Replies

1. 
   marv | Jun 09, 2004 07:01pm | #1

   I'm not a plumber, but I do books for a plumber here in town and his is super busy doing new construction.  He is doing almost all pex in new construction and also does radiant floor heat as a specialty.   Unless homeonwer specifies copper and is willing to pay more, he installs pex.

   Pex will not burst when frosen (if you use the correct copplings) and will not pick up minerals from the water like copper will.

   You get out of life what you put into it......minus taxes.

   Marv

2. 
   GoldenWreckedAngle | Jun 09, 2004 08:17pm | #2

   The new PEX is significantly improved over the old stuff, which is all I have any real experience with. Given my experience with the old PEX and its problems I still feel more comfortable with copper in my specs. Of course, I still use tar paper instead of Tyvek too.

   That said, I don't know anyone with the new PEX in their home that wishes they had gone copper.

   Kevin Halliburton

   "Do you see a man skilled in his work? He will serve before kings; he will not serve before obscure men." - Solomon

1. 
   BillHartmann | Jun 09, 2004 09:00pm | #4

   "Given my experience with the old PEX and its problems I still feel more comfortable with copper in my specs."

   What OLD PEX?

   Or are you thing of polybutle (sp?)?

3. 
   csnow | Jun 09, 2004 08:35pm | #3

   One downside to PEX is that it is not 'self-supporting' for long horizontal runs.

   The 'homerun' systems that are often touted will not work well with a hot water recirc scheme.

   There is also a possibility that it may support a bio-film layer, but this may only be an issue with stagnant runs.  Studies underway.

   PEX breaks down under UV exposure.

   If you have acidic water, PEX is certainly the way to go.

   Installation should be lower with PEX overall.

4. 
   MojoMan | Jun 09, 2004 09:36pm | #5

   My plumber, while not old, is very conservative. He just tooled up for PEX and is very enthusiastic. The ability to snake the pipe much like wire greatly increases installation speed.  The ability to color-code pipes is kinda cool. The tools are expensive. I don't know the brand, but he uses a system that crimps a black copper ring on the joints after a brass fitting has been inserted inside the PEX.

   Al Mollitor, Sharon MA

5. 
   Mongo | Jun 09, 2004 10:02pm | #6

   PEX is an accepted way to go.

   There are a variety of companies marketing tubing, off the top of my head the most commonly available are Wirsbo, Rehau, Kitec. It's all about advertising when it comes to name recognition...as well as what type of tubing they sell.

   For tubing, PEX is generally crosslinkied via one of three methods...PEX-a, PEX-b, and PEX-c. Some methods are better than others. Ask before you order. Generally, PEX-a (or engel) is consdered the best and most completely cross-linked, PEX-b (silane) is the worst, or the least cross-linked. PEX-c is similar to -a in quality, but again, -a is, in general, the most common PEX out there.

   Wirsbo and Rehau are both a good product. Kitec is as awell, but it's slightly different...it has a layer of aluminum sandwiched between two walls of PEX. Thus it holds a radius and doesn;t sag as much as others.

   Vanguard is a brand often mentioned on the internet, don't give it a second look.

   For an open domestic water system you don't neccessarily need an oxygen barrier.

   Kevin made a good point regarding a circulatinig loop. Tought to do if you homerun every run. Easier if you install a mini-manifold at each use location (kitchen, bath, laundry, etc) and feed that mini-manifold with a homerun froma main manifold in the basement.

   "Homerun" means a continuus run of tubing...no unions, joints, etc.

   I prefer to run continuus runs through framing bays. No unions or connectors buried in framing bays, etc.

   PEX can withstand freezing...but you dont want to exploit that. Each time a location freezes/expands, it does supposedly become slightly weaker in the area that was frozen.

   If the tubing kinks on you, support the tubing and use a heat gun to heat the kinked area until it is translucent. Then let it cool to opaque, and it's as good as new.

   Tooling is expensive, but you can sometimes find used tools for sale at a plumbing supply house or on eBay. Buy, use, then resell them yourself.

   Realize that the tools are often manufacturer-specific. Meaning Brand A's stuff can't ber mixed with Brand B's stuff.

1. 
   NickNukeEm | Jun 09, 2004 10:16pm | #7

   Had some insurance repair work this spring on a house whose heating system is made up of Pex.  The Pex tubing strapped to an exterior stud on a perpendicular interior wall froze and burst.  The break point was at the location where a cable run penetrated the stud.  I figure a cold draft whistling through the stud was the culprit, and foamed the stud before closing it up. 

