Standard exterior door size: a complete guide for Canadian homeowners

Key takeaways

• The standard Canadian exterior entry door is 80" tall × 32" wide. A 36-inch door is increasingly popular in new construction because it's easier to move through and supports accessibility.
• Rough openings are about 2 inches wider and 2 inches taller than the door unit itself to allow for shimming, levelling, and squaring.
• Patio door widths vary a lot by type: sliding doors run 60 to 108 inches, French doors 60 to 72 inches, and sliding-stacking systems can exceed 192 inches for custom openings.
• Where accessibility requirements apply, the National Building Code of Canada calls for a clear opening of at least 850 mm (about 33.5 inches). A 36-inch door is typically needed to meet it.
• Standard sizes fit most post-1960 Canadian homes. Custom sizing is usually needed for heritage homes, enlarged openings, or non-standard architecture.
• Always measure the rough opening, not the old door, before ordering a replacement. Old doors are often cut down or shimmed and don't reflect the true opening size.

The most common exterior door size in Canada is 80 inches tall by 32 inches wide for a single entry door. This standard door size fits most Canadian homes built after 1960, and it's the most commonly manufactured replacement size. If you're replacing an existing door in a post-1960 home, a standard door will often fit the existing rough opening without structural changes.

Door sizing involves more than one measurement, though. The rough opening, frame dimensions, slab size, and clearance allowances all interact, and a mistake at any stage can cause installation problems. This guide covers standard dimensions for common door types in Canadian homes, how to measure correctly, and when building code or custom sizing comes into play.

Why door size matters beyond the obvious

Getting the door size right is a practical decision that affects several things at once. A door that's too narrow creates accessibility problems and may fall short of current building codes. A door that's slightly too small for its rough opening lets in drafts and reduces energy performance. And a door ordered in the wrong size means weeks of delay, sometimes with a restocking fee on top.

Safety and accessibility

The National Building Code of Canada (NBC) sets minimum door widths that vary by building type. For houses, the NBC requires entrance doors at least 810 mm (about 32 inches) wide, so a standard 32-inch door meets the basic requirement. Stricter accessibility rules, including an 850 mm (about 33.5-inch) clear opening at barrier-free doorways, apply mainly to multi-unit and public buildings and to units designated as accessible or adaptable. Provincial codes can go further, so confirm the rules with your local building department. For new construction, many homeowners choose a 36-inch front entry door for everyday comfort and future accessibility.

Fire doors in multi-unit residential buildings carry additional requirements under NBC and provincial codes, including minimum ratings, self-closing hardware, and specific frame specifications. These aren't optional and should be specified by an installer familiar with your local authority's current requirements.

Energy performance

A door that doesn't fit its opening properly allows air infiltration around the frame, the most common source of drafts in Canadian homes. The door slab itself may be well insulated, but gaps at the top, sides, or threshold from incorrect sizing or a rushed installation undermine that performance entirely. Over a Canadian winter, a poorly fitted door results in real, continuous heat loss.

Resale and code compliance

Getting sizing right at installation is far less expensive than correcting it later. If you're renovating with resale or aging in place in mind, a wider entry door can make the home easier to use for more buyers. Confirm your door choices against your provincial building code before installation.

Standard exterior door sizes in Canada

The table below covers standard dimensions for the most common exterior door configurations in Canadian residential construction. All measurements refer to the nominal door slab size. The frame and rough opening are larger, as explained in the measuring section below.

Should you choose a 32″ or 36″ entry door?

The 32-inch single-entry door has been the residential standard in Canada for decades and fits the rough openings in most existing homes. It provides adequate passage width for everyday use, but it doesn't provide the 850 mm clear opening required where accessibility rules apply.

The 36-inch door has become the preferred specification in new construction, and it's worth choosing in any renovation where the rough opening can accommodate it. It's more comfortable for everyone, including anyone using a mobility aid, moving furniture, or just carrying groceries, and it's the standard choice where an 850 mm clear opening is required. If your existing rough opening is 38 inches or wider, a 36-inch door can go in without structural changes.

For a full look at door styles and material options beyond sizing, see our Entry Doors 101 guide .

Double entry doors

Double-entry doors use two door slabs in a single frame: most commonly two 32-inch panels for 64 inches total, or two 36-inch panels for 72 inches total. One panel is typically the primary operating door, the other a secondary panel held by flush bolts and opened only when the full width is needed.

Double-entry doors need a wider rough opening and a structural header sized for the span. Confirm with a professional before specifying a double door in an existing single-door opening. Header modification is standard work for a qualified contractor, but it adds cost and time to the project.

Tall doors and non-standard heights

Standard 80-inch (6'8") height fits most Canadian residential construction built after the mid-20th century. Taller doors, 84 inches (7 feet) and 96 inches (8 feet), are available and increasingly popular in custom and luxury builds. They need a taller rough opening and a correspondingly larger structural header, built in from the start for new construction, but requiring modification in an existing home. If you're planning a taller door as part of a renovation, get a structural assessment before ordering.

