Your home's location, budget, and the type of insulation you’re using are just a few of the factors that can help you choose the right insulation. For example, blown-in insulation is typically used in attic spaces, while batts and rolls are ideal for floors and walls. Blown-in insulation is usually a good option if you're adding more insulation to an area that already has some, but not enough.

Yes, basement insulation needs a vapor barrier due to its susceptibility to moisture seeping in from the outside of the house. You should install a moisture barrier before you install insulation or purchase insulation that comes prebuilt with a moisture barrier to avoid water damage in your insulation and costly mold and water remediation expenses. 

Insulating a detached garage won't reduce your home's heating or cooling bills—and insulating an attached garage will only have a small effect on your home's energy efficiency. However, insulating an attached garage can reduce the transfer of heating and cooling to and from the outdoors, which can reduce the amount of energy your home needs to stay comfortable. Also, having an insulated garage is just more pleasant. Balance the cost of insulating your garage with how you'll use the space to determine if the project is worth it.

According to a report from Energy.gov, radiant barrier installations can save between 5% and 10% on your energy bill each month that your HVAC cooling is in operation. That fact can mean savings of up to more than $325 per year for homes that experience frequent direct sunlight and high summer temperatures.