What is one type of air barrier material?

Drywall is a type of air barrier material because it can help to reduce the movement of air through wall assemblies when properly installed. It serves as a solid, continuous layer that can mitigate the flow of air, thus contributing to improved energy efficiency in a building. When used in conjunction with appropriate sealing methods, drywall can effectively help to prevent unwanted air leakage, which is essential in maintaining indoor climate control and reducing energy costs.

Glass, sponge, and clay do not serve as effective air barriers. Glass typically functions as a window material, sponge absorbs moisture rather than blocking air flow, and clay is not typically used as a construction material for air barrier systems. Therefore, drywall is the most suitable option among the choices provided for serving as a reliable air barrier in building construction.