Standard patio door sizes

Patio doors follow a different set of standard sizes than entry doors. For full sizing detail on sliding, French, and stacking patio doors, see our dedicated patio door size guide .

Sliding patio doors

The 72-inch (6-foot) sliding patio door is the most commonly used size for residential patio doors in Canada. It fits the rough openings in most suburban homes built from the 1970s onward and provides practical access to decks and patios without structural modification, making it a like-for-like replacement. The 60-inch version suits smaller spaces and balconies. Three-panel configurations and wider two-panel doors need larger rough openings and header spans.

French patio doors

French patio doors typically run 60 to 72 inches wide and 80 inches tall. Both panels hinge at the outer edges and open from the centre, which means they need swing clearance of roughly equal width on both the interior and exterior sides. Confirm clearance is available before specifying French patio doors; a door that only opens partway isn't functioning as designed.

If swing clearance is tight, our tilt and turn patio doors offer similar clear sightlines with a different opening mechanism.

Sliding-stacking and bifold doors

Sliding-stacking and bifold doors suit wide openings where a full-wall opening effect is the goal. These systems are custom-specified for the opening. Standard widths exist as starting points, but the final size depends on the rough opening and panel configuration. They aren't like-for-like replacements in most existing homes; they typically need structural modifications and are best planned as part of a larger renovation.

How to measure for a door replacement

The key rule: measure the rough opening, not the existing door. Existing doors are often cut down, shimmed, or otherwise modified to fit the opening at the time of original installation, so measuring the slab only tells you the dimensions of whatever was installed there, not the actual opening.

Step-by-step measurement process

Remove the interior casing (trim), if possible, to expose the rough opening edges. If you can't remove the trim, measure from the inside face of the existing door frame at the jamb.

Measure the width at three points: across the top, the middle, and the bottom of the opening. Record the smallest measurement.

Measure the height at three points: left side, centre, and right side, from the subfloor to the header. Record the smallest measurement.

Check for a square: measure corner to corner diagonally in both directions. If the two measurements differ by more than 6mm (1/4"), the opening is out of square and needs to be addressed before a new door goes in.

Check for plumb: hold a level against each side jamb. Out-of-plumb jambs need shimming during installation, so factor this into your clearance allowance.

Measure the wall depth (thickness from exterior to interior face). Standard Canadian walls run 4.5 inches (2×4 framing) or 6.5 inches (2×6 framing). Non-standard depths may need an extension jamb.

If you're replacing hardware along with the door, confirm the backset before ordering new hardware, since it's a separate measurement from the rough opening.

Rough opening allowances by door type

Once you have the rough opening measurements, subtract the allowances below to find the door size that fits the opening:

Example: a rough opening measuring 38 inches wide by 82 inches tall accommodates a standard 36-inch by 80-inch exterior door unit, with 2 inches of clearance on each dimension for shimming and levelling.

Building code requirements that affect door size

Door sizing in Canada is governed by the National Building Code (NBC) at the federal level and by provincial building codes, which may set additional or stricter requirements. The requirements most relevant to homeowners:

Accessible dwelling requirements (NBC Section 3.8)

Where Section 3.8 of the NBC applies, such as barrier-free paths in multi-unit buildings and dwelling units designated as accessible or adaptable, doorways need a clear width of at least 850 mm (about 33.5 inches) with the door open. A 36-inch door slab provides roughly 33.5 to 34 inches of clear opening, which is why it's the usual choice for these doorways. A standard 32-inch door slab provides only about 29.5 to 30 inches and falls short. Some provinces set higher minimums, and Ontario's building code, for example, calls for 860 mm.

In practical terms: if accessibility or aging in place matters for your home, specifying 36-inch doors throughout the main floor, not just the entry, is the straightforward way to plan ahead and avoid retrofit costs later.

Fire door requirements

Multi-unit residential buildings (apartment buildings, condominiums, row housing) have fire door requirements for suite entry doors, stairwell doors, and corridor doors. These are governed by NBC Division B, Part 3, and require specific fire-resistance ratings (typically 20-, 45-, or 60-minute, depending on location), self-closing hardware, and appropriate frame construction. Standard residential door products aren't fire-rated unless specifically labelled and tested. If your project involves fire doors, work with an installer familiar with the applicable code requirements for your building type.

Energy code requirements

Provincial energy codes, which implement or exceed the National Energy Code for Buildings, set maximum air leakage requirements for door assemblies. In practice, this means doors need to be properly weatherstripped and sealed at installation, which is as much a quality-of-installation issue as a product specification one. Choosing ENERGY STAR certified doors is a straightforward way to confirm the product meets a recognized national efficiency standard.

Do you need a standard or custom exterior door?

For most Canadian homeowners doing a like-for-like replacement in a post-1960 home, a standard door size is the right choice. Standard sizes are faster to get, less expensive, and easier to install. Custom sizing adds cost and lead time without adding functional value in most cases.

