Internal, fire & entrance doors

How does Internal, fire & entrance doors work, step by step?

1. 1

   Step 1: Work from the door schedule and the ironmongery schedule together

   The door schedule identifies every door on the project - location, size, handing, leaf type, glazing, finish, and what the door is required to achieve. The ironmongery schedule lists what goes on each one: hinges, lock or latch, handles, closer, seals, signage, and any access control. The two are read together, because on a performance door the ironmongery is part of the assembly rather than an accessory to it. Both are issued before ordering, and the designer and the fire engineer set the requirements they record. Substituting an item because it arrived late or costs less is a change to the assembly, and on any performance door it is a change that has to go back to the designer.

2. 2

   Step 2: Decide doorsets or site assembly and order to the survey

   Wherever the door has a performance requirement, the usual route is a complete doorset supplied as the tested combination. Where doors are assembled on site, the specification defines each component and its compatibility with the others. Openings are surveyed as built before ordering, exactly as for windows, because structural openings vary and a doorset is manufactured to a size. The survey records opening dimensions, squareness, plumb, floor level across the opening and the finished floor build up, since a door set to the wrong floor datum will either bind on the finish or leave a gap under it that nobody wanted.

3. 3

   Step 3: Store and handle the leaves properly

   Door leaves are damaged and distorted more often in storage than in installation. They are stored flat and level, off the floor, clear of damp, and in the building only once it is dry enough not to move them. Leaves are handled on edge by two people rather than dragged, and are kept in their protection until fitted. Performance doors carry identification that has to remain legible and intact, so protection is removed carefully and the identification is never cut off or overpainted. A leaf that has taken up a twist in storage will never hang correctly, and planing it to fit is not a repair.

4. 4

   Step 4: Fix the frame plumb, square and properly packed

   The frame is set into the opening, plumb on both jambs, square across the head and diagonals, and set to the correct position relative to the finished floor and the finished wall lines. It is packed solidly at the fixing points so the frame is supported rather than bridged, and fixed back to the structure using the fixings the specification requires for that assembly in that substrate. On a performance door the packing and the fixing arrangement are part of what was tested, and voids behind the frame, missing packing or an incorrect fixing type all change the assembly. Frames are re-checked for square after fixing, because tightening into unsupported packing pulls a frame out of true and every gap around the leaf then goes out with it.

5. 5

   Step 5: Hang the leaf and set the gaps

   The leaf is hung on the hinges the assembly specifies, fitted to the full depth of their housings with every screw in place - a missing screw in a hinge on a performance door is a defect, not a snag. The leaf is then set so the gaps around it are even and within what the assembly requires at head, jambs and threshold. The specification records those gap requirements; the installer works to them and measures rather than eyeballs. Gaps are the single most common failure found in fire door inspection, and they go wrong for a mundane reason - the frame was slightly out and the gap was allowed to take up the error.

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   Step 6: Fit the seals, the ironmongery and the glazing as specified

   Intumescent and smoke seals are fitted in the positions the assembly requires, continuous, fully seated in their grooves and unbroken at the corners, and not painted over. Ironmongery is fitted to the schedule and to the manufacturer instructions for that item on that door, with the correct fixings and no improvised cut outs. Where the door is glazed, the glass, the beads and the fixing of the beads are all part of the assembly and are installed as specified rather than as convenient. Any penetration through a leaf or frame that the assembly did not include - for a cable, a sign fixing or a vision panel added on site - is a change and is referred back rather than made good afterwards.

7. 7

   Step 7: Adjust the closer and prove the door in operation

   The closer is adjusted so the door closes fully and latches from any position it is likely to be left in, against the seals and against the pressure in the corridor. That is the whole point of a self closing door and it is the thing most often left unfinished, because adjusting a closer properly takes longer than fitting it. Doors on hold open devices, on access control or on any interface with the fire alarm are proved to release and close as intended. Every door is operated repeatedly and the latching is confirmed - a door that closes to within a few millimetres and stops is a door that does not work.

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   Step 8: Inspect, record and protect

   Performance doors are inspected against the schedule and the assembly requirements, and the inspection is recorded per door: identification present and legible, frame fixing and packing, gaps measured, seals continuous, ironmongery as scheduled, closer adjusted and latching proved. Photographs of the frame fixing and packing before the architrave goes on are worth more than any amount of later discussion, since that work is concealed for the life of the building. The records form part of the information handed to whoever will manage the building, because the doors will be inspected again in service and the original record is the baseline. Doors are then protected until handover, and damage to a performance door is repaired only in ways the assembly allows.