Staple up Install Question/Idea

Kungur

I was wondering if there would be any benefit to install aluminum sheeting on the underside of a subfloor before installing the pex and the transfer plates. My idea is that it would "protect" the pex from any nails that are not cut off flush and remain as little nubs.

Gordan

Mixed feelings

If you're using extruded plates (which you should definitely consider doing for staple-up) then you already have .05-.065" of aluminum extrusion between the pex and the subfloor. Getting even more aluminum in there would almost certainly improve heat distribution IF it can maintain tight contact with the subfloor. Would it be worth the extra cost, even in the best case? Who knows - I haven't seen any estimated output charts for such an arrangement.



And that's the big IF. Even without little nubs of nails sticking out of the floor and acting as little stand-offs, subfloors and the aluminum sheeting may not be flat enough to maintain solid contact over such a wide area. Remember that heat transfer plates transfer heat through conduction - air gaps between the plate and the subfloor kill conduction and detract from the benefits of transfer plates.



My instinct would be to do everything possible to get rid of the nail stubs.

BCMatt

Cut the nails

Just finished installing a whole whack of the extruded plates for my staple up.

I ended up cutting the protruding nails flush with the bottom of the subfloor with either my demo saw or a hand held metal hacksaw blade (use the pull stroke). Didn't take too long and gives me nice, well fitting contact all the way.

I think this went a whole lot faster and cheaper than trying to lay down more aluminum, which won't get proper contact anyway.

That's my 2 cents.



Matt

NRT_Rob

gigantic noise concern

additional cost, hard to ensure good contact... basically no, no and no.



get a cutting wheel for a grinder and have some real fun for a weekend.... weeee!