PEX hot-water heat piping?
 

Is that stuff code-legal in NJ or even safe for radiant heat piping? Looked at a property up for auction today that was plumbed with 100% crimped PEX, at least in the basement and ground floor.(*)

Personally, I hate the stuff -- much rather pay extra for copper plumbing and whip out a blowtorch. Crimped connections seem skeevy to me, and will the stuff hold up to the nearly boiling water going to the baseboard radiators?

(*) - looked about 80% renovated and halfway decently: just that the flipper bought it for 2x current value in 2008 and got burnt.

The stuff is common today I believe. Although normal pex is not code for in floor radiant heating anywhere I suspect. The swaged on terminations when done with a good crimper seem to not be troublesome over the shorter haul so far anyways.

I have heard of them letting go before but assumed they were not installed properly.

pretty much all the plumbers around here anyway have gone pex.if you are using it in the floor as in poured right in the concrete you need an oxygen barrier pex.

Still NOT common in NJ -- most houses use copper. Thankfully the crap is still 100% illegal in NYC, at least for water supply and heating. A building code that forces quality if expensive construction is a giant plus in my book.

The PEX is not in the floor -- it just feeds baseboard radiators.

I still pretty much use copper as well. Most if not all local pro plumbers have drifted away from copper for domestic work locally.

Do not use chinese copper pipe. It may be better currently but it was junk.

If the pex feeders are all accessable I would not see this as a deal breaker especially even if not code.

I was watching Rehab Addict this weekend, and she plumbed in a smaller replacement boiler with it because she didn't want the possibility of the house being broken into and having the copper stolen. It's allowed per code in MN, I'm assuming, because it was on the show.

I know...don't believe everything you see on television.

I would be comfortable with the PEX as long as it was carrying an antifreeze solution. The combination of freeze, expansion and crimps makes me pucker up.

I have PEX in an RV, I like it for that.

All the (wet) underfloor heating systems that I've seen for sale over here are plastic now. The future's bright the future's plastic.

Submerged in concrete I would be concerned about the expansion/contraction issues with metals in concrete. Or the differances of the co efficients of expansion between the dissimular materials if you wish. I think the plastics used for in floor heating may have some metal flakes added as well to increase heat transfer.

They are not that cheap and I really do not quite understand the function of an oxygen barrier but it is a requirement of in floor systems plastics. Although years ago people got by with just dropping softer black plastic in and those systems are stll functioning.

I have two runs of a grey type flexable plastic in my own garage floor that I installed at least thirty years ago. There have been no issues so far with it. Today I would use some code type material though. In floor radiant heat is desirable from my perspective where possible and practical. I find that I am warmer up to my waistline or if I have to get down on the concrete floor it is also nice and warm.

Up until now I would not use a coupling device if it was to be burried in concrete. My son in law informed me this year that they now have an expensive german coupling that is gauranteed never to leak. This includes the cost of ripping up the concrete to find and repair it if it does. Not cheap though I suspect.

For the first time I have a very long in the home feed from a well pipe feeder enterance to the primary plumbing cluster to install. I will put in 3/4 plastic pex type simply because it is far cheaper. It is also a cold water feed so I expect no issues. I have run across rigid white older plastic tubing used in plumbing before and just do not like it myself. I think it was found to be somewhat problamatic on hot water feeds.

whats the big deal? makes for a great plumbing solution that does not suffer from the typical corrosion and interior pitting issues that things like copper do, and its way easier to repair when and if it splits like if the pipe freezes.

ive installed it for hot and cold water. It also expands a little better than copper, so in a situation where a copper pipe will split, a PEX pipe might split. interesting they used if for radiant heat, any pics?

Still think that burying water supply pipes in indoor concrete slabs is a stupid idea. My friend in Phoenix had a slab leak -- made a hell of a mess to fix even if her home warranty covered the cost. Why not plumb ground floor fixtures through the ground floor ceiling and run the pipes down? Either that or run the pipes in insulated channels cut into the top surface of the slab (i.e. you just need to remove the floating floor to get at them).

Most of NJ is a hard-water area, so corrosion of copper is a non-issue. If it splits due to freezing, you have other problems -- that should never arise :)

As far as ease of repair, I feel more comfortable making a good solder joint than a good crimp and can do it pretty quickly.

I've used it a bit. Does make me a bit squeamish. It occasionally has some attractive applications. In a big house we did in Berkeley, the owner wanted a small sink in the back of his detached garage. There was already a 2x4 assembly going from the house to the garage at about 7' high - spanned over a gate between the two into the back yard - it was used to conceal electrical conduit taking power to the garage. We just ran some PEX from the washer machine valves (closet piping) through the pony wall over to the gate, up and over and threaded through the exposed framing in the garage, still up high to avoid any accidental damage in future and then down the sink. Took about 1/10the the time that copper would have. Of course this is Mediterranean climate B-town.

We drained the sink into a space between the garage and the next house, about a foot wide, earth - a quart or two now and then won't hurt.

Same house we use PEX for radiant floor - buried in gyp-crete upstairs and attached under the hardwood floor on the main floor. No problems 15 years later except a few leaks at the registers.

I still lean to copper for most things though.

We did some radiant floor projects about fifteen years ago. I believe at that time the tubing to use was polyethelyne. The trick was no joints under the floor.

As the son of a master plumber, I used to cringe at Pex. But, it works well and is usually a better conduit for fluids than copper. I still think it takes the craftmanship out of the equation however. Current house is Pex'd and the only issue I have had was failure of a non Pex vacum breaker failing.