As most heat is lost through the upper part of the foundation walls, basement floor slabs are seldom insulated. For improved comfort, moisture control and radon reduction, apply a moisture barrier to the floor or seal the floor to prevent moisture accumulation between the insulation and the slab. Alternatively, you may install a floor drainage system under the new floor.

If you are installing or replacing a concrete slab floor, this offers an excellent opportunity to have in-floor heating installed or to have it made radiant-ready. Radiant-ready is where insulation and heating lines are installed before pouring the new slab, allowing for future use of radiant heat (including solar-generated) in this area. Consult a heating contractor with experience in hydronic in-floor heating.