What a fire-rated board actually rates — and the three details inspectors check.

A fire-rated board does not carry a rating on its own. The rating belongs to a tested system — the board, its fixings, its joints, and the substrate behind it. Change the system and the rating no longer applies.

Inspectors check three things first: fixing centres, joint treatment, and how penetrations through the board are sealed. A correctly rated board with the wrong fixings fails as surely as the wrong board.

We specify the board as a system and document each of those three details before close-up. The rating then describes what was actually built.