Why Does a Fire Door Lock or Bolt Stick?

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 The latch or bolt is difficult to retract, does not project fully, sticks in one position, or works with the door open but not when the door is shut. Test it open versus shut This is one of the most useful first distinctions. Free movement with the door open points the investigation differently…