By Eric Forbes

"When it comes to saving energy I used to think I was doing good if I nagged the kids to keep the doors closed when the heat was on," says homeowner and contractor Richard Dudley of Boston. "But a recent gas and electric bills said 'not good enough.'"

It seems the only "good" Richard was doing was heating the air outside his home via his uninsulated walls and leaky windows.

With cooler temperatures upon us, now might be a good time to develop a plan to insulate the whole home against colder, wetter weather and high utility bills.

Insulating the attic is an excellent way to keep your heating and cooling where you want it inside. Photo courtesy of Owens Corning

Do you need more insulation?
Check your attic and sub-floor for existing insulation. If it's there, move on to other areas. Most homes built prior to the 1970's energy crisis were built with less or none of the insulation that is mandatory today. The important thing is to maintain a balance. Overinsulating your attic won't help if you allow air to escape through single-pane windows or non-weatherstripped doors.

R-values mean "real values"
Start by learning how to rate different kinds of insulation. Whether heat is flowing in on a hot day or out on a cold day the R-value, or resistance to heat flow, is the standard measure for all types of insulation. The higher the R-value, the more insulating the product.

Now, find out what R-value is good for what region of the U.S. Check the U.S. Department of Energy or Owens Corning Web sites for the temperature zone maps and the corresponding target R-values for ceilings, walls, floors every nook and cranny in the house. One important consideration when using the map and chart is that the recommendations assume that there are only minor air leakage through doors and windows. (If doors and windows are not adequately sealed, then weatherstripping should play a big part in your insulation strategy.)

What your insulation project should include
"Here in Fresno (California)," says Mike Chang, a nurseryman who lives in an older Victorian home, "although it doesn't get to freezing very often, we still get frigid nights. We use the heat 24-7. But we get really hot in summer." Mike says he started his insulation project in the attic. Without attic insulation, heat from the interior of the house makes its way into the attic and out the roof. Attic insulation is a good way to go for a DIYer, too, because it's easy to install compared to walls or floors.

The second area of greatest benefit comes from replacing windows. This is because their low R-values contribute to most of a home's energy loss. Even small increases in R-value through double glazing or glass coatings can make a big improvements in your overall R-value.

For walls, choose one of several methods for "injecting" insulation into walls. These methods are popular because they require only small, repairable holes to get the insulation into the walls instead of removing the whole wall surface. Two good choices: cellulose insulation and blown in fiberglass. But because specialized equipment is needed, this is probably not a do-it-yourself project hire a contractor to have it done.

If there is a crawl space under the house it also makes sense to insulate under the floor. To do this, tack up some netting under the floor joists to hold the insulation up and have a contractor blow some insulation past the netting and into the floor joist spaces. This saves the trouble of fitting insulation bats around all the pipes and ducts under the house.

Now the good news
With insulation finally in place there is just one more thing to do – apply for all the rebates! The Energy Star Program and some local utilities offer rebates and actually help make insulation adventures very affordable.