Insulation is your home's all-purpose force field against high energy bills. It minimizes heat transfer in winter and summer, provides ventilation to control moisture and makes your home more livable.
Bringing your attic insulation up to code for your region is one of the most cost-effective ways to winter-proof your bear cave. The Department of Energy can get you started with its ZIP Code Insulation Calculator.
But before you blow insulation, be sure to seal all ductwork, plumbing and cable TV penetrations. Leaky ducts can account for 10 percent to 30 percent of heating and cooling costs.
"Most houses leak like sieves," says Lindstrom. "Attic access doors are one of the biggest offenders. By building an insulation dam around the scuttle opening and installing an insulated lid on it, you'll save big."
Cost: $500 to $1,000 to bring a typical attic up to code. Lindstrom recommends earth-friendly chopped cellulose, which is chemically treated to repel fire and insects and retains its loft better than fiberglass.
Savings: 20 percent to 30 percent off your monthly bill, with return on investment in as little as one year.