Intumescent fire door strips swell if there is a fire and stop the spread of fire through the gaps at the top and sides of fire doors. If the passage of cold smoke needs to be stopped as well you need to fit seals with an additional brush seal. Our rebated or surface-mounted intumescent fire door seals resist fire for 30 or 60 minutes (suitable for FD30 or FD60 fire doors). All our fire door seals are available for single and double fire doors. The seals can be fitted in the frame or the door leaf.