Understanding Fire Door Gap Regulations

Aug 26, 2022

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The key to a fire door gap.. Fire doors are designed to restrict the spread of fire and smoke through a building. This is achieved by separating spaces that could otherwise act as a conduit for fire and smoke. Additionally, in order for this to work, there must be an air gap between either side of a fire door.

Fire doors are designed to separate buildings into different compartments so that if a fire breaks out, it is contained to the area where it started.

What Is A Fire Door?

Fire doors are a critical part of fire protection in buildings. A fire door is a type of door designed to slow the spread of fire, heat and smoke from one compartment of a building to another by isolating the compartments. Fire doors can be found in almost every commercial building and business premises.

They help keep the smoke and heat in one area while allowing fresh air to enter another part of the building. This keeps everyone safe by limiting the amount of damage caused by fire and allows first responders to get inside quickly so they can stop it before it spreads to other parts of the structure or gets out of control.

Keep Fire Door Closed Sign

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What Should A Fire Door Gap Be?

A fire door should have a gap around its base so that it can swing freely. But if the gap is too large, smoke and fire may be able to escape from an adjoining room into other parts of a building.

The fire door gap required varies according to the function of the door, however, best practice is to ensure that the gap:

  • At the top and sides of the door is less than 4mm.
  • At the bottom of the door is between 8-10mm.
  • £1 coins are 3mm thick to give an idea of scale.

Fire doors prevent smoke from spreading throughout your building, preventing injuries from smoke inhalation and burns. Occupants inside of your building can remain safe for a minimum of 30 minutes through the use of regulation fire doors based on the fire door gap.

Fire doors can also save money because the smoke from a fire will damage walls, floors, furnishings and paintwork. If a fire door is present then the room should be salvageable with minimum costs as you aren’t required to replace all of your flooring or re-paint all of your walls.

Check out the video below as an example.

How Do I Shorten The Fire Door Gap?

A fire door gap can be shortened through the use of surface-mounted smoke seals and rebated drop-down smoke seals. We can close the gap on existing fire doors easily using these products. This is suitable for an existing fire door gap up to 14mm on the underside of the door.

The use of a threshold seal is a cost-effective way to prevent smoke from entering your premises. This is suitable for fire doors with gaps up to 14mm on the underside of the door. The installation process is simple, and there are many different types available depending on your requirements.

Rebated Intumescent Fire Door Seals

Rebated fire door gap seals are fitted into existing rebates in either the door leaf or frame and expand upon contact with fire to fill gaps.

The brown or white rebated intumescent fire door gap seal contains expandable intumescent material which, when subjected to heat, forms a tight seal around the fire exit.

Fire door seals help prevent fires from spreading through a building by making the doors airtight and can resist the passage of fire for up to 60 minutes. These seals are often self-adhesive for quick and easy fitting. In addition, they are available in varying sizes and colours to match the aesthetic of your premises. Lastly, our intumescent fire door seals have been tested to BS476:22 and BS476:31.

Intumescent Seal

Surface Mounted Intumescent Fire Door Gap Seals

Surface-mounted fire door gap seals should be used on doors that do not already have rebates. These surface-mounted seals are really simple to install and have self-adhesive backing that can be stuck directly to the frame or onto the surface of a door itself.

Since they can be retrofitted to existing doors, they are suitable for use with older fire door assemblies that were built without seals.

As smoke tends to travel faster than the fire itself, fire and smoke door seals act as a barrier between smoke and the interior of a building. By preventing passive inhalation at entry points, they can help protect residents from serious injury or death caused by exposure to toxic fumes during an emergency.

Single Door Seal Set

Intumescent seals, which are attached to or formed as part of a door and its frame, prevent fire and smoke from passing through a doorway.

Fire and smoke seals are available in multiple colours, built to withstand extreme heat. The surface-mounted seal comes with intumescent paper for use around lock and hinge areas.

Starting on the brush side of the self-adhesive fixing strip, peel off the backing paper and press the intumescent seal into position. A sharp knife can be used to cut around lock areas if needed.

These seals fit over hinges without leaving any gaps, providing up to 66 minutes of fire protection. The brush smoke seal must not be painted once it has been fitted to the face of a door. The face of the seal can be painted.

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Shortening your fire door gap is an easy process that can be done in just a few minutes. It’s a good idea to do so because this small step can help prevent fires from spreading from one room to another. It’s also a good idea to check the seals on your fire doors regularly and make sure they’re in good condition. If you notice that one is damaged or worn out, it should be replaced immediately by a professional.

If you have any questions about how to shorten your fire door gap, please feel free to contact us! We’re happy to help!

Additional Products: Overdoor Fire Door Closers

All fire doors, except for those leading to locked cupboards or service ducts, should be equipped with automatic door closers. These must close the door from any angle and have enough strength to overcome resistance due to latches or sealing systems, otherwise, they won’t work effectively.

The Agrippa acoustic wireless door holder can be programmed to register the sound of an alarm and only operate when the volume of that alarm is above a certain threshold. This means that it will not activate if a loud bang is heard, or any other startling noises.

Silver Agrippa Overdoor Acoustic Door Closer

This is the ideal solution for holding a fire door open and is essential for areas where access is a necessity. We can program these devices to have timed releases which will ensure the fire door is then lightweight, easy to handle and swings freely.

In addition, the closing speed can be adjusted and holding angles can be set to between 65° and 105°.

OHEAP offers a range of wireless, magnetic door retainers in three colours, black, white and brass. These are suitable if you can not cable to a fire door holder.

Acoustic overdoor door closers hold fire doors open. The closers are available in a range of finishes: black, brushed chrome, stainless steel, silver or brass.

This is a great product that will provide your building with fire protection. It is easy to install and can be installed on any fire door. This will allow anyone in the building to close their fire door without any hassle or problems.

Additional Products: Intumescent Fire & Smoke Stop Pillows

We supply intumescent fire and smoke stop pillows, which are made of a hard-wearing fireproof glass cloth filled with an intumescent chemical.

Intumescent pillows are used to pack gaps and around pipes, cables and cable trays. They can be fitted to any size opening, whether permanent or temporary. In addition, they provide fire protection whilst also sealing off smoke from the other side of a wall.

The intumescent pillows are especially suitable for computers or clean areas where work is in progress. We often advise that these are used for overnight fire protection.

Intumescent Fire Pillows

Fire pillows are designed to provide a temporary or permanent barrier against fire, used in spaces which frequently change their layout and materials. They consist of a waterproof glass cloth bag filled with organic fillers infused with intumescent additives that expand once exposed to heat.

These products weigh roughly 50g and are perfect for small spaces such as cable trunking or pipes. We have tested these with metallic pipes, cables, cable bunches, cable trays and cable ladders. In addition, these fire pillows are fire-resistant to EN1366-3 EI 120 and have been tested for airborne sound and air permeability.

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