Insulation added to your attic helps keep your home warm during the winter and cool during the summer. You pay good money to keep your residence at a comfortable temperature, and the costs to do so will likely continue to rise. Insulation in your attic helps keep the climate controlled air from escaping. By boosting the amount of attic insulation from R-11 to R-49, or about 19 inches, you can expect to save up to $600 per year. One simple check to see if you need more insulation is to look across your attic floor. If your current insulation is at or below the height of the joists, then you probably need to add insulation. If you can’t see the joists or the insulation is well above the tops of the joists, you’re probably in good shape and won’t find much savings in adding more.
You can expect to pay a professional about $1,500 to insulate a 800-square-foot attic. This investment can be recouped in about three years. Feel like doing the job yourself, you’ll spend about half that.
There are three common methods for adding insulation to your attic:
Roll-On or Blanket-Type Insulation
These rolls of fiberglass batts are designed to fit between typical roof framing members and are either 15 or 23 inches wide. If your attic already has insulation, it is suggested you roll out the batts at right angles to the insulate over the framing members. This material is the best for do-it-yourselfers. Don’t forget to compress the insulation for the best efficiency results.
Loose-Fill or Blown-In Insulation
This type of insulation is typically installed by a contractor as a special machine is used to shoot streams of loose-fill cellulose over the attic floor. Loose-fill insulation has an advantage as it does a superb job of filling in small crevices and hard-to-reach spots.
Sprayed Foam Polyurethane
If you plan on turning your finished attic into a living space this is a good choice. The sprayed foam polyurethane is applied to insulate the roof members instead of the attic floor. It molds to the roof rafters and also blocks water vapor. Expect to pay about double the per-square-foot costs compared to the previously mentioned insulation types.
To get a more accurate idea of how much insulation you should add use the Home Energy Saver online energy audit tool.