As there is a wide range of standard fire door sizes available in the UK, it is surprisingly complex to understand and choose the right ones. But, how can you choose the right fire door if you’re unsure it fits the intended opening? One of the most important aspects of buying a fire door is the size.

While this may sound basic, the mix of metric and imperial size – not to mention the range of conventional dimensions – can make it difficult to decide exactly what you need. But don’t worry, we’re here to make things easier for you. In this guide, we help you choose the correct fire door size first time round, saving you both time and money. So, continue reading and get to know fire door sizes in UK better.

Why do Fire door sizes matter?

Choosing the right size of fire door is more important than you think, and the reasons are:

• If a fire door isn’t fitted properly, it won’t perform as it should, and it can be dangerous in the event of fire. A fire door is only effective when it is properly fitted.
• An ill-fitting door won’t function well in regular use. It might not close correctly, which would decrease insulation, raise the possibility of unwanted entrance, and affect fire safety.
• Consider wheelchairs, young children, people with vision impairments, and hospital trolleys when choosing a door size and opening mechanism. All of this must, of course, meet the building regulations.

Standard Fire Door Sizes in UK

The most common fire door sizes available in the UK are listed below. The main difference between fire doors and standard internal door sizes is that the former are thicker, typically 44mm, because they require additional core materials inside to meet fire safety standards. It is also important that your door frame, intumescent seals, and ironmongery (such as hinges, handles, and locks) be fire-rated and appropriate for the door’s particular fire certification. In the following table, you can see the most common standard fire door sizes in UK:

Common Fire Door Sizes

Now that you know the standard fire door sizes UK, you should be familiar with all of the fire door sizes. In the UK, fire doors come in a variety of standard sizes to fit both residential and commercial environments.  Standard internal doors are typically 35 mm thick; however, in order to comply with fire safety rules, fire-rated doors (such as FD30 or FD60) must have a thickness of 44mm for FD30 and 54mm for FD60. In the following section, you can see the conversion chart of common fire door sizes:

Common Fire Door Size Conversion Chart

If you’re unsure how to properly measure for your fire door, check out our guide on How To Measure For Internal Doors.

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FD30 Fire Door Sizes (30-Minute Rated)

As you might know, the FD30 fire doors are designed to withstand fire for at least 30 minutes. common sizes available:

Traditional UK Sizes (44mm thickness):

• 1981 x 457 mm
• 1981 x 533 mm
• 1981 x 610 mm
• 1981 x 686 mm
• 1981 x 762 mm (2’6”)
• 1981 x 838 mm (2’9”)

Metric Sizes (typically 2040mm height):

• 2040 x 526 mm
• 2040 x 626 mm
• 2040 x 726 mm
• 2040 x 826 mm
• 2040 x 926 mm

FD60 Fire Door Sizes (60-Minute Rated)

As FD60 fire doors are designed to resist fire for a longer amount of time, they’re usually thicker and heavier than other doors. The common FD60 fire door sizes include:

Difference between standard and custom fire door sizes

Standard and custom fire doors differ mostly in terms of availability and choice. Standard sizes (e.g., 1981 x 762 x 44mm) are readily available, less expensive, and suitable for the majority of standard entrances. On the other hand, custom (or bespoke) fire doors are manufactured to your precise specifications. With this kind of door, you’ll have more freedom to choose. Not to mention that custom fire doors are typically more expensive and long-lasting, but they are ideal for special buildings or certain access requirements.

By taking a look at the following table, you can easily understand their key differences:

Fire Door Sizes Regulations

There is no fixed dimension for fire door size regulations in the UK. The regulations are mostly about meeting fire safety standards like FD30 or FD60. However, there are some key points about UK fire door regulations you should know:

Height:

Usually 1981mm (6’6″)

Common Widths:

• Small openings/cupboards: 457mm / 533mm
• Tighter spaces: 610mm / 686mm
• Most common internal size: 762mm (2’6″)
• Wheelchair access: 838mm (2’9″)

Metric Fire Door Sizes (More common in Scotland & Europe):

• Height: Usually 2040mm
• Common Widths: 526mm / 626mm / 726mm / 826mm / 926mm

Fire Door Thickness:

• FD30: 44mm thick
• FD60: 54mm thick

⚠️ To confirm about the regulations that you need to meet, contact your local council for more information as this can be different from case to case.

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How to Choose the Right Fire Door Size for Your Building

One of the key points you should consider when choosing a fire door size is the building type. Do you want the door for schools, hospitals, or offices? Just look at the following table, it helps clarify on how to choose the best fire door sizes for your building:

5 Biggest Mistakes When Choosing Fire Door Sizes

If you know the biggest mistakes people make when choosing fire door sizes UK, then you can avoid them. That’s why we gathered these mistakes for you to be careful about:

1. Choosing the wrong door width: Choosing a door that is too narrow comes with problems like hindering wheelchair access or safe evacuation in the event of fire. For public buildings, 838mm or wider is often a good choice.
2. Overlooking the correct door thickness: Installing a door with the wrong thickness can decrease the door’s fire resistance. They must meet the right rating; FD30 doors are typically 44 thick, while FD60 doors are 54mm.
3. Ignoring frame compatibility: For a fire door to function as intended, it must fit correctly into a fire frame and be compatible with the appropriate hardware and seals.
4. Considering that one size fits all: The needs of different rooms and buildings vary.  Not every space can benefit from a typical door size, particularly in intricate contexts like schools or hospitals.

Find the best door for your space at Zdoors

Here at ZDoors, we make choosing the right fire door easy for you, so you don’t have to go through complicated steps. No matter what your space theme is, we offer a wide range of high-quality fire doors in standard and custom sizes to suit your space. Not only for homes and offices, but we also have options for hospitals and schools. If you’re unsure how to start upgrading for safety, accessibility, or style, our expert team is here to help. Just check out our fire door page and get in touch with our dedicated team if you have any questions or need any help regarding it.

Conclusion

We hope that this blog post has assisted you in determining the ideal fire door size UK for your requirements. We also have an amazing collection of external doors that are manufactured from high-quality, long-lasting materials like hardwood, if you’re looking to improve your doors.

Remember that a fire door’s size has a greater impact on its ability to stop smoke and fire from spreading than you may imagine. In order to meet a variety of requirements, like allowing enough room for wheelchair access, emergency evacuation, or the movement of medical trolleys, fire door sizes must also adhere to building codes.

FAQ

1) What are the most common fire door sizes?

The most common fire door sizes are 1981 x 762mm (2’6”) for internal doors and 1981 x 838mm (2’9”) for wheelchair access.

2) What is the minimum size for a fire exit door?

The minimum size for a fire exit door is typically 1981 x 762mm (2’6”). This allows for safe and efficient evacuation.

3) How does fire rating affect door size and thickness?

The higher the fire ratings, the thicker the doors are. FD30 doors are typically 44mm thick. On the other hand, FD60 doors are around 54mm thick as they need to withstand longer exposure to fire.

4)  What are the legal requirements for fire door sizes?

Building codes, such as Part B (Fire Safety) and Part M (Accessibility), require fire doors to be wide enough for escape and to meet fire resistance requirements.