When is a fire damper required?

Fire dampers are required wherever a duct penetrates a fire-separating element (compartment wall or floor) to maintain the fire resistance of that element. This is required by Approved Document B and BS 9999. Without a damper, fire and smoke can spread through the ductwork system.

How often do fire dampers need testing?

Fire dampers should be tested annually in accordance with BS 9999 and the Regulatory Reform (Fire Safety) Order 2005. The test confirms the damper closes fully and resets correctly. Records must be kept. Motorised dampers may need more frequent testing as part of the BMS system.

What is the difference between fire dampers and smoke dampers?

Fire dampers close when they detect heat (via fusible link or intumescent material) to prevent fire spread. Smoke dampers close when they detect smoke (via detector signal) to prevent smoke spread. Combined smoke/fire dampers provide both functions and are needed where smoke control is critical.

Do fire dampers need access panels?

Yes, all fire dampers must have accessible inspection and maintenance hatches. BS 9999 requires that dampers can be inspected, tested and maintained. Access panels should be at least 300mm x 300mm and located adjacent to the damper on the duct.

How much do fire dampers cost in the UK?

Basic mechanical fire dampers cost £80-£150 supply. Motorised fire dampers with actuators cost £250-£450. Combined smoke/fire dampers cost £300-£500+. Installation adds £80-£200 per damper. Annual testing costs approximately £25-£45 per damper.

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Fire Damper Calculator

Calculate fire damper quantities, sizes and costs for ductwork penetrations through fire compartment walls and floors. Includes annual testing cost estimates.

Damper Type

Mechanical is most common

Duct Shape

Matches ductwork type

Duct Diameter

Internal duct dimension

Number of Dampers

Total dampers required

Price per Damper

Supply cost per unit

How We Calculate This

This calculator estimates fire damper costs based on type, size and quantity.

The formula

Total = (Supply × Qty) + Installation + Access panels

Supply cost varies by type, size and fire rating
Installation: £80-180 per damper
Access panels: ~£45 each (mandatory)
Annual testing: ~£35 per damper

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.