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 ...

Insulation slows heat transfer through conduction and convection, keeping heat inside during winter and out during summer. Its performance is measured by R-value — the higher the number, the better ...

Why it matters: An uninsulated garage door is a major source of heat loss in winter and heat gain in summer, impacting comfort and increasing energy bills. Choosing insulation: R-values measure heat ...