What Are the Standard Door Sizes in the UK? Your Complete Guide
Standard door sizes in the UK follow two reference sets: 1981 x 762 x 35mm in England and Wales, and 2040 x 726 x 40mm in Scotland, written as height x width x thickness. Internal doors run from 457 to 838mm wide in imperial ranges and from 526 to 926mm in metric ranges, and thickness decides which hinges and latches fit. External doors are thicker, with 762 to 915mm widths at 1981mm high, and French, patio, bi-fold and garage doors are sized by panel count and opening width. Fire doors match internal widths but are 44mm (FD30) or 54mm (FD60) thick, and trimming is limited by the certified specification.
Imperial sizes convert to millimetres by multiplying inches by 25.4, and country and property age decide which family a home uses. Wheelchair access depends on clear opening, not leaf width, under Approved Document M. Non-standard openings are fitted by planing, altering the lining or ordering made-to-measure, and measuring the opening or the existing leaf leads to the right size.
Table of Contents
What Is the Standard Door Size in the UK?
The standard door size in the UK is 1981 x 762 x 35mm in England and Wales and 2040 x 726 x 40mm in Scotland, written as height x width x thickness. The standard width is 762mm (2ft 6in) in England and Wales and 726mm in Scotland. The standard height is 1981mm (6ft 6in) in England and Wales and 2040mm in Scotland. A listing of 762 x 1981 x 35mm describes the same door as 1981 x 762 x 35mm, so comparing the order against the largest number confirms which figure is the height.
A taller imperial option of 2032mm (6ft 8in) also appears in manufacturer ranges. Imperial widths rise in 3-inch steps of about 76mm: 457, 533, 610, 686, 762 and 838mm, and the 711mm (28in) leaf is the one width outside that pattern. Metric widths rise in 100mm steps: 526, 626, 726, 826 and 926mm.
What Are the Standard Internal Door Sizes?
Standard internal door sizes in the UK are 1981mm high and 457 to 838mm wide in imperial ranges, or 2040mm high and 526 to 926mm wide in metric ranges.
Imperial internal door sizes
| Leaf width (mm) | Typical use |
|---|---|
| 457 | Cupboards and wardrobes |
| 533 | Cupboards and wardrobes |
| 610 | Small rooms with limited wall space |
| 686 | Bathrooms and smaller rooms |
| 711 | Less common width listed by some manufacturers |
| 762 | Most common internal door, used in bedrooms, living rooms and hallways |
| 838 | Wider access routes, including step-free routes for wheelchair users |
Metric internal door sizes
| Leaf width (mm) | Description |
|---|---|
| 526 | Narrowest standard metric width |
| 626 | Narrow openings |
| 726 | Most common metric width, standard in Scotland |
| 826 | Wider openings |
| 926 | Widest standard metric leaf, used for accessible routes |
What Are the Standard External Door Sizes?
Standard external door sizes in the UK are 1981mm high and 762 to 915mm wide, with 44mm the most common thickness.
Front and back door sizes
External leaves are thicker than internal leaves for security and insulation. The minimum thickness is 40mm. Timber leaves range from 44 to 56mm and composite leaves from 44 to 70mm.
The table below lists common external leaf sizes in height x width order, with the imperial name for each.| Leaf size (mm) | Imperial name | Note |
|---|---|---|
| 1981 x 762 | 6ft 6in x 2ft 6in | Most common front door |
| 1981 x 838 | 6ft 6in x 2ft 9in | Wider front door |
| 1981 x 915 | 6ft 6in x 3ft 0in | Widest standard height-1981 leaf |
| 2032 x 813 | 6ft 8in x 2ft 8in | Taller option |
| 2083 x 864 | 6ft 10in x 2ft 10in | Taller and wider option |
| 2134 x 915 | 7ft 0in x 3ft 0in | Tallest standard leaf listed |
French, patio, bi-Fold and garage door sizes
| Door type | Typical width (mm) | Note |
|---|---|---|
| French doors | 1200, 1500 and 1800 | External leaves are normally 44mm thick |
| Sliding patio doors, two panels | About 1800 | Width rises with each added panel |
| Bi-fold doors | About 1800 (two panels) to 6400 (seven panels) | Ranges vary by manufacturer; thickness is 44 to 70mm |
| Garage doors | 2134 | Listed as 1981 x 2134mm and 2134 x 2134mm (height x width) |
Stacking space for folded panels reduces the clear opening of a bi-fold door.
What Are the Standard Fire Door Sizes?
Standard fire doors match internal door widths and heights but are thicker: FD30 doors are usually 44mm thick and FD60 doors usually 54mm thick.
FD30 resists fire for 30 minutes and FD60 for 60 minutes. Some products are listed at 45mm for FD30. Thickness differs by manufacturer and certified core construction, so the product certificate states the exact figure.
Common imperial fire door widths are 27in (686mm), 30in (762mm) and 33in (838mm). Metric fire doors follow the 2040mm height with widths such as 626, 726 and 926mm.
A fire door performs as tested only as a complete assembly. The leaf, frame, hinges, intumescent seals and the gap around the leaf all form part of the certified specification. Trimming beyond the manufacturer’s stated limit voids the certification. Approved Document B governs where fire doors are required in dwellings.
How Are Door Sizes Converted Between Imperial and Metric?
Imperial sizes convert to millimetres by multiplying inches by 25.4. Imperial doors are 78in high, and 78 × 25.4 gives 1981.2mm, listed as 1981mm.
