Q: What cost-effective improvements will make my home comfortable year-round?
A: It isn’t pretty, but insulation and air sealing can save you money and make a big difference in comfort and energy use.
Insulation is rated in R-value. The R stands for resistance to heat transfer. The higher your R-value, the slower the heat transfer—meaning less wasted energy.
There are different types of insulation, including fiberglass batts, blown fiberglass, cellulose and foam. Each has its own R-value listed on the packaging.
To determine the R-value of your existing insulation, multiply the number of inches deep by the R-value per inch for the type of insulation.
Recommended insulation levels are based on your geographic location.
Where to Insulate
The typical locations for insulation are the attic, walls and floor. If you have a forced-air heating or cooling system, your ductwork should be insulated, too. You want a consistent thermal barrier around your home for maximum efficiency.
Attic insulation minimizes energy waste and can help maintain a more consistent temperature throughout your home. Combined with air sealing, it also can prevent ice dams from forming on roofs in cold climates.
Attics can be insulated using batts or blown-in insulation. Recommend R-values range from R-30 to R-60.
You can build a raised platform for attic storage with room for insulation underneath. Add insulation and weatherstripping to access doors or hatches.
Exterior walls and walls separating heated and unheated areas of the home—such as garages or enclosed porches—should be insulated to an R-value ranging from R-13 to R-21, based on your location and wall construction.
Wall insulation can be installed during construction or a remodel. If your home wasn’t insulated when it was built, you can have the insulation blown in by a contractor. Blown-in options include cellulose, fiberglass and foam.
Your home should be insulated between the floor and crawlspace or unheated basement. If your basement is heated, install insulation in the box sills—the area between the foundation and floor of the home’s main level.
Consider building and insulating the exterior walls in the basement or installing foam insulation on foundation walls. Check your local building code requirements. Recommended R-values for floor insulation range from R-13 to R-30, based on your geography.
Insulate heating and cooling ductwork in unconditioned spaces to prevent energy waste.
The Importance of Air Sealing
Think of insulation as a cozy sweater and air sealing as a windbreaker for your home.
You know that cozy sweater is no match for winter winds, so you need an extra layer to stop them from ripping through. The same goes for your home.
Air sealing prevents drafts and air infiltration from outside. It can improve efficiency, comfort and indoor air quality.
Air sealing can be done as a do-it-yourself project, but finding and properly sealing air leaks is challenging. Check with your utility or hire a contractor to complete a home blower door test and seal leaks.
Typically, air sealing is done around plumbing and electrical penetrations with spray foam or caulk. If using spray foam around gas appliances, temporarily turn off pilot lights. Spray foam is extremely flammable.
Sheet metal and high-temperature heat-resistant caulk should be used to seal gaps between framing, chimneys and metal flues.
If you are considering a DIY approach, protect yourself when going into spaces with insulation with a mask or respirator, Tyvek suit, gloves and kneepads.
If tackling an air-sealing project on your own, research best practices for proper home ventilation.
Before going DIY, contact two or three local contractors for a project estimate. It is possible a contractor can acquire cheaper bulk pricing on insulation.
Making insulation and air sealing a priority adds comfort, efficiency and savings to your home.