Update Your Insulation To Save Energy and Heating Costs

By Matt Weber

Prepare the home for winter to save energy and heating costs by updating your insulation.

When we get cold, we reach for a blanket. We should do the same for our house. As the temperature falls, the heating bills rise, and older homes that were built in the glory days of low-cost energy don’t generally have the required amount of insulation and weatherproofing to heat the house at a reasonable cost. Even newer homes often have only the minimum insulation level to meet local building codes, rather than the preferred amount to heat the home most efficiently. (Lead photo copyright Dumitrescu Ciprian – Fotolia.com)

Using the appropriate amount of insulation for your area can reduce your heating usage up to 30 percent. Insulation levels are specified by R-Value, a measure of the insulation’s ability to resist heat traveling through it. The higher the R-Value, the better the thermal performance of the insulation.

The recommended insulation level depends on the geographic area of the home. According to the Department of Energy, the warm, southern areas of the country should have enough attic insulation to achieve a value of R-30 to R-60. The northern, colder areas of the U.S. require attic insulation of at least R-49 for the system to be cost-effective. The amount of insulation required to achieve a certain R-value depends on the type of insulation being used. For example, 3-1/2 in. of fiberglass will achieve R-13, while 2 inches of rigid foam polystyrene achieves R-10. The R-value will be printed on the package of the insulation product so you can easily calculate how much is required. R-Values of individual products can be added to achieve recommended levels. An R-38 added to an R-11 results in R-49.

Types of insulation range from fiberglass batts and rolls to cellulose, rock wool, spray-foam, rigid foam, various types of blow-in, loose fill, etc. Fiberglass is the most popular type for builders and homeowners.

DIY Insulation

To inspect the insulation of your home, start at the top and evaluate the attic insulation. The attic should have at least 12 inches of insulation. Then examine the exterior and basement walls, and finally floors and crawlspaces.

Fiberglass is inexpensive and easy to install, making it the most popular type of insulation for builders and homeowners. Attics should have a minimum of 12” of fiberglass insulation. (Photo courtesy Certainteed)

Unrolling fiberglass insulation can be an easy and inexpensive method to increase insulation levels. If you install additional fiberglass insulation over existing insulation, be sure to use unfaced rolls or batts. The facing acts as a vapor retarder that helps reduce the amount of moisture entering a wall, ceiling or floor. In hot climates, the original layer of insulation should already have a vapor retarder facing the living area of your home. If you add a second vapor retarder with another layer of faced insulation, any moisture that does get through the first layer may condense on the second. This can cause water stains on the ceiling and could lead to mold and structural damage.