Quik-Therm warm floor
shaner1982
| Posted in General Questions on
Just wondering if anyone has used this product before? Thinking of putting it directly on my basement concrete slab and then putting the laminate directly on top (no plywood).
There doesn’t seem to be much information out there about this product though.
Is there any advantage of putting plywood on top if I’m just going with a floating floor?
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Replies
Shane,
As far as I can tell, Quik-Therm is simply EPS rigid foam with a foil facing. There's nothing wrong with that -- it's an environmentally benign type of rigid foam, and the facing makes it easy to tape.
Other manufacturers also make EPS insulation, of course, so you have many brands to choose from. Many green builders use recycled (reclaimed) EPS, which costs one-third to one-half the price of new rigid foam.
I doubt laminate flooring would meet spec as the code-required thermal barrier against fire for the foam the way half-inch OSB or plywood does.
Then there's the rockering issue: Where a seam of laminate is within an inch or two and parallel with of the seams of the EPS the dynamic loading of the floor will permanently deform the edges of the EPS over time, and you'll develop some soft spots.
You can still float the whole thing, but put a layer of OSB/ply down staggering the seams with those of the EPS by a foot or so to prevent the rockering problem. Using t & g OSB or plywood and gluing it to the EPS with foam-board construction adhesive would allow you to float the whole thing.
Make sure the concrete is pretty flat first, or you'll end up with some bouncy sections. It doesn't hurt to through-screw the OSB to the slab with masonry screws to keep it all from moving on you. If there are large seasonal swings in the indoor humidity you could end up with some "potato chip curl" if it's completely floating.