A Guide to Cellulose Insulation

At Great Lakes Roofing and Insulation Systems, Inc. we specialize in 4 main types of insulation:

  • Fiberglass
  • Cellulose
  • Open-Cell Spray Foam
  • Closed-Cell Spray Foam

In our latest blog post, we featured a piece about open vs closed cell but now we’re turning our focus to cellulose. Cellulose is one of the oldest forms of insulation and is primarily sourced from recycled materials such as newspapers or denim. For this reason, it is coined as the most environmentally friendly form of insulation.



With this composition, a common misconception is that cellulose increases the risk of fire, but the borate treatment prior to installation increases the fire resistance and makes the material unappealing to pesky insects. The structure of cellulose is also favorable in scenarios where there are objects like wiring or pipes in the walls that need to be insulated around. Cellulose is also a great option to soundproof space.



On the other hand, in comparison to other forms of insulation, cellulose has a lower R-value rating at about 3.5 per inch. A disadvantage of cellulose includes a potential decrease in R-value over time (as much as 40%) due to the settling of the particles in walls. Wet spray cellulose is applied during new construction to prevent the settling at the bottom of the wall that comes with the dry pack method, so attics or retrofitted walls are the only scenarios that dry cellulose would be utilized.



As previously mentioned, a convenient aspect of cellulose is that it can be installed in not only new homes but existing walls as well (retrofitting). During this process, a piece of siding (typically above or below windows) is removed and a 1-inch hole is cut into the exterior of the wall. Then, the cellulose is blown into the existing wall, the hole is closed, the piece of siding is replaced, and your older home has BRAND NEW insulation!


Whether you are looking into insulating a new space or working on a home improvement project, Great Lakes Roofing and Insulation Systems, Inc. has you covered. If you would like a free estimate, call (989) 575-0190!