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Discussion Starter · #1 ·
Down here they finally gave the go ahead to run pex under slab, use to be only roll copper. Saves on material for sure. Just about every HO on new builds are requesting PEX these days.
 

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Pex with no fitting allowed here under a slab.
 

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Discussion Starter · #3 ·
I thinking its been the norm up North for awhile it just finally passed down here. Like within the last year or so...
 

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I've got no problems running pex under -ground.Believe it or not,before I left Florida ,we were running cpvc under-ground in Pinellas county,which was legal [with fittings,not coiled].That to me is not a good idea,but we used to hydro-test to either 3 times the incoming pressure or 150 psi,not to exceed 150 psi.,crazy huh.So if you held that pressure for 24 hrs. like i used to, then you walk away pretty confident with the system.
 

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Discussion Starter · #5 ·
It makes sense for the PEX since copper has skyrocketed over the past couple of years.
 

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I get the feeling you just get way too much enjoyment out of posting your local requirements! LOL

But that's cool because like I said before, I really, really enjoy hearing about it.
Chicago's code is ridiculous in a lot of ways, but I also see why in a lot of ways. About a month ago a fireman in the suburbs was killed in a warehouse fire when a NH CI fitting fell from 40' and hit him in the head, the 6" wye broke his neck and killed him instantly. That is basically impossible with the hub and spigot joints that Chicago requires.
 

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Discussion Starter · #10 ·
Chicago's code is ridiculous in a lot of ways, but I also see why in a lot of ways. About a month ago a fireman in the suburbs was killed in a warehouse fire when a NH CI fitting fell from 40' and hit him in the head, the 6" wye broke his neck and killed him instantly. That is basically impossible with the hub and spigot joints that Chicago requires.
Dang thats horrible.... I can see why they enforce that kind of code then.
 

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Sorry to hear that. I guess wearing a hard hat was not a requirement.
 

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Miss read that post, sorry man. :bangin:
 

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I see no problems with PEX under a slab. Back when I was still doing houses, FmHA was requiring that all copper be in insulation. I liked that because it protected the pipe from grinding on coarse dirt. I should imagine that the same would be true of PEX - it would be a good idea to protect buried pipe with foam insulation up through the cement. If done well, it should even be possible to pull a new piece of pipe through it, maybe?

My biggest concern with PEX isn't the pipe - it's the thin brass fittings. So I don't think they should be buried. If the water isn't aggressive, it might not matter, but it's possible for the water to change over years, too. I could swear our water here is more aggressive than it used to be, based on seeing more pinholed copper.
 

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pex and concrete must get along pretty well. There's a ton of it in slabs for hydronic heating.
 

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I agree. That can be a problem no matter what the pipe material. Our problem with pex in IL is we have to oversize the pipe due to the restrictive fittings. I never have used the stuff other than hydronics where it just loops out and goes back to the other manifold.
 

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Our problem with pex in IL is we have to oversize the pipe due to the restrictive fittings.
To some extent, the concern over the restriction is over rated.

That said, the Uponor or Rehau fitting systems eliminate that issue and in my opinion, is a selling point.
 

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I see no problems with PEX under a slab. Back when I was still doing houses, FmHA was requiring that all copper be in insulation. I liked that because it protected the pipe from grinding on coarse dirt. I should imagine that the same would be true of PEX - it would be a good idea to protect buried pipe with foam insulation up through the cement. If done well, it should even be possible to pull a new piece of pipe through it, maybe?

My biggest concern with PEX isn't the pipe - it's the thin brass fittings. So I don't think they should be buried. If the water isn't aggressive, it might not matter, but it's possible for the water to change over years, too. I could swear our water here is more aggressive than it used to be, based on seeing more pinholed copper.

Uponor fittings are actually made of hard black plastic which are ideal for underground, but that said, why would you have any joints underground in the first place bend support and just tape them to your stubouts until the house is framed and ready to be roughed in after the underground is completed
 
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