To be sure, over time, many such investments pay for themselves through lowered fuel bills. You'd have to install storm windows or double-pane windows that have argon gas between the panes. No doubt, if you are going to remodel or replace or build a house, you'd be wise to do it in an energy-efficient way. But actually, that costs them more money because it takes so much more energy to reheat everything. You aren't just reheating air, you are reheating your furniture, the clothes in your closet.
Leaks can be almost anywhere.
Air comes in and out where plumbing pipes and electrical wires enter, through gaps along the baseboard, around window air conditioners and mail slots. If your windows rattle or you can see daylight around the frame, a leak is likely. However, what you want to do is eliminate drafts without eliminating air exchange entirely, said Colagioia. That is, all the pollution from dust, mold, germs, etc., is trapped inside. He suggests walking through your home when all doors and windows are closed with a lighted candle or smoking incense stick.