Because it is so common to install fiberglass batts between the basement and ceiling joists, the more important work is ignored.

When insulating the walls the bottom part of the house is immediately brought into the building envelope. Comfort and energy efficiency are the result of this.

Fiberglass is not recommended on basement walls. 

Rigid Foams advantage on basement walls

Don’t use fiberglass in the basement, use rigid foam boards. Fiberglass loses R-Value, absorbs, moisture, falls out of place and compresses. Rigid foam boards do none of these things.

The normal, standard way was to make 2×4 wood frame walls within the foundations walls. Then the stud bays that were created by the studs would be filled with fiberglass batts. J

Energy Efficiency science and the best contractors both agree that this is something to avoid. The moisture in the basement is not friendly towards fiberglass batts. The moisture is bound to absorb in the insulation leading to wood rot and mold growth.

Rigid Foam- The Best Choice

For the basement walls the right choice is rigid foam insulation. Our top quality boards at the home Insulator will deter mold and will not absorb moisture. No compression, or R-loss will take place and cold air will stay out.  We can also install boards with radiant barrier siding for additional energy efficiency leading to more comfort and savings.

The boards are installed directly against the foundation walls in the basement. They are secured with masonry fastener and adhesives. Sometimes the local codes require other fire-proof materiel such as gypsum board to cover the Rigid Foam.