Cellulose insulation is a great option and may be the right choice for you and your home.
Cellulose is one of the oldest types of building insulation materials and will forever be a good option for homeowners – because it works. It has a strong list of benefits:
- Cellulose insulation helps save energy
- Cellulose is a very green product
- Cellulose provides a great cost benefit value
- Cellulose helps control sound very well
- Cellulose is fire retardant
How Green is Cellulose? Very.
Don’t let it’s gray exterior fool you. Cellulose is very green. The name is derived from the French word cellule, a living cell, and glucose, which is sugar. It’s plant fibers at its essence. Cellulose has the highest recycled content of any insulation material and also has less embodied energy than fiberglass and other furnace-produced mineral insulation. The recycled content of cellulose is 75 – 85%, comprised of post-consumer waste paper like newspapers. The remaining 15% is fire retardants such as boric acid.
Thermal Performance of Cellulose
The thermal performance of loose filled cellulose compares favorably to other fiber and loose fill materials. The R- value of loose-fill cellulose is 3.8 per inch which is the same as or slightly better than fiberglass or rock wool. This doesn’t represent the whole picture of thermal performance. Other important aspects are how well the building envelope is sealed from air infiltration and convective airflow. In the case of open blow attics it’s critical for the prep to be done correctly. This includes air sealing of penetrations through the ceiling of the building into the attic space. Common examples are junction boxes for lights or speakers, bath or kitchen ventilation fans, plumbing pipes or vents, changes in ceiling height from interior soffits or wall junctions, and stairwells. Detailing the access into the attic is also a very important step. And another important item is protecting against wind wash at the eaves while maintaining air space for ventilation when insulating the floor of the attic.
Job prep also includes various items for safety and the longevity of the structure. These items could be a factor in causing harm to the building components over time. Barriers around chimneys and flue pipes for fire precautions. Venting exhaust ducts for bath and kitchen fans to the exterior to get moisture laden air outside.
Cellulose is very good at fitting around items in walls like pipes and wiring, leaving few air pockets that can reduce the overall efficiency of the wall. Dense pack cellulose can seal walls from air infiltration while providing the density to limit convection, when installed properly.