Why Does a Fire Door Work Sometimes but Not Others?

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. Intermittent faults are evidence too A fire door that closes perfectly in the morning, struggles later and then works again is telling you something. A fixed mechanical defect can be intermittent, but changing conditions should also be considered. Record when it happens Note the time, whether nearby doors are open, heating or ventilation conditions, weather…