Spray Foam Types as Attic Insulation

Last week we discussed whether or not spray foam is right for your attic in order to keep it dry and energy efficient. This week we will be touching on the differences between the two major types of spray foam that is commercially available, open-cell and closed-cell. Each of these types of foam insulation are excellent options, depending on where they are used and what your goals are.

Type of Spray Foam: Closed-cell

Closed-cell insulation being applied inside a wall.

Spray Foam Types: Open-Cell

It is also referred to as half round foam. The foam comes with an R-Value of 3.5-3.6 per inch; its density is about 0.5 pounds per cubic foot. The low-intensity foam is mostly made from biological materials, carbon dioxide and water is applied as a makeup. Open cell consumes very few materials than closed cell. It comes with lower R-value. Open cell requires vapor retarder such as gypsum wallboard. It is riskier when you use it for roof sheeting. When considering open-cell we would like to discouraged you from applying this in a cold climate area unless you have an extra barrier in place. It is also necessary to take into consideration the money you will spend installing open cell insulation and the effectiveness of the foam.

 

Spray Foam Types: Closed-Cell

It is also referred to as two –pound foam. It is denser than an open cell for about 2 pounds per cubic foot. R-Value for the closed cell foam is about 6-6.5 per inch. Due to its thickness, it is expensive than open cell types. It comes with an in-built vapor retarder. Closed-cell spray foam has a permeance of about 0.8 perms. It can easily handle cold climates without the addition of drywall or board. The closed cell utilizes hydrofluorocarbons (HFCS) as its makeup. It has been noted to have high global warming effects. If you like to go green, then avoid it.

If you need pricing on spray foam insulation, then you need to contact a professional today.