What is the best way to insulate a basement concrete floor?
Moved into house with an attached room next to a garage. I want to turn the attached room into a painting studio. The walls and ceiling of the attached room are insulated. Unknown the amount of insulation. Also unknown if insulation under the slab floor but built in 2008 so I assume some insulation under slab. Two issues: the level of the garage floor is same as the attached room so some concern about exhaust fumes entering the room.
Also the attached room is cold (however two radiant panels have helped greatly). Wondering if I were to add 4" of foam on top of the concrete floor of the attached room, then two layers of 3/4 plywood, or 3/4 OSB, on top of the foam with staggered seams, if that might be enough to help keep the space warm and eliminate the concerns of garage fumes entering the space by raising its height?
Also, does adding insulation on top of the concrete floor potentially create any future problems with moisture. And does the insulation and plywood or OSB added on top of the concrete lessen the effectiveness of the radiant heat being absorbed into the concrete floor mass and releasing that heat back into the room?
We are in Winnipeg, climate zone 7a
Insulating a slab from above in a cold climate like Winnipeg is a smart move to improve comfort. Since it was built in 2008 it likely has some insulation, but not a lot, so adding 4 inches of insulation will significantly reduce heat loss and keep the floor and your feet warm. There is nothing wrong with EPS foam, you can also use mineral wool which handles moisture better in the event there ever is any flooding
You will lose the benefit of thermal mass, but we would suggest the benefits of improved insulation more than makes up for it. This article would be very helpful in your situation and will prevent the moisture issues you are wise to be aware of -
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