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.

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. The type of material you use is up to you. This calculator is to be used as an estimating tool only. Insulation efficiently fills gaps.

Recruit a helper. Cellulose is recycled newsprint treated with a fire retardant. Attic insulation is accomplished with either fiberglass blankets batt or blown in insulation. Blown in insulation in the attic seal attic bypasses.

Pull the existing insulation away from the roof. Never stand on joists. Install or repair vent chutes. Batt or rolled insulation or blown loose fill insulation fiberglass or cellulose can be installed on top of old insulation.

Click the button to calculate the depth in inches and pounds of total insulation required for this job. Position the new vent chute so the. Batt insulation take time to read this column. If you choose loose fill insulation you ll need to rent a machine to install it.

Blown in insulation flows down around wall studs. Don t forget to factor in whether you will be renting a blow machine or hiring someone to do it for you. Blown in fiberglass is considered flame resistant. Pull back the existing insulation and use expanding spray foam the fire blocking type to seal any.

Blowing in insulation is a messy prospect and you ll need to wear a dust mask protective eyewear. Batt insulation is available at home centers and lumberyards. Before choosing blown vs. If you stand on joists in the.

Materials can be layered for added protection. The cost of blown in insulation is determined by which material you decide on the r value needed and the space of your attic. Work from the perimeter of the attic toward the door or hatch so that you don t trample all over the insulation you just put in. Insulation should be rolled out perpendicular to the joists and unfaced rolls should be used.

We include blown in attic insulation pros and cons but we can t recommend blown in fiberglass or cellulose as your best insulating choice. The vapor retarder on top of or between layers of insulation can trap moisture. Someone needs to load the bags of insulation into the blower which will remain on the floor below. For an r value between 38 and 49 the average person spends about 1 50 each square foot.

Blown in insulation requires a professional. Fiberglass is just that thin fibers of glass that trap air.