Combining a good thermal resistance value with exceptional airtightness, cellulose insulation makes a great thermal insulator.
Cellulose insulation has an R-value (thermal resistance) comparable with alternatives such as fibreglass, rockwool, and expanded polystyrene. However, its blown installation method means cellulose insulation tightly packs every corner of a void. This provides superior airtightness when compared to to most other types of insulation. Alternatives are manufactured in rolls, boards, or batts that are practically impossible to fit tightly in awkward spaces. Even tiny gaps leak heat.
Cellulose vs Fibreglass Insulation
In practice, the performance of cellulose insulation significantly exceeds that of fibreglass. Separate studies by the University of Colorado and Wimpey Homes show that cellulose reduces energy costs by around 25%.