The most common type of home insulation is made from fiberglass. You probably know it as the fluffy blankets lining exposed wall studs or ceiling rafters. Fiberglass insulation can be blown with special machinery, but it’s more often installed by hand as batts (precut sections) or rolls (continuous lengths up to 40 feet). Fiberglass bats and rolls can be easily installed as a DIY project, further lowering the price of this low-cost product. Save even more money by claiming a government tax credit for your improved-efficiency insulation.
Fiberglass Insulation Considerations
Fiberglass batts and rolls often have a factory-applied facing made from kraft paper, foil-faced paper, or vinyl. In addition to holding the insulation together and protecting the insulation’s surface, some facings act as a vapor/air barrier, radiant barrier, or flame barrier. The location of the insulation and your climate determine the type of facing needed. Check local code requirements to find out what type of facing—if any—is needed for your project. Unfaced fiberglass insulation is also available.
Insulation value is measured by R-Value; a higher R-Value denotes better thermal performance. Fiberglass insulation is rated from R-13 to R-49. Energy Star provides insulation level recommendations by climate zone. The Department of Energy offers this zip-code based tool for figuring out insulation levels. Through the end of 2013, if you improve the energy-efficiency of your home by installing new insulation, you may qualify for an energy tax credit of up to $500. See offer details here.
Reasons to Replace Insulation
Insulation is installed during home construction, but it doesn’t always last forever. Although you may decide to replace fiberglass insulation to improve energy efficiency, rolls and bats might also need to be replaced due to water damage or animal/insect infestation.
Fiberglass insulation can last a lifetime, but it might compress over time and lose some of its R-Value. In some cases, fiberglass insulation simply wears out due to old age. If insulation crumbles to the touch, it needs to be replaced. New insulation can be placed over old, clean insulation. Contaminated insulation should be removed before new insulation is installed.
Fiberglass Insulation Average Costs
Fiberglass batts and rolls cost $.25 to $.75 per square foot (materials only). The actual cost depends on the product’s performance (i.e. R-Rating and type of facing).
Professionally installed fiberglass insulation might cost $.50 to $1.00 per square foot or more depending on your location and where in the home the insulation is installed.