crimping system.
 
When I was doing plumbing in my house a few years ago, I thought of using pex but the amount of work was so small, it was cheaper to keep going with copper.

One thing I did notice, is some of the pex sizes had smaller inside diameter than the copper pipe of the same size. Something to consider if that matters to you.
One thing to remember is pex is perfectly smooth inside copper is not. So their will be less resistance in pex

Sent from my SM-G950W using Tapatalk
 
It has been used for some time by all the builders here. Cost drives it. Hope it doesn't end up with the issues they had with PVC used for domestic water lines years ago.
 
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Copper sucks, rots, is an expensive relic for people with more money than sense.
...or those old enough to have been thru a few of these fads. Remember butylene piping? PVC supply side piping? In a world where building materials change ever decade, it’s amazing how long copper has held on, while many newer systems and come, failed, and gone. I hope PEX is the (next) final answer, but suspect it’s every bit as likely we’ll be studying newly-discovered cancers created by its wide deployment in DHW systems, 20 years from now.
 
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...or those old enough to have been thru a few of these fads. Remember butylene piping? PVC supply side piping? In a world where building materials change ever decade, it’s amazing how long copper has held on, while many newer systems and come, failed, and gone. I hope PEX is the (next) final answer, but suspect it’s every bit as likely we’ll be studying newly-discovered cancers created by its wide deployment in DHW systems, 20 years from now.
I insist on BPA-free pex. ;-)

I think we should worry way more about those phenols in your whiskey and beer than the water.

I put all my drinking water at home through a carbon filter, and I've been suffering from copper pipes my whole life. I'm a late adopter generally, but I'm willing to take a shot at this fad.

Plus I can't solder.
 
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I insist on BPA-free pex. ;-)

I think we should worry way more about those phenols in your whiskey and beer than the water.

I put all my drinking water at home through a carbon filter, and I've been suffering from copper pipes my whole life. I'm a late adopter generally, but I'm willing to take a shot at this fad.

Plus I can't solder.
I really don't have a strong feeling, one way or the other. I grew up sweating copper pipes, my grandfather and great-grandfather owned and ran a plumbing business, and my dad was forever renovating old buildings. So, I'm quick and comfortable with copper, and I've never had any of the issues I've seen from folks who live in areas with acid water and improper electrical grounding.

.... and you leave my whiskey alone! I'm enjoying an Old Fashioned right now. :-)
 
...or those old enough to have been thru a few of these fads. Remember butylene piping? PVC supply side piping? In a world where building materials change ever decade, it’s amazing how long copper has held on, while many newer systems and come, failed, and gone. I hope PEX is the (next) final answer, but suspect it’s every bit as likely we’ll be studying newly-discovered cancers created by its wide deployment in DHW systems, 20 years from now.
Pex has been used for a long time in Europe with no problems before it came here. I just redid our whole house by myself in a weekend. No way I could do that with copper. And now I have a manifold which reduces pressure drop when using more than one fixture
 
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Pex is awesome! When I replumbed the cabin I did it exclusively with pex due to the ability to withstand freezes. I still pitched the lines to drain though.

We redid a friend's cabin and his froze. All was well.

When I ran heating lines up to the attic I was finishing off I ran pex lines with an O2 barriermade for heating systems.

As I have to replace the mix of copper and galvanized in my house I generally use pex with copper rings for most of it, then stub on with a sharkbite.

I can sweat, do pvc, screw stuff together, etc, but when I can do pex, I do.
 
Oh, leftover lengths of blue, red, and white pex make great light sabres for kids who like star wars.
 
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i have used pex on remodels and on the new project that we are using. when I did the work myself, I was using the crimp rings and everything went pretty well. I got a removal tool, as there were a few times when I put on temporary fittings, etc.

The new project was all done by a plumber, but we ran an 1.25" pex line for our new water line and sprinkler line. They also insulated lines and buried them under the floor prior to pouring the concrete to run to my peninsula and my washer. The sprinklers all feed off of the cold water, as to the rest of the fixtures.
[Hearth.com] PEX Plumbing for home system


they used Wirsbo Pex and connectors which seem a bit more solid, and copper stub outs.
[Hearth.com] PEX Plumbing for home system
 
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I got a removal tool, as there were a few times when I put on temporary fittings, etc.
Actually, this would be a huge advantage for the DIY'er. The ability to temporarily stitch the system together so the family can get showers in the middle of a weekend-long re-plumbing job, should not be under-rated.
 
Keep in mind, lead solder used for sweating copper fittings on potable water for many years is a source of long term lead poisoning in older homes.

The big advantage to me is heat is not needed to make the joint. It happens frequently, usually on older construction, that fires are started by plumbers torches. I run into on commercial construction all the time, that if a torch needs to be lit there has to be a paid fire watch during and for several hours afterwards. Most of my new commericial jobs use pex on the small stuff, thinwall Propress on the intermediate sizes and Victaulic grooved piping on the big stuff. Victaulic just recently came out with a grooved system that handles low pressure steam. The fittings are usually more expensive but skilled labor is far less and most of the systems have built in quality control marks and stops to assure that the joints are made up correctly.
 
Actually, this would be a huge advantage for the DIY'er. The ability to temporarily stitch the system together so the family can get showers in the middle of a weekend-long re-plumbing job, should not be under-rated.
Totally agree, and an advantage I've taken numerous times, sometimes with comedic results.
On a recent weekend I found out how much water can flow out of a 1/2" PEX at 80 PSI after mistakenly closing the wrong supply circuit. Me, now soaking wet on a ladder trying to stem the flow while yelling for my wife before finally deciding to abandon the leak and go and shut off the main.

The heat issue that Peakbagger mentions reminds me of how much time I used to spend waiting for a line to drain before I could heat it for soldering. I was never crazy about the whole plugging the pipe with white bread trick. Who eats white bread anymore anyway?
 
I worked in the Midwest in "Americas Dairyland" early in my career at a papermill that used mostly thin wall stainless steel pipe. Most of the welders also did work for dairy farms which uses similar piping (but different fittings). When tigging thin wall stainless, the pipe is supposed to be backpurged with inert gas and the dairy guys used day old bread to plug the line. This was 3" to 12" pipe so they used a lot of bread.

I have been stymied plenty of times in my industrial career with a crew sitting around waiting to get at a line that was dripping so it could be welded. If the pipe was big enough we would sometimes have to weld a coupling on a low spot on in the direction the water was coming from. Once the coupling was welded on then they would blow a hole into the pipe through the coupling and let it drain while the flow hopefully stopped out of where we were trying to weld. When done they would screw a plug into the coupling. On the really big lines we sometimes had to resort to an inflatable pig stuffed up the line to block the flow.

By the way, for awhile there was a copper pipe joining system that used some sort of epoxy or polyurethane glue to glue copper pipes together. I think it used the same fittings.
 
Totally agree, and an advantage I've taken numerous times, sometimes with comedic results.
On a recent weekend I found out how much water can flow out of a 1/2" PEX at 80 PSI after mistakenly closing the wrong supply circuit. Me, now soaking wet on a ladder trying to stem the flow while yelling for my wife before finally deciding to abandon the leak and go and shut off the main.

The heat issue that Peakbagger mentions reminds me of how much time I used to spend waiting for a line to drain before I could heat it for soldering. I was never crazy about the whole plugging the pipe with white bread trick. Who eats white bread anymore anyway?

there is a reason I have a manifold of all my shutoff valves in one spot, in addition to at the fixtures:
[Hearth.com] PEX Plumbing for home system


I also have it set up so I have a shutoff above my hose connections, and a drain below, so I can shut them off and drain them if need be. This has come in handy a few times!