Pex - Al - Pex help please

My brother-in-law is attempting to install radiant floor heat in his new home.....he asked me (like I'd know) how he is supposed to bend the 1/2" pex-al-pex without it kinking in between his floor joists. He said that this stuff is really hard to bend and if you make too small of a 180 turn with it, it kinks. He's got this stuff wedged between the 16" on center floor joists for now, but really needs to get them on 8" centers...any ideas?

deerefanatic said:

A tubing bender should do the job.... After all, you're working with plastic-covered aluminum tube there.........

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You're serious?? Wow, didn't see that coming. I've never worked with the pex-al-pex before. I thought it was more like pex than metal tubing....hmmm....thanks for the info, I'll let him know.

free75degrees said:

I have never done any radiant floor heating, so this is just a total guess - could he skip every other row so that he has a larger turn radius and then when he gets to the end go back and do the rows that he skipped?

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He might have to do that...I'm going to stop up his place tonight and take a look at this stuff. I've never seen this before so it should be interesting. Considering how hard it will be to work with, it seems odd that he given this for wood floor heating...seems that a regular O2 barrier pex would have been much easier to install.

Thank Aiken and DaveBP for the links....I'm checking them out now. The Manual of Modern Hydronics has got some really good detail in it. The other site I haven't checked out yet.

deerefanatic said:

Huskurdu said:

deerefanatic said:

A tubing bender should do the job.... After all, you're working with plastic-covered aluminum tube there.........

Click to expand...

You're serious?? Wow, didn't see that coming. I've never worked with the pex-al-pex before. I thought it was more like pex than metal tubing....hmmm....thanks for the info, I'll let him know.

Click to expand...

Well, I won't say that it's stiff like metal, but it has metal in it and has memory when bent.... so a tubing bender would work well....

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I stopped up to his place last night. That stuff is quite different than I expected. We figured out how to route it so that he doesn't make any hard bends so he can live without the tubing bender, at least for now.
Is it 'normal' to use pex-al-pex for under (wood) floor radiant heat? It seems like a bit of overkill when the cheaper stuff would work just as well.