Fire Doors – Everything You Need to Know

As a vital part of your building’s ‘passive fire resistance’ – a blanket term for fire safety equipment that is designed to stop fires from spreading – fire doors not only provide a means of evacuation, they also prevent smoke and flames from reaching other areas within a premises. Ensuring that your property is sufficiently equipped with fire resistant doors is vital, as is keeping them maintained so they’re always operating at the optimum level.

In this comprehensive review of fire doors, we going to cover everything from what they are and how they work to the ratings that indicate their resistance levels and the regulations that cover their use – and a whole lot more.

Quick Links

• What is the purpose of fire doors?
• Which doors need to be fire doors?
• What makes a door a fire door?
• How do fire doors work?
• Fire door ratings
• Fire door regulations
• British Standards Institution
• Where should fire doors be fitted?
• Who is responsible for installing and maintaining fire doors?
• Fire door testing procedures

What is the purpose of fire doors?

Fire doors create a passive fire safety system, protecting commercial buildings from the spread of fire by confining it to a specific area for a longer period of time than would be the case if they were not there. This allows people within the building enough time to escape via alternative routes that might otherwise be cut off by fire, while also giving the fire service more time to attend the scene and hopefully limit the amount of damage caused.

Fire doors are a legal requirement for particular buildings, including most commercial and multi-occupied residential buildings, with new regulations having been introduced in 2023 for multi-storey residential buildings as a direct result of the official inquiry into the Grenfell Tower disaster.

Which doors need to be fire doors?

In a commercial building, fire doors are employed to provide a safe escape route through a building. This could either be a vertical escape route that directs people towards a stairwell, or a horizontal escape route with compartmentalised spaces, such as rooms and corridors that are on the same floor.

What makes a door a fire door?

A fire door needs to meet specific standards and have been thoroughly tested before it can be legally used as a fire door. Each door needs to be rated as to how long it can withstand the effects of a fire and prevent flames and smoke from passing into the next compartment of the building in question. Different doors have different ratings, but the minimum rating is FD30, which means that the door can resist a fire for at least 30 minutes.

To qualify as a fire door, both the door itself and any fixtures attached to it (such as hinges and handles) need to have at least the same fire rating. Fire doors can also include glazing, and this should also be fire resistant to at least the same degree as the fire resistance rating of the door itself.

How do fire doors work?

Fire doors can be made from a number of different materials, including aluminium and steel, although timber (often oak) is probably the most common. The door itself, the frame and any hardware attached to the door all play their part in providing a barrier to fire and smoke, preventing it from spreading.

Fire doors should also have intumescent seals fitted. Most doors will have space between them, their frame and the floor beneath, which means that they can be easily opened and closed. On a standard door, this is usually about 8mm, but on a fire door, this space should not be greater than 4mm. However, such a gap is still enough to allow smoke to pass through in the event of a fire. An intumescent seal is therefore fitted to the edges of a fire door and expands under heat to fill those gaps, thus preventing any flames and smoke from getting through.

By design, fire doors must also be kept closed at all times when not in use, with automatic closing devices being incorporated to ensure that they can’t be accidentally left open – propping them open is generally in violation of fire safety regulations.

Fire door ratings

The amount of time a fire door can withstand a fire is key to how well it will do its job. The longer a door resists, the greater chance there is of everyone in the building being able to escape.

Designed from a number of different materials and varying in density, there are some specific ratings for the integrity of a fire door. The BWF (British Woodworking Federation) provides the certification for these ratings.

• FD30 – 30 minutes of resistance
• FD60 – 60 minutes of resistance
• FD90 – 90 minutes of resistance
• FD120 – 120 minutes of resistance
• FD240 – 240 minutes of resistance

Fire doors are tested from both sides to gauge the integrity and stability of the door during a blaze. Doors with an FD60 rating or higher are generally not used for escape routes, they are usually recommended for containing a fire or preventing it from reaching high-risk areas that a company may wish to protect.

Fire door regulations

The regulations for installing a fire door depend on whether it is an internal or external door and whether the installation is in a new or existing commercial building. 

For new properties, a combination of relevant building regulations and the Regulatory Reform (Fire Safety) Order 2005 apply, while for existing buildings it is just the latter, brought in to replace the numerous and disparate fire safety laws in existence prior to this point.

• Regulatory Reform (Fire Safety) Order, 2005

A comprehensive piece of legislation, the Regulatory Reform (Fire Safety) Order combines every element of fire safety in commercial environments into one place. The reform covers all facets, including the fire safety duties of employers and responsible persons, how the regulations are enforced, the appeal process and more.

In relation to fire doors, the Regulatory Reform emphasises the importance of keeping all fire safety equipment well maintained and inspected regularly by a professional. It also states that only components that meet certified standards may be used in fire doors.

• Building Regulations

For those doors being fitted in brand-new properties, building regulations must be met. Those that apply to doors include Approved Document E (resistance to sound), Approved Document F (ventilation), Approved Document L (conservation of fuel and power), Approved Document M (access to and use of buildings) and Approved Document N (glazing safety).

However, when it comes to fire safety, the main regulations are detailed in Approved Document B (fire safety), 2006. The guidelines govern a number of criteria that must be met. These include where fire doors should be fitted, the length of the fire resistance period that each door should provide, where fire door signage should be placed, where smoke seals are needed and more.

British Standards Institution

Help exists for organisations that are attempting to comply with the various regulations that govern their fire safety. The British Standards Institution (BSI) is ideal in this scenario, providing a range of accreditations and standards for companies to adhere to. 

BS EN 1634 is perhaps the most important standard that relates to fire doors. BS EN 1634-1 covers resistance to fire, while BS EN 1634-3 relates to smoke permeability. BS EN 1634-2, incidentally, covers the actual tests that must be carried out.

The one most closely related to timber fire doors is the BS 8214, which gives recommendations as to their specification, installation and maintenance. Please note, however, that BS 8214 applies only to doors with a fire rating of up to FD120 when tested in accordance with BS 476-22 or BS EN 1634-1.

Where should fire doors be fitted?

When putting together a fire safety plan, many large commercial buildings are divided into compartments. Passive fire safety measures – such as fire doors – are located at the borders between these compartments, so that any fire can be isolated and smoke and flames prevented from passing from one compartment to the next.

Your fire risk assessment will identify which points within your premises need fire doors to support the compartmentation strategy.

Who is responsible for installing and maintaining fire doors?

Fire doors must be installed and maintained by what the Fire Safety Order refers to as a ‘competent’ person. This is someone who has the training, experience and knowledge to do the job in question. 

Here at Scutum South South East, all our fire safety technicians are fully competent to carry out installation and maintenance on all fire doors, whether they were supplied by us or not.

Fire door testing procedures

In order to certify that fire doors and related components meet the levels required by law, they are put through rigorous testing to BS EN 1634-1:2014 standards. A revision of similar standards from 2000 and 2008, testing is carried out on all unit parts as a complete assembly, simultaneously trialling the door, frame, seals, locks, hinges, latches and more.

This will ensure that all component parts complement each other in their passive fire resistance capabilities.

From the fire risk assessments required to identify your need for fire doors to the fire doors themselves, you can’t do better than talk to the experts at Scutum South East. We’ve been supporting local businesses across South East England, including London and Surrey, with all their fire safety measures for decades.

As well as supplying, installing and maintaining external and internal fire doors, we are also able to supply fire-rated door finishes and glazing to enable your fire doors to keep your building both safe and aesthetically pleasing.

If you want to know more or ask for a free site visit, please get in touch with us today.