Transfer grilles — air circulation between rooms without ductwork

Transfer grilles solve a fundamental problem in residential mechanical ventilation: fresh air is supplied to bedrooms and living rooms, but must be able to flow to bathrooms and kitchens (where it is exhausted) without being blocked by closed doors. Without air transfer, a closed bedroom door creates negative pressure in the bedroom (where air is supplied but cannot leave) and positive pressure in the bathroom (where air is exhausted but insufficient can enter) — both disturb correct installation operation and can generate unpleasant door noises. Construction: anodised aluminium profiles with Λ-shaped blades (120° angle) allowing bidirectional air passage while blocking direct line of sight between rooms — visual privacy is maintained. Available for door mounting (cut-out in door panel) or wall mounting.