Air Seal Attic Top Plate

The room most likely has drywall walls and ceiling that meet flush together.

Air seal attic top plate.

I have used rigid foam tightly fit over the top plate between the ceiling joists and extending in a bit over the drywall. Save money by adding blown in insulation to your attic. Top plates are a focal point in almost every energy audit and air sealing job we perform. If your home has this kind of air leakage it s easy to find.

Top plates are where a variety of building materials come together. To fix it you just fill the gap with caulk or spray foam. It s usually the hardest place to air seal because the cramped space underneath the eaves where the roof rafters rest on the outer wall makes it hard to move your hands and head. These are often found in the top plate drop soffits and chases and the volume of conditioned air that escapes through them is equivalent to leaving a window wide open the year round.

Air sealing the attic perimeter. What does air sealing top plates in an attic mean. We seal the gap between the top plate and the drywall installed on the partition wall because air can leak between the drywall on the wall and the top plate. The nailer above the crack is not airtight so the nailer doesn t prevent air which is under positive pressure with respect to the attic from entering the attic.

With air chutes in each rafter space you can fill the void between the rigid foam and air chute for an airtight high r assembly. A big culprit for air leakage in a home is through holes in the floor of the attic. Think about the rooms right below the attic. Air seal drywall to top plates at all attic wall interfaces to minimize air leakage.

Just go up in the attic pull back the insulation and find the top plates. You will also want to get air chutes in place from this vantage point. If you have soffits that would be the best access for sealing over top plates. Install drywall then seal the seam from the attic side with caulk foam or drywall adhesive but not other construction adhesives.

Between the drywall and the top plate of the wall we ve got a few different choices of materials we can use to seal up. Air sealing the wall plate around the perimeter of your attic blocks air from escaping around the outer edges of your home. The photo at left shows a typical one flush drywall on one side and a big gap on the other. Before installing drywall install caulk or other sealant or a foam gasket to the face of the top plate then install the drywall.