The material properties of 4x8 pvc foam board, including light weight and rigid structure, make them robust both for outdoor use and interior finish, being immune to rain and resistant to wind and sunlight. By insulating the basement on the concrete block with rigid pvc board, extra living space can be added. And the installation process is easy and follows the same installation procedures, but it still requires people's attention.

Measuring the area of the room by running a tapeline along the first wall is necessary. Write down the measurement of the width and the height of the wall from the floor to the ceiling. At last, work out the total square footage of the first side of the room by multiplying the two measurements. After the measurement, check the foundation for cracks or leaks and seal any with concrete patching compound or aerosol expanding foam insulation.

After the basic work, caulk around the rim joist and any pipes, wiring or vents, then use aerosol expanding foam insulation and apply it by using the extension nozzle which comes with the foam. Next, position rigid foam boards vertically against the wall and use a level to make sure that they are flush and plumb against the foundation. The edges are recessed to form a channel for installing the furring strip. Measure and mark the wall every sixteen inches for the furring strips. Insert masonry screws into the furring strips with a power drill. Hold the first furring strip in place at the mark and insert a screw every eight inches down the middle of the board to secure it to the concrete. Move down sixteen inches and install the second furring strip the same way. Continue around all the walls until the strips are all attached.

The installation of foam board should be around electrical outlets. Then place the board in position in front of the outlet rough-in and press. The outlet will leave an impression on the back of the foam board, which is then easily cut by using a utility knife. Install drywall panels over the foam board insulation and attach the drywall to the furring strips with masonry drywall screws. Tape the seams of the drywall. Apply drywall mud to the taped seams and the impressions left by the screws. When dry, sand lightly and paint the drywall with regular interior wall paint.