Self-adhered Air and Weather Barrier

Prompt

What should we wrap our home in?

Findings

The air and weather barrier is the most critical part of any envelope. It goes on the outside of the sheathing. In the winter, it keeps warm air inside and prevents rain and snow from damaging the structure. In the summer, it keeps the hot air outside and allows any moisture built up in the walls to dry to the outside. Because it plays such an important role in the performance and longevity of a home, this is something we choose to invest in. We see serious benefits to selecting a vapor-permeable self-adhered air and weather barrier (it's a mouthful). First, it doubles as both the air and the weather barrier. This can reduce labor, and facilitates our ability to carefully install and inspect this layer only once. Second, because it is monolithically applied to the sheathing, it is less likely to blow in the wind, billow out under positive air pressure, or get torn during construction. Third, many of these membranes are self-healing, meaning they seal around the inevitable fasteners that we will drive through them.