Foam insulation is made up of a polymer (such as polyurethane or modified urethane) and a highly reactive foaming agent. The two components are kept separate until they reach the nozzle of the spraying machine when they quickly react creating a substance that can expand up to 100 times its original size.

The foam is sprayed either directly onto the surface or through holes (in the case of retro-fitting) and expands to fill even the smallest nooks and crannies making an air-tight seal and thus eliminating the escape of air, energy, and money.

There are two types of spray foam insulators: open-cell (isocyanurate) and closed-cell (polyurethane). Open-cell types allow for the infiltration of vapor, while the closed-cell provides superior insulation and serves as a vapor barrier.

Each type has its advantages in different situations. Review the following advantages and disadvantages to see if this material is right for you.

Advantages of spray insulators:

• They have higher R-values per inch than traditional batted fiberglass. R-value is the measurement of thermal resistance used in the construction industry today. The higher the number a material is, the more effectively it insulates.
• It blocks air flow by making a tight seal around wires, electrical boxes, and in all tight spaces.
• It can serve as a vapor barrier when a closed-cell variety is used.
• It acts as a sound dampener as well.
• It can be used to retrofit a home for thermal efficiency.
• When retrofitting, it is the cleanest (no dust) and most effective option.
• It can actually improve the structural stability of the building.
• It can be used in places where traditional materials cannot such as between rafters and joints.
• When the house expands and contracts the material does the same, always providing that air-tight seal.
• It can be applied in small quantities.
• It does not shrink, loose shape, or biodegrade.
• Some kinds are fireproof.

Now it is becoming increasingly popular to insulate your home with spray foam insulation. However installing this type of insulation is not that easy, and should be left to professionals.

By: Andrew Stratton