If you’re buying a door for your home in the UK, the first thing to know is that there isn’t one universal standard door size. The most common internal door size in England and Wales is 1981 x 762mm (6’6″ x 2’6″), while most Scottish homes use the metric 2040 x 726mm. The right door for your property depends on the age of the building, where it is, and whether you’re replacing an internal or external door. This guide gives you the standard UK door sizes in metric, imperial and feet, the regional differences, the widths Building Regulations ask for, and the sizes fire doors come in, so you can order the correct door first time.

What Is a Standard Door Size in the UK?

There is no single standard door size in the UK. Internal doors are made in two size systems that sit side by side: an imperial-origin series and a metric series.

The imperial series is what you’ll find in most existing homes in England and Wales. Its most common size is 1981 x 762mm (6’6″ x 2’6″), and its doors are 35mm thick. The metric series is what Scottish homes and many new builds use. Its most common size is 2040 x 726mm (6’8″ x 2’4½”), and its doors are 40mm thick.

Which one you need depends on the age of the building, whether the door is internal or external, and what the frame was built for. If you’re unsure, measure the frame before you read the tables below. The metric doors are 59mm taller, so an imperial frame won’t take one without cutting it down.

Door Size Chart (Imperial & Metric)

The two tables below list the door sizes UK manufacturers make as stock items. Every size in them is available in the internal doors range.

How to read a door size: the figures are the door leaf itself, not the frame, and height comes first. So “1981 x 762 x 35mm” is a door 1981mm tall, 762mm wide and 35mm thick. The opening in the frame needs to be a few millimetres bigger than the leaf, about 3mm at the top and each side and up to 9mm under the door, so the door swings without catching.

Imperial Door Sizes (Existing Properties, 35mm thick)

Metric Door Sizes (Scotland and New Build, 40mm thick)

Two other sizes turn up often enough to mention. 2032 x 813mm (6’8″ x 2’8″) appears in some manufacturers’ ranges alongside the metric sizes. 1981 x 914mm (6’6″ x 3’0″) is sold for wide internal openings and as an external size.

Standard Interior Door Sizes

For internal doors, the most common size in England and Wales is 1981 x 762 x 35mm, known as a 2’6″ door. This is the normal door size most people mean when they say “a standard door”. In Scotland, the taller metric 2040 x 726 x 40mm is the usual size.

If you want to keep it short, remember this: a UK internal door is usually 1981mm high, and the standard internal door width runs from 610mm to 838mm across the common sizes. 762mm is the width you’ll meet most often.

Most Common Internal Size

The most popular internal door size is 1981 x 762mm (2’6″), which gives a comfortable walkway without taking more wall than a small room can spare. For smaller spaces, 1981 x 686mm (2’3″) is the next most common, and you’ll find it on small bedrooms, bathrooms and box rooms. Both are 35mm thick.

If you’re replacing a door in a house built after the 1950s in England or Wales, the odds are strongly on one of those two sizes. A quick way to tell without a tape: a 762mm door is about the width of a standard bath, and a 686mm door is a hand’s width narrower. Measure anyway before you order, but that tells you which size to expect.

If your doors are hollow core or solid core makes no difference to the size, but it does change how much you can trim. Our guide to door cores explains the difference.

Standard External Door Sizes UK

Most UK external doors are the same 1981mm height as internal doors, in widths of 762mm, 838mm and 914mm. The difference is thickness: external doors are 44mm thick, against 35mm for a standard internal door.

External door sizes vary more than internal ones. Alongside the wall and frame, you have security, insulation, style and access to think about, and taller front doors are now common in new builds.

Standard Front Door Dimensions

The standard front door size in the UK is 1981 x 838 x 44mm (6’6″ x 2’9″). Wider 914mm (3’0″) leaves are the next step up, and taller options such as 2083 x 864mm (6’10” x 2’10”) and 2135 x 915mm (7’0″ x 3’0″) are sold for new builds and larger houses.

The extra width matters for access. Building Regulations ask for a clear opening of at least 775mm at the entrance door of a new home, and a wider leaf is the easiest way to reach it. The extra height is a design choice, not a regulation. You’ll find all of these in our external doors range.

If you’re comparing UK sizes with US or European ones, the standard door size in inches for a UK internal door is 78″ x 30″, and in feet it’s 6’6″ x 2’6″.

Double Door and French Door Sizes

Double doors come in two forms, and each is sized in its own way.

Internal double doors are sold as a pair of leaves by overall width, and both leaves are a standard single-door width. The common pairs are:

• 1220mm (two leaves of 610mm)
• 1372mm (two leaves of 686mm)
• 1524mm (two leaves of 762mm)

The height stays at the standard 1981mm, or 2040mm in the metric series.

