An Air Barrier refers to a system or combination of materials, components, and techniques that are designed and installed to restrict the uncontrolled movement of air into or out of a building. It serves as a continuous and unbroken layer within the building envelope, helping to enhance energy efficiency, indoor comfort, and indoor air quality.
The primary function of an air barrier is to minimise air leakage, which can result in significant energy losses, increased heating and cooling demands, and compromised thermal comfort. It prevents the infiltration of outdoor air, which can introduce pollutants, allergens, and moisture into the building, while also preventing conditioned air from escaping.
An effective air barrier system typically includes a combination of air barrier materials, such as membranes, sheathing, sealants, tapes, and gaskets. These materials are strategically applied and integrated at various building envelope assemblies, including walls, roofs, floors, windows, and doors.
Proper installation and detailing of the air barrier system are crucial to ensure its effectiveness. Seams, joints, penetrations, and transitions must be carefully sealed to create a continuous and airtight barrier. Regular inspections, quality control measures, and airtightness testing may be conducted to verify the performance of the air barrier system.
By implementing an air barrier system, building owners and professionals can improve energy efficiency, reduce heating and cooling costs, enhance indoor comfort by minimising draughts and temperature fluctuations, and promote better indoor air quality by controlling the entry of pollutants and moisture.