Foundation Insulation

Insulating Concrete Forms

• Insulating concrete forms (ICFs) are a type of insulation that is built into the walls of the foundation as it's being poured. There are two main types of insulating concrete forms. The first type uses foam boards that interlock together and are fastened together with plastic ties. They are then placed inside the wooden forms to await the pouring of the concrete. After the concrete cures, the forms are removed. The other type of insulating concrete forms are hollow blocks that are stacked together like bricks. The concrete is then poured into the center of the blocks.

Foam Board Insulation

• Foam board insulation is similar to insulating concrete forms in that it consists of boards made of foam. The difference between the two types of insulation is that while insulating concrete forms are built into the foundation, foam boards are installed on a foundation that has already been poured. The foam boards are installed by covering the back of the boards with Styrofoam adhesive and placing them on the walls of the foundation in a staggered pattern. The joints between the different panels are then covered with installation tape.

Fiberglass Insulation

• Unlike foam board insulation, fiberglass insulation is not installed directly on the foundation walls. Fiberglass insulation is used to insulate finished walls, such as the walls of a basement that's used as actual living space. To use fiberglass insulation, you first need to construct wall frames, then raise them and nail them to sill plates, which are pressure-treated boards bolted to the floor along the foundation walls. The insulation is unrolled and placed in the gaps between the wall studs. Drywall is then installed over the framed walls. One drawback to fiberglass insulation as opposed to foam board insulation is that the fiberglass must be handled carefully, as it can irritate skin and cause damage to your lungs if inhaled, so wearing gloves, a mask and goggles is imperative when installing it.

Spray Foam Insulation

• Spray foam insulation is a type of insulation that is sprayed on a surface as a liquid, then expands as it dries. It is most often installed on metal surfaces, or on oddly shaped surfaces where foam board insulation and fiberglass insulation are not practical or unusable. Because it's sprayed on as a liquid, it adheres directly to any surface, providing a tight seal against moisture and drafts. It's also very effective at blocking sound, and can even help strengthen the foundation.