Energy Vanguard

 Anyone who's been down under a house with a vented crawl space knows that it's not a pleasant place. There are, of course, a lot of critters—spiders, mole crickets, cats, possums, snakes,... Fiberglass batts in the floor are falling out all over the place. Exposed soil evaporates great quantities of moisture into the crawl space air, as do foundation walls against damp soil. This humid air is the reason that crawl space vents were initially made a requirement in building codes, the idea being that the vents would allow the humid air to leave the crawl space.

If you're looking for cost-effective energy retrofits, the answer to this question is usually no. In many homes, even older homes, windows come in at third or fourth in the list of building components that contribute to the heating and cooling loads. Often, the two biggest loads are infiltration and duct leakage, so getting out the spray foam, caulk, and mastic will save you a lot more money on your energy bills than replacing the windows—and they cost less, too! Another item that's usually higher than windows in the list of cost effective improvements is floor or ceiling insulation.