Understanding Standard UK Door Sizes

Choosing the right door size is crucial for any UK home improvement project. At Online Door Store, we've helped countless customers navigate the world of door dimensions. Let's break down what you need to know about standard UK door sizes.

 

Key Takeaways:

 

• Standard internal door height: 1981mm (6'6") in England/Wales, 2040mm (6'8") in Scotland
• Common door widths range from 457mm (18") to 926mm (36.5")
• Internal doors are typically 35mm thick, while fire doors are thicker at 44mm
• Accurate measurements are essential for a perfect fit
• Older homes may have non-standard sizes

 

Overview of Door Sizes in the UK

 

Key Door Size Measurements (Metric and Imperial)

 

In the UK, door sizes can vary depending on where you are. In England and Wales, the standard internal door height is 1981mm (6'6"), while in Scotland, it's slightly taller at 2040mm (6'8").

 

When it comes to width, there's more variety. The most common widths include:

 

• 457mm (18")
• 533mm (21")
• 610mm (24")
• 686mm (27")
• 762mm (30") - This is the most common width
• 838mm (33")
• 926mm (36.5")

 

Remember, these are standard sizes. If you live in an older property, you might encounter non-standard dimensions. That's why measuring is so important. Take a look at our internal doors for inspiration and initial measurements.

 

External vs. Internal Door Sizes

 

Internal and external doors serve different purposes, and this is reflected in their sizes.

 

Internal doors are typically 35mm thick for imperial sizes or 40mm for metric. They're designed for indoor use and don't need to withstand harsh weather conditions.

 

External doors, on the other hand, need to be more robust. They're usually thicker and made from tougher materials to provide better insulation and security. Take a look at our external doors to get an idea of what to expect. The exact size can vary, which is why custom options are common for external doors.

 

Importance of Accurate Measurements

 

Getting your measurements right is crucial to avoid costly mistakes. Here's what you need to do:

 

1. Measure the height, width, and thickness of your existing door or door frame.
2. Take measurements at multiple points - door frames can warp over time.
3. For new installations, remember to account for the door frame when measuring the opening.
4. Consider the swing arc, especially in tight spaces.
5. Don't forget to allow for floor clearance.

 

If you're replacing an existing door, measure both the door and the frame. For new installations, measure the opening and factor in the frame size. When in doubt, it's always better to measure twice and order once.

 

Standard Door Types and Specifications

 

Fire Doors and Legal Compliance

 

Fire doors are a crucial safety feature in many buildings. They're designed to slow the spread of fire and smoke, giving occupants more time to evacuate. Here's what you need to know:

 

• FD30 fire doors provide 30 minutes of fire resistance and are typically 44mm thick.
• FD60 fire doors offer 60 minutes of protection and are usually 54mm thick.
• Fire doors are required by law in certain situations, such as:
  • Between a house and an integral garage
  • In houses of multiple occupation (HMOs)
  • In commercial buildings, following specific regulations

 

When installing fire doors, it's crucial to follow building regulations to ensure they function as intended. Browse our fire doors to gain a better understanding of this.

 

Door Lippings and Trimming Allowances

 

When you look at the edge of a door, you'll notice a strip running along the vertical sides. These are called door lippings, and they play a crucial role in both the door's durability and its ability to fit various frames.

 

Door lippings serve as a protective barrier for the door's core. They're typically made of solid wood, even on hollow-core doors, and they shield the more vulnerable interior from everyday bumps and knocks. This added protection extends the life of your door, keeping it looking good for years to come.

 

When you're dealing with slightly non-standard door frames, lippings allow for some adjustment. Most internal doors can be trimmed by up to 12mm on each side, giving you some wiggle room if your frame is a bit smaller than expected. This can be a real lifesaver, especially in older homes where door openings might not conform to modern standards.

 

However, it's important to note that not all doors are created equal when it comes to trimming. Fire doors, for instance, are a different beast altogether. Due to their specialised construction, fire doors typically have a much smaller trimming allowance - usually only about 3mm per side. Trimming more than this could compromise the door's fire-resistant properties, potentially putting lives at risk.

 

Before you start trimming any door, always consult the manufacturer's guidelines. These will provide specific information about how much can be safely removed without affecting the door's integrity or, in the case of fire doors, its safety rating. If you're unsure, it's always better to err on the side of caution and seek professional advice. 

