PEX A or PAP for above floor panels

WillC

Hi,

The Modern Hydronic Heating book recommends to use PAP for any type of aluminum panel to avoid expansion sounds. The Roth panels I am looking to install says PEX A is fine and no adhesive is required.

What's the best technique? PAP, Glued PEX A or just PEX A?

How bad are the expansion sounds on an above floor panel system with PEX A not glued? Where I live PAP is double the cost of PEX A, so that's quite the upgrade.

Thanks.

Ironman

I’ve never had expansion noise problem on any of our installs, but we always use ODR which mitigates it. 

We always use pex a with plates or staple up applications, but PAP has far less lineal expansion.

Paul Pollets

There are no noises associated with PAP, but it is not typically installed in above floor applications...5/16 Pex is and a heat transfer silicone is used in the grooves for both Climate Panels and QuickTrac. WarmBoard uses 1/2" and when these applications use a motorized mixing valve and variable speed smart pump, there is no noise. PAP is often used to supply the radiant manifold, as it's half the price of copper.

TAG

With ODR and constant circulation -- the only noise I have is on initial start up. I have used 1/2 PAP for a small retrofit plate area I had in one house ... it worked fine and fit into the groove w/o issue.

Typically use regular

hot_rod

The Roth panels have a very tight grip, unless you break the foam under the groove. If you nail the flooring or underlayment that tightens it even more.
PAP is a bit tricker to work with, you need a good uncoiler to avoid kinks and so it comes off and spirals.

I have not tried it, but I think the PERT might be a good match, seems to be more flexible? I like that the EVOH layer is protected in the 5 layer tube.

https://plasticpipe.org/building-construction/bcd-pe-rt.html

WillC

Thanks for sharing your knowledge, really helpful!