Revamping your home's insulation is one of the best ways to improve the efficiency of your heating and cooling system. Besides saving money and energy, insulation will block noise from the outside and make your home feel more comfortable.
What You Should Know
- Properly insulating your walls and ceilings can save 25% of your home heating bill and 2,000 pounds of carbon dioxide a year.
- Heat will always flow to an area that's cooler. Insulation restricts heat flow, which means your furnace or air conditioner won't have to work as hard to keep your house comfortable.
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Insulation is rated by its ability to resist heat flow, called the
R-value. The higher the R-value, the better the insulation. By putting
new insulation on top of old insulation, you add the R-values of the
two together. You'll find the R-value printed on the bag, the label or
the insulation itself.
Easy Things You Can Do
Is Your Home Already Insulated?
- Not sure? Start with your attic, the most important location to insulate in your home and the one with the most potential energy savings. Look between the joists--the place most likely to be insulated. Is the insulation dry, spread out evenly, and thick?
- Next, check your basement, look between the floor joists or draped down the foundation walls.
- Finally, to check to see if your walls are insulated, turn off the power to an electric outlet in an outside wall. Remove the switch plate and shine a flashlight into the opening to see if there is anything besides air between the studs. Also, on a cold evening, touch the wall in a heated room and see if the surface is cold.
How to Insulate
Insulating walls in existing homes involves drilling holes between each set of studs and blowing in insulation, a job for an experienced contractor.
Attics and basements are easiest to insulate, and they're within comfortable reach of the do-it-yourselfer. Some general guidelines:
- If insulating your home yourself, be sure to wear gloves and use a respirator for safety's sake.
- Remember to use good ventilation.
- Never compress batts of insulation together: it's the air between the insulation that keeps you warm.
- Insulation can be made of a number of different materials such as fiberglass, or rigid plastic foams of various sorts, but why not try cellulose: made from shredded newspapers, or denim, it's a great way to recycle.
- Insulation is measured by its "R-value"--its resistance to heat flow. If you double the R-value, you cut heat loss in half. The state of California recommends insulating your attic to at least R-38, ceilings to R-30 or R-38, your exterior walls to at least R-19, your crawl space and basement ceilings to at least R-11, raised floors to R-13 or R-19, and your heating ducts to at least R-6.
- Install a "vapor barrier"--such as good-quality vinyl paint--on the inside face of insulation to keep warm, moist air from the house from infiltrating the insulation and dampening it. When wet, or dampened by water vapor, insulation loses most of its insulating value.
- Install proper venting in attics and crawl spaces to prevent moisture from becoming trapped in the insulation.
Sources: 51 Easy Ways You Can Prevent Global Warming and Save Money, by Jeffrey Langholz, PhD, and Kelly Turner.