Linoleum over slab with a layer of insulation – Kerdi-board
My daughter’s school (Vermont) has the pre-school on the walk out basement level. The floor is old vinyl tile directly on an uninsulated slab. The floor is cold in the winter and condensation is an issue in the warmer months. Donated carpets are changed out periodically and we did a whole building Air exchange system which improved air quality quite a bit. Headroom is an issue on this floor.
We would like to add a layer of insulation then subfloor material to provide a base for linoleum – a layer of 1″ xps then 3/4 Advantech? This seems the simplest option but I am also considering whether I can get electric radiant into the mix. I am also wondering if we could forgo the plywood if we use Kerdi-board?
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Replies
Robert,
An inch of rigid foam followed by AdvanTech or plywood subfloor would work. The subfloor is fastened to the slab through the foam with TapCon fasteners.
Kerdi-Board is usually used as a substrate for tile. I have no idea whether linoleum manufacturers would support the use of Kerdi-Board under linoleum. I guess you should contact the linoleum manufacturer to get an answer to the question.
Thanks, will do - It seemed that if the Kerdi was rigid enough for tile then maybe it could gain a few R value points for the same thickness. Just an idea.
Robert,
Linoleum, vinyl and other similar sheet flooring are typically installed on an underlayment (usually 1/4" G1S plywood) which is attached to the subfloor. I don't think the warranty on any of them would allow installation directly on the AdvanTech or plywood.