The right insulation will keep your home comfy and your energy costs low. Here’s how to calculate how much you need and what kind to buy. Adding insulation can be a low-cost way to cut energy bills.

Question: I know you have talked about insulation before and you keep mentioning something about a value for the insulation and how much is needed. Where can I find information about my home area?

Because warm air rises, the attic is the best place to start, particularly for those in colder climates. But any living space adjacent to the outdoors or, say, a transitional space such as a garage ...