External French doors are sold by the width of the whole frame, not the leaves. The common French door sizes in the UK are 1200mm, 1500mm and 1800mm wide, at the standard external door heights.

Sliding Patio and French Patio Door Sizes

Patio doors are built to let in as much light as the opening allows. French patio doors follow the same frame widths as French doors above, 1200mm to 1800mm. Sliding patio doors don’t need swing space, so manufacturers make them wider: from 1180mm for a two-panel set up to 4800mm for the widest standard sets. Bifold doors run wider still, from 1800mm for two panels to 6420mm for seven.

Fire Door Sizes and Thickness

Fire doors come in the same leaf sizes as standard internal doors. The difference is thickness, not height or width.

• FD30 doors: 30 minutes of fire resistance, 44mm thick.
• FD60 doors: 60 minutes of fire resistance, 54mm thick.

An FD30 door on its own is rated for fire, not smoke. A door that also holds back cold smoke carries an “S” suffix (FD30S) and has smoke seals fitted. Our fire door sizes guide lists every size, and FD30 vs FD60 explains when you need the thicker door.

Fire Door Size Regulations and Gap Requirements

Approved Document B sets out where a house needs a fire door. The door between a house and an integral garage must be a self-closing FD30S. A house with a floor more than 4.5m above ground level, which in practice means most three-storey houses and loft conversions, needs fire-resisting doors of at least FD20 on the protected stairway, and an FD30 door meets that. Flat entrance doors must be self-closing fire doorsets. Our guides on where you need fire doors and whether you need fire doors in your house go through each case.

A fire door only performs as tested when it’s fitted in the frame it was tested with, and with intumescent seals. The government’s fire door guidance quotes the industry standard for gaps: no more than 4mm around the sides and top, and as small as practicable under the door while it still swings clear of the floor.

Non-Standard UK Door Sizes

If you have an older Edwardian, Victorian or Georgian home, you may find that none of the standard doors on the market fit your frames. When you’re faced with a non-standard opening, you have two options:

1. Bespoke doors: a joinery workshop makes the door to your frame’s exact dimensions. This costs more and takes longer, but you get a door that fits without cutting.
2. Trimming: buy a standard door that’s a little larger and cut it down. How much you can remove depends on the door. JELD-WEN’s moulded and flush doors allow up to 4mm off each long edge and 6mm off the bottom, and the top edge shouldn’t be cut. Some doors allow up to 15mm an edge. Check the manufacturer’s allowance before you buy, and read our note on door cores, because a hollow core door has less solid timber at the edge to cut into.

Here is how much the two brands we sell most allow, taken from their own technical information. Figures are the maximum off each edge unless stated.

Three things to take from that table. Some fire doors cannot be trimmed at all: LPD’s Belize FD30 is one of them, so measure before you buy. Deanta asks for the trim to come off in equal amounts from opposite edges, not all from one side, and for a trimmed edge to be sealed straight away. LPD lists one figure per edge without saying whether it’s per edge or per pair, so treat it as the maximum for each edge and check the fitting sheet in the packaging before you cut.

The allowance is a hard limit, not a suggestion. Trim past it and the manufacturer’s guarantee no longer applies. JELD-WEN puts it plainly: “Should any critical components be affected by trimming past the recommended amount, the stability and performance of the door cannot be guaranteed and will invalidate the warranty.” On a fire door the stakes are higher. Trimming beyond the fitting instructions, or cutting the edge that carries the certification label, voids the fire certificate, and the door is no longer a fire door in the eyes of Building Control or your insurer. If the opening needs more than the allowance, order the next size down and pack the frame, or go bespoke.

Building Regulations and Wheelchair Access

Approved Document M (Access to and use of buildings) sets minimum clear opening widths for new homes, so that a wheelchair user can get through the entrance and into the rooms on the entrance storey. Clear opening width is measured from the face of the open door to the frame or stop on the other side, so it’s always less than the width of the leaf.

For a new dwelling built to the baseline M4(1) standard:

• The entrance door needs a clear opening of at least 775mm.
• Every door to a habitable room, and to the WC, on the entrance storey needs a clear opening of 750mm, 775mm or 800mm, depending on how wide the corridor is and whether you approach the door head-on.

Approved Document M also gives the door size that satisfies this: “a standard 826mm door leaf up to 44mm thick will be deemed to satisfy a requirement for a clear opening width of 775mm”. So if you need an accessible internal doorway, a 2040 x 826mm metric door is the size to specify. The 926mm width gives more room again for wheelchair access. In the imperial series, an 838mm leaf is the nearest size, and the minimum door width UK regulations ask for is a clear opening figure, so check it against your frame rather than the leaf alone.

