Air barriers are primarily designed to control which type of flow in buildings?

Air barriers are primarily designed to control airflow within buildings. This is essential for maintaining the building's energy efficiency and indoor air quality. By effectively managing the movement of air, air barriers help prevent unwanted drafts, minimize heat loss in the winter and heat gain in the summer, and reduce the infiltration of pollutants and moisture, which can lead to mold growth and structural damage.

While moisture flow is an important consideration in building design and can be influenced by airflow, air barriers specifically target the movement of air to enhance the overall environmental performance of the building envelope. Sound flow and thermal flow are also significant factors but are not the primary focus of air barriers. Sound control typically involves different materials and construction techniques, while thermal flow is managed through insulation rather than by air barriers alone. Therefore, the emphasis on controlling airflow distinguishes the function of air barriers in building construction and efficiency.