How to Air Seal an Attic

July 8, 2013

Tiny air leaks into uninsulated or under-insulated attics are a big cause of heat loss for many Texas homes. As a result, homeowners suffer from loss of conditioned air and higher energy bills. Air sealing your attic with insulation, caulk, and spray foam is the most effective way to improve the energy efficiency of your home and its overall comfort. Here’s how to air seal an attic.

Advice for working in your attic

Plan – Plan your project and get together all the materials and tools you’ll need for the job.
Be ready to get dirty – Working with insulation in the attic is a dirty job, so wear lightweight, disposable overalls, knee pads, gloves and hat to keep the insulation off your skin and out of your hair.
Safety – Be safe. Only work 15 to 20 minutes at time, stay hydrated and use a government-approved particulate respirator or double strap dust mask to keep from inhaling hazardous material.

Tips on how to seal an attic

Create a sketch of your home’s floor plan. Highlight dropped soffits, slanted ceilings above staircases and other areas with dropped ceilings. Also, highlight the main plumbing stack, furnace flue and other ductwork.
Pressurize your home by placing a box fan in a window so it’s blowing air into your home. Make an airtight seal around the fan by taping cardboard around the fan. Close all windows and doors, and go into the attic closing the hatch behind you. You should be able to begin to feel the leaks.
Plug the large, obvious holes first and replace dirty insulation with clean insulation.
Seal all joists with bagged insulation.
To seal your furnace flue and ductwork you’ll want to contact your HVAC professional.
Use caulk and spray foam for the small holes.
Seal your hatch.
Check for backdrafting by installing a carbon monoxide detector on each floor. Consult with your HVAC professional about potential hazards of an airtight home.

To learn more about how to air seal an attic, contact JD’s A/C. For more than 30 years, we’ve proudly served the residents of Longview and the surrounding communities.