Fire Dampers – Duct SleevesDS MVHR 18
Designed to protect ventilation duct that passes through fire rated walls made from block, brick, concrete or hollow plasterboard.
A reinforced covering contains intumescent material that expands inwards, crushing PVC duct in the heat of a fire.
They can be easily cut with a sharp knife and should be installed level with the surrounding wall.
Horizontal fire damper installation:
A surface mounted circular metal unit for use around PVC or steel duct that pass through fire rated ceilings or walls.
The unit consists of a hinged, two part metal collar containing intumescent material with a quick release pin for easy fitting around pipes.
Fixing lugs are supplied for simple attachment to block, brick concrete or plasterboard.
BS476 PARTS 20 & 22 (1987):
Vertical fire damper installation: