Hello there. I have an FD60 door to a boiler room which is due to be upgraded. Will a 15mm combined intumescent/cold smoke strip be sufficient or would a 20mm be preferable?

Kind Regards,

Brian

Combined Intumescent and Smoke Seals are designed to provide additional protection to prevent the passage of cold smoke. Does your FRA require FD60s or FD60 because if it is the latter you do not require cold smoke seals however In some circumstances, smoke seals are a Building Regulation requirement.  

Uninterrupted intumescent strips should be fitted into the frame or lining, where possible. If this cannot be achieved, the intumescent seals may be fitted into the door edge. The recommended seal size for most modern 30 minute doors, other than doorsets, is 15mm X 4mm. The recommended seal size for most modern 60 minute fire doors is 20mm X 4mm, or 2 No. 10mmX4mm.