 

At Online Door Store, we're always happy to provide guidance on door trimming and fitting to ensure you get the perfect fit for your home.

 

Custom and Non-Standard Door Sizes

 

When to Consider Custom-Sized Doors

 

While standard sizes fit most needs, there are situations where custom doors are necessary:

 

1. Older properties: Many period homes have non-standard openings.
2. Unique architectural designs: Modern or unconventional buildings may require bespoke sizes.
3. Specific functional needs: For example, extra-wide doors for accessibility.
4. Aesthetic preferences: You might want an oversized door for a grand entrance.

 

Custom doors typically cost more and take longer to produce, but they ensure a perfect fit for your specific requirements. We offer made-to-measure doors to suit this exact need.

 

Common Issues with Non-Standard Sizes

 

When dealing with non-standard sizes, you might encounter these challenges:

 

1. Limited choice: Fewer style options are available in non-standard sizes.
2. Higher costs: Custom-made doors are usually more expensive.
3. Longer lead times: Custom doors take longer to manufacture and deliver.
4. Installation complexities: Non-standard sizes may require specialised installation.

 

To avoid these issues, always double-check your measurements before ordering. 

 

Building Regulations and Compliance

 

Fire Door Requirements in Rental Properties and HMOs

 

Fire safety is particularly important in rental properties and Houses in Multiple Occupation (HMOs). Here are the key requirements:

 

• In HMOs, fire doors are required for all rooms that open onto an escape route.
• FD30 rated doors (30-minute fire resistance) are typically sufficient for most situations.
• All fire doors must have self-closing devices and intumescent strips.
• Landlords are responsible for ensuring all fire doors are correctly installed and maintained.

 

Failure to comply with these regulations can result in hefty fines and, more importantly, put lives at risk. Always consult with local authorities or a fire safety expert if you're unsure about the requirements for your property.

 

Part 'M' and Accessibility Standards

 

Part 'M' of the UK Building Regulations focuses on access to and use of buildings. Here's what you need to know about door sizes for accessibility:

 

1. Minimum door widths:
   • For most internal doors: 800mm clear opening width
   • For wheelchair users: 825mm clear opening width
   • For accessible toilets: 925mm clear opening width
2. Other considerations:
   • Door handles should be between 900mm and 1100mm from the floor
   • Doors should be easy to open, with a maximum force of 30N required

 

Remember, these requirements apply to new buildings and significant renovations. Always check the latest regulations or consult an expert when planning your project.

 

Measuring and Installing UK Doors

 

How to Measure for Door Replacement

 

Accurate measurements are crucial for a successful door replacement. Follow these steps:

 

1. Measure the height of the door in three places: left, centre, and right.
2. Measure the width in three places: top, middle, and bottom.
3. Measure the thickness of the door.
4. Check the dimensions of the door frame.
5. Note the direction of the door swing (left or right-handed).

 

Always use the smallest measurement when ordering to ensure the door will fit. It's easier to plane down a door that's slightly too big than to fill gaps around one that's too small.

 

How Online Door Store Can Help

 

At Online Door Store, we're committed to making your door buying experience as smooth as possible. We offer:

 

1. A wide range of standard and custom sizes
2. Expert advice on choosing the right door
3. Detailed measuring guides and installation tips
4. High-quality doors from trusted manufacturers
5. Excellent customer service to support you every step of the way

 

Remember, the key to getting the right door is accurate measurements and understanding your specific needs. Don't hesitate to reach out if you need any assistance.

 

You can contact us online via a form, or via the following:

 

Our telephone lines are open Monday-Friday from 8:30am-5:30pm, call us for FREE ADVICE on 0208 158 6700 

 

Email us at: enquiries@onlinedoorstore.co.uk

 

FAQs on Standard UK Door Sizes

 

1. Q: What's the most common internal door size in the UK?

 

 A: The most common size is 1981mm x 762mm (78" x 30") or (6'6" x 2'6").

 

2. Q: How do I know if my door is fire-rated? 

 

A: Fire-rated doors are typically thicker (44mm for FD30) and should have a certification label on the top edge.

 

3. Q: What door size do I need for wheelchair access? 

 

A: For wheelchair access, you need a door with a clear opening width of at least 825mm.