Basement slab insulation
I am working on insulating my basement from the interior. I would like to install a 1″ layer of EPS as shown in the Fine Homebuilding “The Stay-Dry, No-Mold Finished basement”. At this point we are about to pour concrete around the perimeter of the basement where we installed a drain tile, as well as a new 10×10 slab in one corner of the basement. Is there a certain amount of time I need to let the new concrete cure before covering it with the EPS? If I have access to commercial polysio, is that ok for use over a basement slab?
Thanks for any feedback
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Replies
Charles,
Your slab will continue to cure even if it is covered with rigid foam, so you can pursue your plan after just a few days, as long as you aren't encountering any problems with your TapCon fasteners.
Do you know whether your existing slab has polyethylene under it? Many older slabs don't. If I were you, I would stick with EPS or XPS in this location, in case the older slab ever got wet. Polyisocyanurate doesn't perform very well when it gets wet, and it won't have the same compressive strength as XPS or EPS.