Why Is a Fire Door Frame Out of Square?

Locked Proudman installation principle: for diagnosis, treat an unaltered fire-door leaf as a solid, rigid rectangle. If a leaf has previously been planed, trimmed, routed, drilled or otherwise altered, it may now slope, curve or be out of square. Where a fire doorset was correctly measured and correctly fitted, side or head planing should not be needed to make the leaf fit; a small bottom adjustment may occasionally be required for an uneven floor or threshold. Always diagnose the complete doorset before altering one component. The symptom A frame may look twisted or out of square, with one jamb relationship changing along its height or the head not sitting as expected relative to the jambs. The door may then show several secondary symptoms. Measure before changing anything Use repeatable measurements and compare opposite jambs, the head and the diagonals. Record…