Blown-In Insulation Toronto

Blown-in insulation is loose-fill insulation material (cellulose or fiberglass) that is installed using a specialized blowing machine. The machine breaks up the insulation into small pieces and propels it through a hose into the target area, where it settles to fill the cavity evenly. It is one of the most cost-effective ways to insulate attic floors and retrofit wall cavities.

Cellulose offers a higher R-value per inch (R-3.5 vs R-2.5 for fiberglass), better air sealing due to its density, and superior fire resistance because it is treated with borate. Fiberglass does not settle as much over time and is less affected by moisture. For most Toronto attics, we recommend cellulose for its superior thermal performance and fire resistance.

To achieve the Ontario Building Code recommended R-50 with cellulose, you need approximately 14-15 inches of depth. For R-60, which we recommend for optimal performance, you need about 17-18 inches. With fiberglass, you need approximately 20 inches for R-50 due to its lower R-value per inch.

Yes, in most cases blown-in cellulose or fiberglass can be added directly on top of existing insulation to increase the R-value. This is called a 'top-up' and is the most cost-effective way to upgrade an under-insulated attic. The exception is if existing insulation is contaminated, water-damaged, or contains vermiculite, in which case removal is recommended first.

Blown-in cellulose insulation in Toronto typically costs $1.50-$2.50 per square foot for attic installations, depending on the target R-value and existing conditions. A typical 1,200 sq ft attic upgraded to R-60 costs approximately $2,000-$3,500. Wall retrofit installations cost more due to the additional labour of drilling and patching access holes.

Yes, all blown-in insulation settles somewhat after installation. Cellulose typically settles about 15-20% over the first few years, which is why professional installers over-fill to compensate. Fiberglass settles less, approximately 5-10%. We always install to the settled R-value target, ensuring your insulation performs as rated for its entire lifespan.