Open Cell And Closed Cell Spray Foam Insulation: What's The Difference?

by Derrick Gordon

When installed properly, spray foam insulation had many benefits, such as preventing air and moisture infiltration, adding strength to building structure, resisting sagging over time, keeping out dust and pollen, and reducing wear on your HVAC equipment. There are two types of spray foam: open cell and closed cell, so you may be wondering what's the difference? Does it matter which type is used in my home?

What Is The Difference?

There are a few major differences in open cell and closed cell foam. Open cell foam has tiny foam cells that are not completely closed, so air can enter into the the cells,filling in the empty space. This makes the foam softer and weaker than the closed cell type. 

With closed cell foam, all the tiny foam pieces are packed together and closed. Its cells are filled with gas, not air, which helps the foam rise, expand, and work as an effective insulator. The cells can also be formulated to have a variety of characteristics, with the most important being density and size. 

What Do These Differences Mean To Homeowners?

The different characteristics of these two types of spray foam insulation does matter to you, the homeowner. While both types are commonly used in building applications, the choice of which to use can depend on a few factors, such as cost, strength, and R-value. 

The advantages of closed cell foam makes it more the more expensive choice, but it does offer more strength, a higher R-value, and greater resistance to air and water vapor leakage. It is often good type of spray foam to use for roofing applications, but you can use it anywhere in the home. However, because closed cell foam is denser, more material is required. 

Open cell spray foam most often used for interior walls. It is more sponge-like than open cell, and it good barrier for air. This type is also provides sound reduction. Unlike closed cell foam, it is not recommended for outdoor application because its open cells can absorb moisture.

Both types are an alternatives to fiberglass insulation. The foam is sprayed from a gun and expands into areas. It is often used to wall cavities, concrete slabs, and into holes drilled into finished walls. 

If you unsure which type of insulation is best for your home, you can contact a local insulation contractor, like High Country Insulation Inc., to discuss the different types available and decide which type fits your budget and your needs.