How to Hang Airtight Drywall
Drywall can stop air leaks when it's installed with caulk, foam, and adhesive.
Synopsis: If you want to make your house more energy efficient, the first thing to do is stop air leaks. Because drywall is great at stopping air, it can be part of a house’s air barrier when installed using the airtight-drywall approach. This approach, described in this article by contributor Myron R. Ferguson, makes use of caulks, sealants, canned foam, and gaskets to seal the seams between sheets and to stop airflow through holes cut in the drywall. Ferguson begins an airtight-drywall job by applying flexible caulk to all gaps in the framing and by sealing electrical boxes. He then hangs the ceiling, making sure to seal the holes he cuts out for junction boxes and light fixtures with caulk, and to seal the perimeter between the framing and the drywall with canned foam. Finally, he hangs the walls. Window openings are sealed with caulk and polyurethane construction adhesive, large gaps with canned foam, and small gaps with caulk. Ferguson demonstrated his technique at FHB‘s Project House, and this article includes a drawing that shows the exact locations where he applied caulk, foam, and construction adhesive.
Stopping air leaks is the single most important part of making a house more energy efficient. You can stop air on the outside with plywood, housewrap, and tape, but the best air barrier is a system that incorporates the whole wall or roof assembly.
As it turns out, drywall is excellent at stopping air. If you doubt that, try to blow through it. The weak spots are the seams between sheets and the holes that you have to cut for windows, doors, electrical boxes, and can lights. The process for installing drywall as an air barrier is called the airtight-drywall approach and it relies on caulks, sealants, canned foam, and gaskets to…