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I am remodeling an existing utility room into a bathroom and laundry. The existing cement slab floor is sloped to an old drain and the floor needs to be leveled, in addition to adding radiant heat via “Easy Heat” electric resistance wires. I would like to insulate the slab prior to pouring the self leveling concrete, which will probably be 1 – 1 1/2 in. deep. I have considered using thermoply or 1/4 in styrofoam. The thermoply, being foil faced and reflective, might be superior. I know I won’t get much insulation value, but any barrier would be better than none. Because the poured self leveling concrete would be floating on this insulating layer, will this increase the chance of cracking later on? I’m planning on tiling the floor.
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Replies
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FWIW, I
i think,
but don't know for sure, that reflective surfaces need to in open air to do any good.
*Rigid insulation has designed capacities. This means it can deform under load of 20#, 40#, 60#, etc.--whatever the panel is designed for. So, yes, it can increase the likelihood of cracking if you do not use an appropriately rated (appropriate density) product. Your 1.5" thick topping layer may, in practice, be sufficient to spread the foot-traffic loads mitigating cracking however. To be on the safe side, use a product designed for roof traffic (e.g., 60# density or better.Cameron
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I am remodeling an existing utility room into a bathroom and laundry. The existing cement slab floor is sloped to an old drain and the floor needs to be leveled, in addition to adding radiant heat via "Easy Heat" electric resistance wires. I would like to insulate the slab prior to pouring the self leveling concrete, which will probably be 1 - 1 1/2 in. deep. I have considered using thermoply or 1/4 in styrofoam. The thermoply, being foil faced and reflective, might be superior. I know I won't get much insulation value, but any barrier would be better than none. Because the poured self leveling concrete would be floating on this insulating layer, will this increase the chance of cracking later on? I'm planning on tiling the floor.