How to Measure a Door and Frame

One rule before you start: measure the inside of the frame, where the door will sit, not the old door. Old doors warp and get planed over the years, so they’re no guide to the opening. Our step-by-step guide to measuring up for an internal door has photos for each step.

1. Door Width

Put the tape inside the frame and measure the width at three points: top, middle and bottom. Record the largest of the three and order the door size that matches it. A timber door is made with a trimming allowance, so you plane it down at the narrower points; a door ordered to the smallest figure leaves a gap you can’t fill. If the three measurements differ by more than the door’s trimming allowance, the frame is out of square and needs sorting before you order a door. Don’t plan to trim your way out of it: cutting past the allowance voids the guarantee.

2. Door Height

Measure from the floor (or the sill) to the underside of the head of the frame, once on the left and once on the right. Again, take the larger figure.

3. Door Thickness

If you have an existing door, measure its thickness. It’ll be one of four figures: 35mm for an imperial internal door, 40mm for a metric internal door, 44mm for an external or FD30 fire door, and 54mm for an FD60 fire door.

4. Frame Size

If you’re replacing the door and the frame together, measure the structural opening in the wall. There’s no single standard door frame size in the UK, but as a rule of thumb the opening needs about 51mm more width and 63.5mm more height than the door leaf, to take the lining and the fitting gap. Our guide to fitting a door frame covers the rest, and you’ll find linings and frames in our door frames range.

Worked example: from frame measurement to door size

Say the inside of your frame measures 1990mm high and 768mm wide at the widest points. Take off the fitting gaps, 3mm each side and at the top and up to 9mm at the bottom, and you’re looking for a door about 762mm wide and between 1978mm and 1984mm tall. That’s a 1981 x 762mm door, the most common size there is, with no trimming needed on the width and a millimetre or two off the bottom.

Now say the frame is 800mm wide. A 762mm door leaves a 19mm gap each side, far too much. The next size up, 838mm, needs 19mm off each side plus the 3mm gaps, about 22mm a side. LPD’s Oak 4P allows 8mm a side, Deanta’s standard doors 16mm, so neither will do it. That opening needs a new lining to bring it down to a stock size, or a bespoke door. Knowing that before you order saves a wasted door.

The rule: find the stock size closest to your opening, check the difference against the trimming allowance in the table above, and if it’s outside the allowance, sort the frame rather than the door.

Final Words

Choosing the right door in the UK takes a little care and a working knowledge of the common sizes. As a rule, go for 1981 x 762mm for a regular internal door in England and Wales, 2040 x 726mm in Scotland, 1981 x 838mm for a front door, and 2040 x 826mm where the doorway needs to meet Building Regulations for access. Measure three times before you buy and order once.

For readers working in other units, the most common standard door size is 1.981m x 0.762m (198.1 x 76.2cm) for internal doors and 1.981m x 0.838m (198.1 x 83.8cm) for front doors. Every size on this page is quoted in mm, which is how UK doors are sold.

FAQ

What size are doors in the UK?

The most common internal door in England and Wales is 1981 x 762mm, and in Scotland 2040 x 726mm. External doors are usually 1981mm high, or taller up to 2135mm in new builds, in widths of 762mm to 914mm.

Are all doors in the UK the same size?

No. Sizes vary from house to house, between regions, and between internal and external doors. Older houses and bespoke projects can fall outside the standard sizes altogether.

How wide is a standard door?

For internal doors, 762mm is the most common width. For better access, 826mm and 838mm are common, and 610mm or 686mm are used in narrow spaces.

Are UK door sizes metric or imperial?

Both. The imperial sizes are still known by their old names, such as 2’6″ or 2’9″, but every door is sold and ordered in millimetres. The metric series (2040mm high) is a separate set of sizes, not a conversion of the imperial ones.

What is the standard height of a UK internal door?

The most common internal door height is 1981mm. In Scotland, and in many new builds, it’s 2040mm.

Are all doors 35mm thick?

No. 35mm is the thickness of a standard imperial internal door. Metric internal doors are 40mm, external doors and FD30 fire doors are 44mm, and FD60 fire doors are 54mm.

What size opening does a 762mm door need?

As a rule of thumb, the structural opening needs about 51mm more width and 63.5mm more height than the door, so about 813 x 2045mm for a 1981 x 762mm door. Frame and lining sizes vary, so measure the lining you’re fitting rather than relying on the rule.

Will a 30 inch door fit a 32 inch opening?

Yes, if the 32″ (813mm) figure is the structural opening rather than the frame’s clear opening. A 30″ (762mm) door needs about 2″ (51mm) of extra width for the lining and fitting gaps, which is where the 32″ opening comes from. If 32″ is the inside of an existing frame, a 30″ door will leave a gap on each side, and you’d want the 33″ (838mm) door instead.

