Fire Regulations require intumescent seals to be rebated into the edge of fire doors to provide passive fire protection. Upon exposure to heat in the event of a fire, the intumescent material swells up to seal the gap between door and frame, this dramatically slows down the spread of the fire from room to room, giving precious time for evacuation and rescue. Depending upon the door and the application, these may be 30 minute or 60 minute fire seals, and they may be just fire seals or fire & smoke, which incorporate a brush or rubberised strip which prevents smoke from passing through the gap. If you’re not sure which ones you need, check with your Fire Officer or Building Control Officer. Doorstuff supplies 3 sizes of each type, available in both white and brown, prices start at £1.17 per 2100mm strip.