What Makes a Fire Door?

Fire doors are a critical ingredient of an effective and legally compliant passive fire protection (PFP) strategy in commercial buildings. They help stop or at least delay the spread of fire through occupancy areas and escape routes.

Fire doors are either Wood, Steel or Glass and the ratings determine how long the door can withstand fire –FD30 (30 minutes), FD60 (60 minutes), FD90 (90 minutes), and FD120 (120 minutes).

A door leaf is one of the main components in a fire door set, but the structures, fittings, and furniture associated with the door also determine the door’s effectiveness in a fire situation.

If any one of these fails, the integrity of the entire fire door could be compromised.

Here’s what you need to look out for:

All components must work together

Seals, ironmongery, signage, glazing, and framing all have their part to play in ensuring effective fire door performance and, indeed, compliance.

1. 1. Around the door – Intumescent seal strips must be fixed around the door frame. These expand when exposed to heat, filling any gaps and effectively forming a seal to help contain fire and smoke for a period of time in accordance with the door’s fire rating.
   2. Above the door – Fire doors should remain closed when not in use, so door closers that automatically close the door after opening are a must. The higher the door’s fire rating, the heavier the door can be, so it’s important to fit a closer with the correct closing force.
   3. Under the door – A threshold seal or plate fills the gap underneath a door and delivers added protection from cold smoke, but the choice of seal type – drop-down, brush strip, rubber – is important to ensure smooth opening and closing on different types of floor surface.
   4. On the door – Fire-rated locks, latches and other ironmongery are essential, as they ensure that the door stays shut and remains an effective barrier, even when the fittings are subjected to fierce heat.
   5. Surrounding the door – A fire-rated frame must be compatible with the fire rating of the door leaf. If the frame is not appropriately fire-rated, the door leaf cannot be classed as a fire door!
   6. Attaching the door – Fire doors should usually be hung on three hinges, and the use of intumescent fire hinge plates will afford additional protection.
   7. In the door – Features like glazed panels and air grilles must use the correct components, including fire-rated glass, a glazing bead system to keep the glass in place under severe heat, an intumescent system to seal the grilles and inhibit the spread of fire and smoke, and other fire-rated fittings. For fire doors that also need a letterbox, one should be fitted that includes an intumescent liner that will expand in response to heat, and close off the letterplate opening.
   8. For users of the door – Finally, signage on fire doors is mandatory for fire safety compliance, as it prescribes actions on the part of users that are fundamental to ensuring the fire door can do its job.

Fire doors: more than just the sum of their parts

It’s clear, then, that an effective and compliant fire door – even if it already bears on its edge (as it should) a label stating it’s fire rating and manufacturer – is ultimately dependent on many factors other than the fire resistance of the door leaf itself.

In practice, keeping on top of this can be tricky for the individuals responsible for fire safety in commercial buildings.

Fire doors may be fitted, but hung incorrectly or in the wrong frame – an error that is not readily visible.

Fittings, furniture, and seals that have broken or worn out over time may have been replaced – with the best intentions – with components that are not compliant, because the fitter did not have adequate knowledge of fire safety regulations.

In short, although a fire door may be clearly in evidence, it may not actually be capable of doing what it was designed to.

But who’s going to point this out to you before a fire takes hold?

Get help with fire doors and more

At CFP, we work with companies, landlords, facilities managers, and managing agents to ensure commercial buildings’ passive fire protection (PFP) is both effective and legally compliant.

For more information about how we can help you at every stage of your PFP journey – from risk assessments and fire protection surveys, to fire doors, compartmentation, fire exit strategy, fire protection design and maintenance, and more, get in touch.