Which Type of Cellulose Insulation Is Efficient & Affordable?

Understanding Cellulose Insulation

• Manufactured largely from recycled newspaper, loose-fill cellulose insulation is ideal for use in attics, behind existing walls and in new construction. Cellulose insulation comes in three primary forms: dry cellulose, stabilized cellulose and spray-applied cellulose. Each variety has been treated to make it fire-resistant, mold-resistant, and insect-resistant. Unlike fiberglass, the material is not scratchy and contains no formaldehyde -- a carcinogenic chemical. Loose-fill cellulose is more effective at blocking air leaks than fiberglass batts or rolls and offers 20 to 30 percent greater insulating ability per inch as measured in R-value. As a result, heating and cooling costs will be significantly lower.

Cellulose Insulation In Attics

• Dry cellulose can be poured into exposed attic spaces without the use of heavy equipment. You may want to follow up by applying a vapor-permeable membrane over the joists to prevent cellulose dust from spreading. You could also install stabilized cellulose insulation using a blower machine, which adds a small amount of moisture to the cellulose. Stabilized cellulose insulation eliminates the problems caused by dust and settling. Portable blowing machines are usually available for short-term rental.

Cellulose Insulation for Existing Walls

• Many older homes were built when heating fuel was cheap, so no installation was installed at the time of construction. Dry cellulose insulation can be blown into empty wall cavities either through attic openings or through temporary holes drilled through the walls slightly beneath the roof or ceiling level. The cellulose will flow into all areas of the cavity, wrapping snugly around conduits and pipes concealed behind walls. A blowing machine is required for proper installation.

Cellulose Insulation for Remodeling or New Construction

• Before the drywall is installed, wet-spray cellulose can be sprayed in place using a blowing machine that adds moisture as it dispenses the cellulose. Wet-spray insulation adheres to exterior walls and studs and fills the gaps with greater accumulated R-value than fiberglass materials do. Another option is to blow dry cellulose insulation behind a tough vapor-permeable membrane that is firmly attached to the studs. Either type of cellulose insulation typically results in lower energy bills than you get with fiberglass insulation.