There are a variety of insulation types and this means a variety of ways and techniques are possible for installing insulation materials. Further, insulation is not only made from a variety of materials, it comes in different forms:
Cellulose comes in a loose-fill form and cellulose batts produced from cotton or paper fibers are available, fiberglass is available as both loose-fill and batts, while denim comes in batt form only. Spray foam insulation is a two-part chemical that is mixed and sprayed at the time of installation.
It is possible for the homeowner to install some of these insulations. However, CIMA recommends using a professional installer to ensure proper installation and the best performance, especially on larger projects such as new homes. In addition, not all insulation contractors are knowledgeable about installing every type of insulation. Homeowners should seek contractors experienced with the type of insulation they intend to install in their home. Below are some basic guidelines for installing cellulose insulation.
Cellulose insulation is installed with a blower. Insulation is directed into a wall cavity or attic using a long hose that is connected to a blowing machine filing the cavity or blanketing the space. To achieve the desired R-value, install the amount specified on the coverage chart printed on the bag. (Cellulose insulation coverage charts are developed to take into account any settling of the material, so following the directions will yield the desired R-values for years to come.)
As a practical matter, a homeowner should only consider installing cellulose insulation in their attic, either where there is currently no insulation or as a cap over existing material. The rental blowing machines available at home centers don’t have sufficient capability to properly densepack a wall cavity.
In new homes or room additions, cellulose can be applied dry, either blown-in behind a fire-rated membrane that is stapled to the studs, or damp-sprayed by an installer using a specialized spray truck. (Even though there is a small amount of water added to the material during this process, the insulation dries quickly and meets all ASTM requirements for preventing mold.)
A significant advantage of blown-in or spay-applied insulation over batts is that it completely fills the wall cavities, particularly around electrical outlets and other penetrations, blocking air movement through the wall.
Thousands of older homes in the U.S. are under insulated costing homeowners hundreds of dollars annually in increased utility bills and adding impacts on the environment. Upgrading or adding insulation in exterior walls of existing homes requires the right insulation material installed by a properly trained professional. Blown-in cellulose insulation is the perfect product for retrofits. A trained contractor can typically do such installations without major renovation to the existing walls.
Retrofitting with cellulose insulation typically does not require demolition of existing walls. A trained insulation contractor can complete the process with limited disruption to the dwelling while homeowners remain in their homes. Learn more about retrofitting a home with cellulose insulation.