Attic Insulation Over Blown In

Most attics are insulated with blown in loose cellulose r 3 5 per inch blown in loose fiberglass r 2 5 per inch or fiberglass batts r 3 2 per inch.

Attic insulation over blown in.

Blowing in insulation is a messy prospect and you ll need to wear a dust mask protective eyewear. The cost of blown in insulation is determined by which material you decide on the r value needed and the space of your attic. Insulation efficiently fills gaps. Never stand on joists.

The type of material you use is up to you. Batt insulation is available at home centers and lumberyards. Blown in insulation flows down around wall studs. If you choose loose fill insulation you ll need to rent a machine to install it.

For an r value between 38 and 49 the average person spends about 1 50 each square foot. Position the new vent chute so the. Fiberglass is just that thin fibers of glass that trap air. This calculator is to be used as an estimating tool only.

Batt or rolled insulation or blown loose fill insulation fiberglass or cellulose can be installed on top of old insulation. Pull the existing insulation away from the roof. Blown in insulation in the attic seal attic bypasses. Batt insulation take time to read this column.

Always cover the tops of the ceiling joists to make sure the insulation is deep enough to reach your target r value and to prevent thermal bridging the heat loss that occurs through the wood framing. Cellulose is recycled newsprint treated with a fire retardant. Someone needs to load the bags of insulation into the blower which will remain on the floor below. Insulation should be rolled out perpendicular to the joists and unfaced rolls should be used.

Blown in fiberglass is considered flame resistant. If you stand on joists in the. Pull back the existing insulation and use expanding spray foam the fire blocking type to seal any. The vapor retarder on top of or between layers of insulation can trap moisture.

Install or repair vent chutes. Loose fill blown in insulation is best for tight spaces or if your attic already has a layer of insulation that just needs to be topped off. We include blown in attic insulation pros and cons but we can t recommend blown in fiberglass or cellulose as your best insulating choice. Don t forget to factor in whether you will be renting a blow machine or hiring someone to do it for you.

Click the button to calculate the depth in inches and pounds of total insulation required for this job. Any existing batt or roll insulation in the attic should have the facing against the attic drywall floor or no facing at all. Before choosing blown vs. Recruit a helper.

Input length width and desired r value of the area to be insulated. Blown in insulation requires a professional.