Fire Door Strips & Seals

Intumescent Strips and Smoke Seals

Intumescent strips and smoke seals are what let a fire door do its job in the gap around the leaf. Under normal conditions they sit discreetly in a groove in the door edge or the frame, but in a fire the intumescent material expands rapidly to close that gap and hold back flames, while a smoke seal, usually a brush or fin, limits the cold smoke that spreads before things get hot. Fitted correctly they are part of the complete, tested doorset, not an optional extra. Every fire door needs the right seals to perform to its FD30 or FD60 rating.

Strips, seals and combined types

There are a few types worth knowing. A plain intumescent strip handles flame and heat, while a combined intumescent strip with a brush or fin adds smoke sealing in a single fitting, which is what most modern fire doors call for. They come in standard lengths and widths to suit the door and are set into a routed groove in the edge of the leaf or the frame. Choosing the right size and type for your door and its rating is the important part.

Door seals for draught and sound

The range also includes general door seals, such as the compression seals that quieten a door and cut draughts. These are about comfort rather than fire, so they are not fire rated, but they are a useful finishing touch on any door where you want a softer close and less noise. It is worth keeping the two purposes clear: intumescent strips and smoke seals for fire, compression seals for draught and sound.

Complete the fire doorset

Seals work alongside the rest of the set. Set the door into a rated fire door frame or lining, hang it on the correct fire door hinges, and choose the leaf itself from our oak fire doors. Fitted together and to the door manufacturer's instructions, the door, frame, seals and hinges make up the tested doorset that holds its rating.