The table below shows how each common imperial width converts and how suppliers round the result.
| Imperial width | Inches | Calculation | Exact result (mm) | Listed width (mm) |
|---|---|---|---|---|
| 1ft 6in | 18 | 18 × 25.4 | 457.2 | 457 |
| 1ft 9in | 21 | 21 × 25.4 | 533.4 | 533 |
| 2ft 0in | 24 | 24 × 25.4 | 609.6 | 610 |
| 2ft 3in | 27 | 27 × 25.4 | 685.8 | 686 |
| 2ft 6in | 30 | 30 × 25.4 | 762.0 | 762 |
| 2ft 9in | 33 | 33 × 25.4 | 838.2 | 838 |
Metric sizes convert the other way: divide millimetres by 25.4. A 2040mm height equals 80.3in, a 726mm width equals 28.6in and an 826mm width equals 32.5in.
The two families are not interchangeable. A 2040mm door is 59mm taller than a 1981mm door, so it does not fit an opening built for the shorter size without altering the lining.
How Do UK Door Sizes Vary by Country and Property Age?
Door sizes by country
| Nation | Common internal door | Accessibility guidance |
|---|---|---|
| England | 1981 x 762 x 35mm | Approved Document M, Volume 1 |
| Wales | 1981 x 762 x 35mm | Welsh Government version of Approved Document M |
| Scotland | 2040 x 726 x 40mm | Domestic Technical Handbook |
Door sizes by property age
Homes built before the 1990s mostly use imperial sizes, and 1981 x 762mm and 1981 x 686mm leaves cover the majority of their openings. New builds follow metric sizes more often, with 2040mm doors appearing across the UK.
Victorian and Edwardian homes frequently contain non-standard openings. Measuring the existing frame is more reliable than assuming a standard size in these properties.
What Is the Minimum Door Width for Wheelchair Access in the UK?
In England, a wheelchair user dwelling (M4(3)) requires a minimum clear opening width of 850mm for every door, including the entrance door. The baseline standard for all new homes (M4(1)) requires 775mm for the principal entrance door and 750 to 800mm for internal doors, depending on corridor width and direction of approach.
Clear opening width is the distance between the inside face of the door frame (or door stop) and the face of the door when it is open at 90 degrees. Approved Document M measures this gap, not the width of the door leaf. Handles and other door furniture are ignored when measuring it.
According to Approved Document M, Volume 1 (2015 edition incorporating 2016 amendments), M4(1) applies to every door to a habitable room and to the WC on the entrance storey. The minimum corridor width depends on the clear opening of the doorway:
- 750mm clear opening: The corridor is at least 900mm wide for a head-on approach, or at least 1200mm wide where the approach is not head-on.
- 775mm clear opening: The corridor is at least 1050mm wide where the approach is not head-on.
- 800mm clear opening: The corridor is at least 900mm wide where the approach is not head-on.
A standard 826mm door leaf up to 44mm thick is deemed to satisfy the 775mm requirement.
M4(2) accessible and adaptable dwellings need an 850mm clear opening at the entrance door. Internal doors throughout the dwelling follow the same corridor table as M4(1). M4(3) wheelchair user dwellings need 850mm for the entrance door and for every internal door, from any direction of approach. M4(2) and M4(3) are optional requirements that apply only where planning permission specifies them.
These figures apply to new dwellings in England. Wales, Scotland and Northern Ireland have separate building standards and guidance.
How to Measure for the Right Size Door
To measure a door accurately, decide whether you are replacing the leaf or the whole frame, then measure width, height and thickness, check squareness and calculate double door leaf width.
5 steps give the raw measurements:
- Measure Width: Take jamb-to-jamb readings at top, middle and bottom. Use the smallest if the door cannot be trimmed.
- Measure Height: Take readings on the left, centre and right, allowing for unlaid flooring.
- Measure Thickness: Check the leaf edge; internal doors are usually 35mm.
- Check Squareness: Compare both diagonals; a difference means the frame is out of square.
- Calculate Double Door Leaf Width: Subtract the frame allowance and fitting clearance, then halve the result. A 1600mm opening with 60mm allowance and 6mm clearance gives 767mm per leaf.
How Do You Fit a Door in a Non-Standard Opening?
To fit a door in a non-standard opening, plane a standard door within its trimming allowance, alter the lining, or order a made-to-measure door.
Trimming allowance is the timber a manufacturer permits removing from a leaf edge before the structure of the leaf is affected. Solid and engineered core doors usually allow more trimming than hollow core doors. Glazed doors allow the least. The product specification states the figure, and fire doors stay within the certified limit.
The table below compares the three routes by what each changes and where each stops.
| Route | What changes | Limit |
|---|---|---|
| Plane a standard door | Leaf width or height | Manufacturer’s trimming allowance; certified limit for fire doors |
| Alter the lining | Opening width or height | Existing wall and finishes around the opening |
| Order a made-to-measure door | Leaf dimensions | Produced to order, outside stock ranges |
How Do You Choose the Right Standard Door Size?
Standard door sizes in the UK reduce to four decision paths:
- Match the existing leaf to the nearest listed size for a like-for-like replacement.
- Measure the structural opening and work backwards to the leaf for a new lining.
- Compare the clear opening, not the leaf width, with the Approved Document M figures for an accessible dwelling.
- Choose a listed size for a fire door, because trimming is limited by the manufacturer’s tested allowance.
Standard door sizes in the UK come in an imperial family and a metric family, and the conversion arithmetic earlier in this guide checks either one.
Last Thoughts
Standard door sizes in the UK follow two reference sets: 1981 x 762 x 35mm in England and Wales, and 2040 x 726 x 40mm in Scotland. Imperial sizes convert to millimetres by multiplying inches by 25.4, and thickness decides which hinges and latches fit. Approved Document M measures clear opening, not leaf width, so accessible homes need the manufacturer’s stated clear opening. Planing, lining alterations or made-to-measure doors fit non-standard openings, and measuring the existing leaf or the structural opening gives the starting figure for every standard door size in the UK. For help with choosing, measuring and fitting, see the door guide.