Winter is upon us, and insulation is on the minds of many homeowners right now. With most American households seeing a rise in energy bills at this time of year, and of course, wanting to maximize home comfort, HVAC contractors get a lot of questions about heating efficiency during this time. Attic insulation is an important part of winterizing a home and increasing its warmth.
Energystar.gov estimates that 9 out of 10 attics are under-insulated. When you think about how cold air sinks and warmer air rises, it makes sense that your attic insulation is one of the first places to look if your heating bills are high and your home feels drafty and cold. Insulation can either be added by a professional contractor, or on a do-it-yourself basis. Be sure never to cover recessed lighting or vents with insulation. For more tips on laying your own attic insulation, see here.
There are three main types of attic insulation: roll-on, blown-in, and spray foam. Before adding any type of insulation, be sure to plug or seal any areas of air leakage. Putting insulation over a hole or crack in the attic space will compromise its performance.
- Roll-on insulation: This is generally the easiest type of insulation to put in yourself, but it isn’t necessarily the most efficient. Rolls of this kind of insulation usually come in fiberglass material. Rolls are pre-cut and don’t require special machinery to install. Roll-on installation is also good for covering large or long areas of the attic, but the downside is that it doesn’t conform perfectly to irregularly-shaped areas.
- Blown-in: This form of insulation comes in small pieces, which makes it the best choice for filling in gaps, small spaces, and difficult-to-reach areas. It is applied with a machine that blows the material--usually cellulose or fiberglass--into the attic space through a large hose. It can also be applied over existing insulation.
- Spray foam: Spray foam can be the warmest option if applied correctly, but it can also be the most expensive. If applied too thick or too thin, spray foam insulation isn’t as efficient as blown-in or roll-on. As the name implies, this form of insulation involves spraying a coating of foam directly to the ceiling and walls of the attic. Spray foam, however, is a great option for sealing around vents, doors, and other drafty spots.