Backdraught Dampers

BSB’s Backdraught Dampers are designed to allow airflow in one direction only, automatically closing when airflow stops or reverses. This prevents backflow, protecting indoor environments from cold air ingress, odours, pollutants, and pressure imbalance within ventilation systems.

Commonly installed within ducted ventilation systems, these dampers are ideal for residential, commercial, and industrial applications, including extract fans and mechanical ventilation systems. They operate automatically using gravity, spring-loaded, or pressure-activated mechanisms, requiring no external power.

Key benefits include:

• Prevention of reverse airflow
• Improved ventilation efficiency
• Reduced heat loss
• Elimination of draughts
• Protection against external contaminants
• Low-maintenance operation
• Compatibility with circular and rectangular ductwork

Manufactured from durable materials, BSB’s Backdraught Dampers is built for reliable long-term performance and easy installation within new or existing ventilation systems

A Backdraught Damper is a mechanical device that allows air to flow in one direction while preventing reverse airflow.

It prevents cold air, odours, and pollutants from entering the building through ventilation ducts.

They are installed in ducting, behind extract fans, or within ventilation systems.

No — they operate automatically using air pressure or gravity.

Yes — they are suitable for domestic, commercial, and industrial installations.

When correctly sized and installed, they have minimal impact on airflow efficiency

Maintenance is minimal, usually limited to periodic inspection and cleaning if required

Yes — they are available in a range of diameters and duct formats to suit various systems.