Our Products
Tube/Twin/Canopy FansDemand Control Ventilation Domestic FansCommercial FansIndustrial FansDomestic Vent & Heat RecoveryAir Handling & Heat Recovery UnitsPlastic Ducting & AncillariesGrilles & DiffusersChilled BeamsFire / Smoke Dampers & VCD'sDuct Heaters & CoolersUnit Heaters & DehumidifiersAir Curtains LPHW & ElectricFan Coils UnitsVAV's & CAV'sFume Extract UnitsSilencersControlsCooker Hoods

Fire / Smoke Dampers & VCD's

Backdrsught Dampers

Backdraught Dampers

The BD Series Backdraught Damper is self-opening subject to air velocity and is designed to restrict air back flow.
The damper can be fitted to partitions or brick walls, on plenums or duct mounted.


• Standard case construction is galvanised mild steel
• Extruded aluminium blades
• Flange or spigot casing options
• Infinite sizing capability
• Unique blade end seal and stop
• Variable blade position for alternate airflow direction

Specifications & Tests
• Unless otherwise stated, all models are suitable for classes A & B of DW144.
• Conforms to HVCA specification DW144 classes A and B, and Eurovent as relevant.
• Independent performance tests for pressure drop. Test report 165 refers.


Blade Details

Standard extruded aluminium blade
The nominal 60mm wide standard extruded aluminium blades are fitted onto 6.25mm diameter spindles, complete with blade edge brush seal fitted as standard.
All blades are fitted for parallel operation only.

Blades are linked with a precise linkage, alleviating movement and subsequent rattling of individual blades. Refer to pressure drop figures for suitability (see download page).

Avoid use of dampers in extremely turbulent duct conditions. Although blade linkages will stabilise blades in most conditions, abnormal circumstances may cause damper malfunction.