   I was surprised, as I did some heating troubleshooting for a couple last year with a Pex system, which had froze on them the previous year.  No breaks.  Different Pex, maybe?

   I never met a tool I didn't like!

1. 
   Mongo | Jun 09, 2004 10:27pm | #8

   It certainly could be different PEX...or it could have undergone so many freeze/thaw cycles it just finally tired out.

   Another reason to avoid wet plumbing at exterior walls.

   One other thing. I think it was csnow that mentioned UV degradation. PEX should be kept boxed until used, UV does cause it to become more brittle.

6. 
   glatt | Jun 09, 2004 10:28pm | #9

   I'm in the same situation.  In my reading, the one thing that worries me the most is the breaking down under UV light.  It is something you want to keep in mind.  If you are running the PEX tubing near a window in an unfinished basement, you may want to put insulation on it to keep the light off it.  Otherwise, you may find in five years that it is breaking down and prone to cracking.

   Also, make sure you buy tubing that has been stored inside, out of direct sunlight.  Store yours the same way.

1. 
   Nuke | Mar 20, 2005 02:22am | #10

   Is Pex any more susceptible to UV-induced breakdown than PVC? Are not modern windows with UV-blocking coatings? Sounds like a winning combination.

1. 
   dIrishInMe | Mar 20, 2005 04:54am | #11

   If I caught your drift about windows, personally, I don't think I'd trust the low E glass to remove all of the harmfull rays.  Anyway, take a look at this link;

   http://www.ppfahome.org/pex/faqpex.html

    Matt

1. 
   Nuke | Mar 20, 2005 03:47pm | #14

   Ok, I get the UV importance to the PEX product. Still, how does one know the amount of UV in an unfinished basement with no window treatment for long-term concerns? Heck, I put up miniblinds on the basement windows just to keep direct sunlight out and thinking of putting inexpensive UV-blocking tinting on those windows. Would not this combination be adequate until the basement is finished?

1. 
   dIrishInMe | Mar 20, 2005 06:28pm | #15

   I think you are correct, and doubt that the sun would shine directly on plumbing in a basement for a long period each day - unless maybe it was roughed if for a yet to be finished project...  I think the intent of the whole thing is to say that PEX can't be used outside.  If anyone was concerned about the basement application, it would seem that the pipe insulation idea would be a 10 minute fix. Matt

7. 
   slimjim | Mar 20, 2005 01:54pm | #12

   I borrowed the crimp tools from a buddy for my second floor laundry room. The chase they had to go up was super small. I ran both lines up from the basement in about 5 minutes! You save so much time that its worth buying the tool if you are doing any sizable work. Unlike copper, you can fish it to a degree.

   The supply house here stocks Vanguard. At least from them, the potable pex is slightly less easier to work with than the heating variety-maybe cause it's not as crosslinked? 

   But then, we've been using the Mr. Pex for radiant, which you can bend so much easier than the Wirsbo types. Stuff's awesome.

   Also, if you do run it, buy an uncoiler. They really help a ton.

1. 
   averagejoe | Mar 20, 2005 03:36pm | #13

   I just did my first pex install out of neccessity. I had to get a hot water line to a bathroom I was installing for a friend of mine. He had put a sleeve over a finished basement space at the time it was being finished between the hot water heater and the new bathroom area. The problem was there was no way to get long copper pipes manuvered up into it! I had seen the Kitec system at a hardware store in Canada a few years back and decided that here was the perfect situation to give it a try.

   The run went from a Tee off the hot water heater line, up and over some air ducts, into a joist bay accross the finshed space, turned down into a small soffit run, up and over a beam, back into a different joist bay, and then down a stud wall. I then had to pull a supply line for the toilet through a similiar path. Wow! It was almost as easy as pulling wire. Half an hour and my "rough-in" was done. Even without the access issue into the sleeve, that would have been 4-5 hours with copper, with lots of cuts, elbows, and temporary blast shielding while I attempted to solder in some tight spots in the framing.

   I was really impressed with the product. The pipe itself (as someone mentioned before) is actually to layers of pex with an aluminum layer sandwiched between. This probably made it a little more difficult to pull, but it held its' shape very well and needed very little support because it was relatively rigid. The fittings were all compression type and so the only tool needed was crescent wrench.

   Any guess what I'm using next time I have some plumbing to do?