Is a door 2 metres tall?

Close, but no. The two standard heights are 1981mm (6’6″) in England and Wales and 2040mm (6’8″) in Scotland and the metric range. Both are within 4cm of two metres, which is why 2m is a common guess.

What is a good size for a front door?

1981 x 838mm (6’6″ x 2’9″) is the standard front door size in the UK and suits most houses. Go to 914mm (3’0″) if you want a wider entrance or need to meet the 775mm clear opening that Building Regulations ask for in a new home. Taller doors, 2083mm and 2135mm, are a style choice for new builds and larger houses.

What is the standard door size with frame?

There’s no one answer, because frames and wall construction vary. To order the right door, measure the internal opening of the frame and the clear opening, not just the door leaf. The frame’s internal opening is the figure that decides which door fits.

Sources

• Approved Document M, Volume 1: Dwellings (2015 edition incorporating 2016 amendments), paragraphs 1.9, 1.14 and 1.15 and Table 1.1, HM Government: https://assets.publishing.service.gov.uk/media/5a7f8a82ed915d74e622b17b/BR_PDF_AD_M1_2015_with_2016_amendments_V3.pdf
• Approved Document B, Volume 1: Dwellings (2019 edition incorporating 2020 and 2022 amendments), paragraphs 2.21, 5.7 and C5 and Table C1, HM Government: https://assets.publishing.service.gov.uk/media/67d02386f5aaff610c9f5f06/Approved_Document_B__fire_safety__volume_1_-_Dwellings__2019_edition_incorporating_2020_and_2022_amendments.pdf
• Fire Safety (England) Regulations 2022: fire door guidance, GOV.UK: https://www.gov.uk/government/publications/fire-safety-england-regulations-2022-fire-door-guidance/fire-safety-england-regulations-2022-fire-door-guidance
• JELD-WEN, How to measure an interior door: https://www.jeld-wen.co.uk/how-to-measure-an-interior-door
• JELD-WEN, Moulded and flush door fitting instructions: https://www.jeld-wen.co.uk/getmedia/566ee1e7-72f1-4e3c-9419-1ede12bea07c/Moulded-and-Flush-Door-Fitting-Instructions.pdf.aspx?ext=.pdf
• JELD-WEN, Will trimming my door have an effect on my warranty or guarantee?: https://www.jeld-wen.co.uk/advice/faq-s/interior-doors/will-trimming-my-door-over-the-recommended-sizes-effect-my-guarantee
• LPD Doors, Oak 4P technical information (lipping and trimming, internal and FD30): https://lpddoors.co.uk/products/oak-4p/
• LPD Doors, Oak Belize pre-finished technical information (internal, FD30 and FD60): https://lpddoors.co.uk/products/oak-belize-pre-finished/
• Deanta, FAQs (32mm total on standard and metric doors; 30mm FD30; 6mm Architectural and Urban): https://deantawood.co.uk/faqs/
• Deanta, Q-Mark FD30 Type 5 installation instructions (15mm per edge Feature range, 3mm Architectural, 2 to 4mm gaps): https://deantawood.co.uk/wp-content/uploads/2024/04/Q-Mark-FD30-Type-5-Rev-3.pdf
• Deanta, Caring for your door (trim in equal amounts, reseal trimmed edges): https://deantawood.co.uk/caring-for-your-door/
• BWF Fire Door Alliance, How to ensure fire door certification is retained: https://firedoors.bwf.org.uk/wp-content/uploads/guide-to-maintaining-certification-on-fire-doors.pdf
• Door Station, Standard UK door sizes: https://doorstation.co.uk/blogs/blog/standard-uk-door-sizes
• Door Superstore, UK standard door sizes and conversion chart: https://www.doorsuperstore.co.uk/help-and-advice/product-guides/internal-doors/uk-door-sizes-and-conversion-chart/
• Door Superstore, Standard door frame sizes in the UK: https://www.doorsuperstore.co.uk/help-and-advice/product-guides/door-frames/standard-door-frame-sizes-in-the-uk/
• Everest, Standard door sizes UK: https://www.everest.co.uk/doors/standard-door-sizes/
• Internal Doors, External door sizes: https://internaldoors.co.uk/blogs/news/external-door-sizes
• Wickes, 1981mm internal doors (double door pair sizes): https://www.wickes.co.uk/featured/1981-mm-internal-door
• BWF Fire Door Alliance, Best Practice Guide (fire doors tested as a complete doorset): https://firedoors.bwf.org.uk/app/uploads/sites/3/2025/10/Fire-Door-Alliance-Best-Practice-Guide-2023-8-1.pdf