Nfpa 80 fire doors and other opening protectives.
Gap between double fire doors.
In this case an allowance should be made for the degree of bevel.
I understand that the gap around a door should be no more than 3mm 1mm to allow the intumescent seal to expand although there is more leeway with the bottom of it.
1 8 meeting edges for a pair of doors.
Under door threshold gaps should be in accordance with the manufacturer s installation instructions for the particular doorset design.
Bs 8214 2008 states that the gap along the sides top and between the leaves of a double door should be 3 mm 1 mm.
Under the bottom of a door.
Contains information on maximum gap allowances for different types of fire doors.
For example the maximum door gap dimension for 3 4 hour and greater rated wood fire doors is 1 8 in no over tolerance dimension is permitted.
The meeting edge clearance between double egress pairs of doors measured from one side only may potentially exceed 3 16 since the measurement would be from the pull side of one door to the push side of the other door.
If the doors are solid wood they are susceptible to swelling and shrinkage in response to changes in the weather and these shifts are magnified in the case of double doors.
Double doors can make a grand impression at the main entrance to a home but if there is a gap between them they re losing a lot of heat.
It s recommended to aim for a 3mm gap to ensure adequate room for the intumescent strips to activate in the event of a fire and for the smoke seal strips if installed to not get damaged by the opening and closing of the door.
3 4 between door and frame.
Worryingly the fire door inspection scheme fdis recently highlighted that three quarters of all fire doors inspected in 2019 were condemned as not fit for purpose.
The lsc does not specify a minimum gap for corridor doors of 1 8 inch and in addition the lsc specifically states that compliance with nfpa 80 standard for fire doors and fire windows is not required 18 19 3 6 3 1.
Therefore it is incorrect to apply the 1 8 inch gap.
Control of door gaps gaps between fire doors and the door frame should never be more than 4mm or less than 2mm.
In general clearance for those allowed gaps are as follows.
1 8 for more detailed gap information refer to nfpa 80 section 6 3 1 7 and section.