Fire Door Fitting

Fitting a Fire Door requires a certain level of knowledge in order to conform to current fire safety legislation.

Fire door specification is covered in British Standard 476. Most door manufacturers supply door fitting instructions with each fire door and also provide fitting information on their websites.

The picture opposite shows a 30 minute fire door in our mobile workshop being routered and being prepared for fitting. Note that there is a perfectly straight rebate channel for inserting a cold smoke intumescent seal.  The attention to detail is a vital element of the fire door effectiveness and performance.

Door Frame and Liner

Just as important is the door frame/liner which needs to be to the specification of the fire door manufacturer and/or the building control department. There are limits to how much a fire door can be trimmed by too. Once these options have been decided you can then focus on the important job of fitting and fire door operation.

The fire door liner should be fitted so that there are no cavities behind the liner, top and both sides. When the door is fitted to the liner, there should be an equal gap all around of about 3mm with a maximum clearance between the bottom of the door and the floor surface of 8mm. The fitting of the cold smoke intumescent seals is crucial for effective performance.

Door Sealing

The smoke brush seal must seal on the fire door liner without stopping the door closer from closing the fire door and latching.

Testing the Seal on a Fire Door

A quick test of a fire door seal is sliding a credit card between the fire door and door liner.  The test works like this:

  • If the card jams, the Cold Smoke Intumescent seal is standing too proud.  This means that the fire door will not fully close and latch without the closer being adjusted to slam hard.  That can then become is a risk of injury and therefore dangerous to staff and clients (especially children).  Over the course of time, insufficient gap will damage the fire door liner.
  • Conversely, if the credit card drops out of the fire door gap, then there is no barrier to prevent smoke passing the fire door. The aim of fire safety is to contain fire and smoke where it occurs, and for a specified time (usually 30 or 60 minutes).

With smoke usually being poisonous it is vital to hold back the smoke from a fire to its place of origin.

A fire door on it's side with the edge being routed in preparation for fire retardant seal.