The top and bottom plates of exterior walls, all exterior room corners, and the perimeter of window and door openings need sealant—preferably a flexible one. (Adapted from BSC Information Sheet 401: Air Barriers—Airtight Drywall Approach.)

Air leaks through the building shell can have a significant effect on a home's durability, energy use, and indoor air quality. You've heard this before, or at least I hope you have by now. But I'm a drywall contractor. What do air leaks have to do with my work? Well, I believe that drywall can be an important part of the air barrier of an enclosure. Once I recognized this, it changed the way I do my work.Not Just One Air BarrierFor most houses, I don't think it makes sense to consider the air barrier as a single plane. It's...