Definition
Fire Resistance Rating
A fire resistance rating is the tested period — typically 30, 60, 90, or 120 minutes — for which a building element maintains load-bearing capacity (R), fire integrity (E), and thermal insulation (I) when exposed to a standardised fire. Ratings are specified by Approved Document B and BS 9999 for walls, floors, doors, and structural columns depending on building type, height, and occupancy.
Terms mentioned in this definition
