Where there is light, there's heat, at least when it comes to sun rays streaming through your windows. If new windows are part of your green remodeling plan, you'll find value in knowing your windows' U-factor.
The U-factor, or U-value, typically falls between 0.2 and 1.2. The lower the value, the greater the resistance to heat flows, thus providing greater insulation. Another gauge for windows is called the Solar Heat Gain Coefficient, which measures how well the window blocks heat from the sun. Both are ratings adopted by the National Fenestration Rating Council, a trade group.
Up in the attic, green ideas include using radiant barrier paint on the underside of the roof and perhaps spray foam insulation with an R-value, which measures heat resistance, of 39. For an uninsulated attic, an R-value of 30 to 60 is considered good, according to the Energy Star website.
Finally, enlist Mother Nature's help and plant some shade trees. "This isn't talked about a lot, but it's a low-budget item that is very effective,'' says Beere.