What is the primary purpose of an air barrier?

The primary purpose of an air barrier is to control air movement and reduce energy loss in buildings. Air barriers are essential components within the building envelope, designed to prevent uncontrolled air infiltration and exfiltration. When air can move freely through a building, it leads to a significant amount of energy loss, as conditioned air escapes and unconditioned air enters, making heating and cooling systems work harder and leading to increased energy costs.

By effectively managing air flow, air barriers help maintain indoor temperature and humidity levels, thereby enhancing energy efficiency. This contributes to overall occupant comfort and reduces the environmental impact through decreased energy consumption.

The other options focus on functions that are secondary or related to the benefits of air barriers but do not capture their primary role. While insulation, aesthetics, and soundproofing are important aspects of building design, the main goal of an air barrier directly pertains to controlling air movement and minimizing energy losses.