How much insulation should my house have?

"Insulation," says Bob Vila, host of the nationally syndicated TV program that bears his name, "is the most efficient energy-saving expenditure." Vila says homeowners should check attics to determine the amount of insulation already installed. "Most homes built before 1980 have inadequate insulation," he said, noting that if insulation between the joists of the attic floor comes only to the top of the joist, it probably makes sense to install more insulation.

The U.S. Department of Energy recommends home insulation R-values based on where you live. These recommendations are detailed for various sections of the home including walls, ceilings, and basements. Click here to view these R-value recommendations on a U.S. map or view these recommendations from the R-value calculator.

Be sure your new home complies with current building code requirements for insulation. These building codes establish minimum levels of insulation for ceilings, walls, floors, and basements for new residential construction.