Upgrade existing purpose-designed and constructed British Standard fire door

Upgrade existing purpose-designed and constructed British Standard fire door

N.B. Where purpose-designed and constructed British Standard fire doors have been fitted in the past to an earlier 30 minute fire door specification, they may be brought up to current standards by carrying out the following works, but only if completely sound and undamaged. Where the door has suffered damage, has warped, or where letter box has been fitted, it may be possible to upgrade. If the frame has warped, split, twisted or has otherwise been damaged, or is no longer square, a new frame will be required. Where upgrading is to be considered, it will be necessary to inspect each door on site with the architraves removed prior to agreeing to upgrading. It will also be necessary to inspect during works and prior to re-fitting of the architraves.

Where existing doors are not of a purpose-designed fire door specification but are non-fire doors or are non-fire doors which have been “made up” to a fire-resisting standard by the sheeting of inner face or panel with fire-resistant boarding – they cannot be retained. New doors and frames will be required.

Carry out the following works to the door # specify position # Remove the architraves and if sound set aside for re-use. Examine the frame to determine whether sound, square and capable of retention. Square the frame as necessary and fill all voids with intumescent mastic or paste. Fill gaps between frame and wall/partition opening with intumescent mastic or paste. Where door leaf is binding with the frame , relieve door by removal of minimum amounts of timber equally from door and frame. Fill gaps greater than 4mm by fitting solid timber of equivalent density to door and frame respectively . The bottom edge of the door should be parallel to the floor finish so as not to bind and to leave a maximum gap of 10mm beneath the door when closed. The timber to be screwed and glued using non-thermally softening glue. Minimum permitted size of timber infill is 6mm. Fit a intimately fitted softwood or hardwood architrave, at least 15mm thick with a 15mm overlap onto both wall and door frame. On completion the door to be close fitting with frame (maximum gap 4mm) and effectively self-closing to engage the latch. It is recommended that an overhead hydraulic closer is used. Hang on three steel or brass hinges with hinge blade size of 75-100mm by 27-33mm. The doors or frames are to be fitted down both jambs and along the head with intumescent strips and cold smoke seals. The latch should have a positive latching mechanism comprising steel or brass nib (not rollerball catch) which is preferably surface mounted, secured to the door with fixings to a minimum depth of 25mm. Any lock, including deadlock, must be fitted with a turnkey mechanism, not necessitating use of a key on the room side.