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Which Insulation Do I Need?

The type of insulation you need depends on where the insulation will be installed, what R-values are needed, and your budget.

Poly-encapsulated Insulation

Poly-encapsulated insulation, such as Comfort Therm© insulation, is entirely wrapped in plastic. This allows for a more comfortable installation with less itch and dust. This type of insulation also has superior acoustic properties. The poly-faced vapor retarder is twice as resistant to moisture as Kraft-faced products.

Faced Insulation

This is insulation with a facing already attached to it. Facing acts as a vapor retarder and is commonly made from Kraft paper or foil, depending on the intended application. In addition to its thermal and acoustical properties, faced insulation is ideal for moisture control on exterior walls.

The type of insulation you need depends on where the insulation will be installed, what R-values are needed, and your budget.

Unfaced Insulation

Unfaced insulation has no facing attached to it. This type of insulation is effective when controlling unwanted noise in internal walls and to assist with moisture control. Where vapor control is required, a separate vapor retarder can be used.

Blown-in Insulation

This type of insulation consists of loose-fill material that is blown into position through a hose connected to a blowing machine. This type of insulation is made for nonconforming spaces and hard-to-reach areas, like corners, edges and around framing and does not settle or decay. The insulation can be made from a variety of materials such as fiber glass and cellulose.

Should I Use Rolls or Batts?

Rolls are long strips of insulation rolled up and they require measuring and cutting. In general, rolls are best for covering large open area like attics and crawl spaces. Batts are pre-cut lengths of insulation cut for 8-ft. and 9-ft. walls. Batts are best for insulating interior and exterior walls. For standard size walls or crawl spaces, the pre-cut batts make the job go faster with fewer hassles. If you are insulating an entire house, it's most convenient to use a combination of batts and rolls.

What is a Vapor Retarder?

Moisture in the air in the form of vapor is transferred along with heat. This is especially common in humid environments and in certain areas inside a home - such as bathrooms, kitchens and laundry rooms. When moisture vapor becomes trapped, mold and mildew growth can result. Vapor retarders keep the moisture in the air in your house from condensing in the insulated cavities.

Whether or not you need a vapor retarder depends on local building codes and your climate. Generally, in hot, humid areas using a vapor retarder is not recommended. In mixed climate areas, the vapor retarder is optional depending on the total design of a building. In cold climates, a vapor retarder is almost always needed.

The facing on faced insulation acts as a vapor retarder. If you need a vapor retarder and your insulation is unfaced, you must cover it with a polyethylene film.

Installing Insulation
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