Internal Grilles and Airbrick Cowls

Installation Advice

Internal grilles should be positioned over the internal opening of the cavity sleeve and fixed to the wall using screws and wall plugs
External cowls are positioned over the face of the airbrick and fixed to the wall using screws and wall plugs, the opening of the cowl should face towards the ground
Never block or restrict the flow of air through these ventilators. The louvre grilles have no insect screen fitted, this is in order to comply with British Gas requirements
Use open louvre grills when ventilating a gas or heat producing appliance, never use hit & miss grilles in such situations