How to Blow Insulation Into a Recessed Attic

Climb into the attic via the ladder, and place wooden planks atop the ceiling rafters. Place these in such a way that you can access the whole attic area. If you step between the rafters, you could fall through the roof. The wooden planks provide the walking area needed for completing the project.

Check the amount of insulation needed for your region, using the government's Oak Ridge Laboratory "R-Value Recommendations by Zip Code," online tool (see Resources).

Set up the portable lights so that you can see what you’re doing in the attic.

Prepare the recessed attic before blowing in the insulation. This means locating any recessed light fixtures and ensuring they have a metal cover or wooden frame around them for protection. These elements require a minimum of 3 inches of space to prevent fires caused by the light’s heat against the insulation. Install a block of wood between the rafters on either side of the recessed canister. Some recessed light fixtures have a metal canister with a top on them for this purpose. These will be listed as Underwriters Laboratory approved and marked, “Recessed Fixture Type LC.” These fixtures dissipate the heat appropriately and can be used next to insulation.

Seal all attic vents with caulking, including the tops of interior walls where they abut the attic and around plumbing vent pipes and chimneys. Use high-temperature caulk around the chimney area and regular caulk elsewhere.

Apply rubber-backed insulation to the attic door or cover with an adhesive so it stays in place. Place a 4-inch frame of wood around the opening to keep blown-in insulation from tumbling through the attic door or access panel when it's opened.

Verify all electrical wiring has the appropriate covering. Insulation that comes into contact with bare electrical wires could ignite.

Check that all eave vents have the proper baffling around them before blowing in the insulation. Eave vents require a minimum of 2 1/2 inches of free air clearance.

Prevent all exhaust fans and motors in the attic from coming into contact with the blown-in insulation. Build or set a baffle around these to keep insulation away.

Set measuring sticks in strategic locations according to the loose-fill depth requirements for the recommended R-value for your region.

Feed the insulation blower at a consistent rate while blowing the insulation into the attic. This might require the assistance of a helper so that you don't have to stop what you're doing during this process.

Start at the farthest corners of the attic and work back toward the attic access point. Cover the spaces between the joists a little higher than the measuring sticks placed in the attic to allow for loose-fill insulation settling.

Pour insulation into areas requiring more precision, such as around eave vents. Reduce the insulation at these locations to ensure proper air clearance.

Use the rake or broom to level insulation evenly in the spaces.