Insulate Basement Floor With Rigid Foam

Attach the tongue and groove insulation boards to the concrete wall with adhesive.

Insulate basement floor with rigid foam.

If the basement floor is wet hire a professional find the source of the problem and fix it before doing anything. Foam board insulation is easy to cut with a circular saw with a masonry blade or scored with a utility knife and snapped like you would drywall. For a basement remodeling project consider insulating basement walls with foam board. It gets rid of any air movement behind the walls.

Once the insulation has been placed you will want to cover it up with plywood. Step 5 cover with plywood. There are several ways to install subflooring above the rigid foam. If the concrete floor is dry and reasonably level insulate directly on top with a rigid foam insulation that is impervious to moisture air leakage and radon gas.

You can use either one or two layers of plywood or osb and the subflooring can either be fastened to the concrete with long tapcon screws or it can simply float above the foam. For new construction use rigid boards to insulate slabs and the outside of foundation walls. It s like a beer cooler which has rigid foam insulation too. The best insulation to use is rigid foam which is largely unaffected by moisture.

I posted on the basement insulation site but i ve developed my thinking a little more and now ponder whether this would work for the concrete basement floor that i very much want to finish in ceramic tile 6 poly 1 xps foam 3 4 advantech 1 2 hardibacker thinset and 1 4 tile. Except for the deep south. 2x4 sleepers installed on center every 12 16 inches and fastened down with rigid foam insulation 1 1 2 inch thick placed between the sleepers. To attach the insulation you can use screws with large washers a special adhesive made for adhering foam board insulation or for smaller pieces you can seal them in with caulk or spray foam.

Rigid foam is combustible so by code must be sealed in by a thermal barrier of either drywall or 5 5 of roxul with the latter providing added insulation in a critical heat loss zone provide sound dampening to the above floor. Basement wall insulation is recommended in most of the u s. If your basement slab lacks sub slab foam you ll have to install the insulation above the slab. Energy savings are about the same whether you insulate on the interior or exterior.

After the rigid foam is on the floor and walls it can be studded over. Step 4 install the insulation. Place your rigid foam insulation between the sleepers in the open areas. Concrete basement floor.