What You'll Need
- 1 inch XPS rigid foam insulation
- Plywood
- Screws
- Mastic
- Mesh tape
Step 1 - Foam
Begin by cleaning the basement cement floor thoroughly to remove all dirt and possible mold. Once you’ve done this, cover the floor with 1 inch XPS rigid foam insulation, packing the sheets together as tightly as possible. To prevent heat loss, secure in place with mastic and use mesh tape over all the joins.
Step 2 - Plywood
Lay 1/2 inch plywood over the top on the insulation and screw in place, with screw going down into the basement cement floor. This will keep the floor steady, and the insulation will also provide some cushioning for the feet. Top this with another layer of ½ inch plywood. Screw this into the layer of plywood beneath it.
Step 3 - Flooring
At this stage you have the choice of either leaving the plywood as it is or putting down flooring. The latter is the better option. Without it, the plywood will soon turn dirty as people walk across it. If putting down carpet or a floating wood floor, be certain to add an extra underlay, which will give more insulation.
Source: www.DoItYourself.com
