Whether you're building a new home, buying an existing home or planning to upgrade your current home, from an energy efficiency standpoint it helps to understand which is the best insulation for homes.
Federal Trade Commission
If you are buying a new home and want to be sure the insulation is adequate or better, the Federal Trade Commission's home insulation rule requires new home sellers to supply the following information regarding insulation (in the contract):
- Type
- Thickness
- R-value
Along with new home sellers, building insulation contractors are also required to provide comparable information. Also, check your state or local building codes, because many of them have minimum home insulation requirements.
Home Financing and Insulation
If you're ready to build a new home, it's good to know that some government home financing programs require homes to meet the Model Energy Code.
R Value and the Best Insulation for Homes
If you're trying to create an energy efficient home, the best insulation for homes has a higher R value. This rating is a way to measure the insulation's ability to resist heat flow. When you buy your insulation, base your decision on the R value rather than how much it weighs or how thick it is, because two insulations can be different in thickness and still have the same R value. This means that their ability to insulate is equal. Each type of house insulation has a different R value. Here are some of the best insulation for homes and their R value:
- Loose fill Cellulose Insulation - R value equals 3.70 per inch
- Loose fill Fiberglass Insulation - R value equals 3.14 per inch
- Loose fill Expanded Polystyrene - R value equals 4.00 per inch
Types of Insulation
After you decide what areas require insulation along with what R value is needed, you'll have to figure out which type to buy. In some cases, certain insulation must be installed by a professional, while others can be installed by a do-it-yourselfer.
Loose Fill Insulation
As you can tell by the name, loose fill insulation's clearest difference is its form. This insulation is produced as one of the following:
- Shreds
- Granules
- Nodules
Particles are small and fluffy and conform to the spaces where they are installed by being blown into the space with special equipment.
Benefits of Loose Fill Insulation
- Environmentally positive - made from recycled waste materials.
- Added chemicals provide resistance to fire and insects.
- Well suited for difficult to reach and irregularly shaped spaces.
- Can be installed in enclosed areas such as walls.
- Can be installed in open areas like attics.
Batt and Blanket Insulation
Batt insulation, also known as blanket insulation, comes in batts or rolls. This is the most common insulation and is most often made of fiberglass. Batt insulation can also be purchased in other fibers including:
- Mineral (rock and slag)
- Plastic
- Natural (cotton or sheep's wool)
If you plan to install batt insulation, take note that the R value will depend a lot on proper installation. Consider having a certified insulation installer come and do the work to be sure you'll get the maximum efficiency from your insulation.
When to Use a Vapor Barrier
As you plan to install insulation to protect your home from energy loss, keeping the R value high is important, but a big threat to the R value is water. If moisture seeps into your insulation, it automatically lowers the R value because once it gets in, moisture weighs down the insulation, which leaves gaps and bare spots.
One solution to this problem is to also install a vapor barrier. However, a vapor barrier is not really necessary where temperatures typically stay above freezing. If you aren't sure if you should install a vapor barrier, check with your local home improvement store or building supply for recommendations.
Note that batt and roll insulation is manufactured with a vapor barrier attached, but moisture leakage can still happen where the facings meet. This problem can be minimized if you take the time to staple the facings to the front of the studs rather than pressing the insulation into place. For best results, install a 4mil or thicker plastic tarp over the entire framed wall before tacking up the drywall.
