Hepworth Terracotta airbricks allow the free movement of air to ventilate buildings. Terracotta airbricks can complement the external finish of a property and will weather well with the surrounding brickwork. Terracotta cavity liner provide a bridging duct across cavity walls Used in conjunction with 215x215mm airbricks Feature 3 200mm long Suitable for new build and refurbishment projects. Clay Air Bricks are used to ensure air circulation between floors and cavity. This airflow prevents the intrusion of damp and rot within internal "voids" and gives your projects added protection. Resistant to the effects of the "Thaw-Freeze" cycle the bricks avoid the damage this often causes materials.