When custom is genuinely necessary

Custom sizing is the right call when the existing rough opening genuinely doesn't match any standard door unit, which is common in pre-war homes, heritage buildings, and homes that have settled or been modified over the years. It's also the right approach when you're enlarging an existing opening as part of a renovation, since that requires structural framing work regardless of the door size chosen.

If a contractor recommends custom sizing for a straightforward replacement in a post-1960 home without a clear explanation of why standard sizing doesn't work, get a second opinion. Most standard Canadian rough openings from the past 60 years accommodate readily available standard door units with normal shimming and adjustment.

How the Canadian climate affects exterior door size and performance

Larger doors and thermal performance

A wider or taller door has more surface area for heat to transfer through, which can be managed with proper insulation specifications. Modern insulated door slabs perform well, but the perimeter seal becomes more critical as door size increases. A larger door has more linear feet of weatherstripping that can fail, more threshold length that needs to seal against cold air, and more frame perimeter where condensation can form in cold weather if the installation isn't done correctly.

For large patio door openings in cold Canadian climates, look for ENERGY STAR certified products with a U-factor of 1.22 W/m²·K or lower, and consider triple-pane glass for the best cold-weather performance. For entry doors, an insulated core with foam-filled construction provides the insulation value; the slab itself is rarely where most energy loss occurs. The frame, threshold, and weatherstripping are the primary sources of heat loss in a door assembly.

Material choices for Canadian conditions

Canadian Choice Windows & Doors™ builds its entry doors in DraftLOCK steel with an insulated core, chosen for strength, security and durability through Canadian winters, and also offers all-wood and aluminum-clad wood doors for homeowners who want a different look. For homeowners comparing materials more broadly, here's how the main options perform in Canadian conditions:

Steel: best forced-entry resistance. Needs a powder-coat or galvanized finish to prevent rust, particularly in coastal provinces or areas with road salt exposure. A thermal break prevents condensation on the interior face in cold climates.

Fibreglass: doesn't conduct cold, doesn't rust, and handles freeze-thaw cycling without warping. Available in wood-grain finishes.

Wood needs regular maintenance in exterior applications, including painting or staining every few years and an annual inspection of the bottom rail and threshold. Better suited to protected locations than to fully exposed exterior use.

Aluminum: lightweight and contemporary, but needs a thermal break for Canadian exterior applications. Without one, the frame conducts cold and creates condensation issues in winter.

For more on how material and build quality affect long-term performance, see our guide to cheap vs. high-quality exterior doors .

Getting it right the first time

Door sizing mistakes are expensive. A door ordered in the wrong size can add weeks to a project. A door installed in an out-of-square opening without correction creates draft problems that persist for the life of the installation. A standard door specified where a custom size was genuinely needed results in a forced fit that compromises both appearance and performance.

Canadian Choice Windows & Doors™ has been helping homeowners across Canada select and install the right doors, including our steel entry doors , for over 30 years. The process is straightforward: measure the opening accurately, identify the right door unit for the application, install it to specification, and confirm it seals and operates correctly before the job is complete, all backed by our 25-year transferable warranty . If you'd rather leave the measuring to a professional, our installers can confirm rough opening measurements during a free assessment; see our comparison of DIY vs. professional entry door installation if you're weighing the two.

Frequently asked questions

What is the standard door size in Canada?

In Canada, the standard exterior entry door is 80 inches tall by 32 inches wide, with a 36-inch-wide door increasingly used to meet accessibility requirements in new construction. Double entry doors are typically two 32-inch panels (64 inches total) or two 36-inch panels (72 inches total). Patio doors follow a different set of standard sizes: sliding doors typically range from 60 to 108 inches wide, depending on the configuration. The right standard size depends on the type of door, so it's worth checking the specific tables in this guide for your situation.

What is the standard exterior door size for a single entry door?

The most common exterior single-entry door size in Canada is 80 inches tall by 32 inches wide. A 36-inch-wide door is the accessible standard and is increasingly common in new residential construction. Double entry doors are typically two 32-inch panels (64 inches total) or two 36-inch panels (72 inches total).

How much larger should the rough opening be than the door?

For a standard exterior hinged door, the rough opening should be about 2 inches wider and 2 inches taller than the door unit, to allow space for the frame, shimming, and levelling. For a 32×80 door unit, the rough opening should be about 34 inches wide by 82 inches tall. For sliding patio doors, 1 inch of clearance is typically enough.

Does a 36-inch door meet the accessibility requirement in Canada?

Generally, yes. Where accessibility rules apply, the National Building Code of Canada requires a clear opening of at least 850 mm (about 33.5 inches). A 36-inch door slab provides about 33.5 to 34 inches of clear opening, which meets this requirement, while a standard 32-inch slab provides only about 29.5 to 30 inches. Some provinces set a higher minimum, so check your local code. For homes where accessibility matters, 36-inch doors on all main-floor doorways are the practical specification.

Can I replace a 32-inch door with a 36-inch door without structural changes?

It depends on the existing rough opening. If it's 38 inches or wider, a 36-inch door unit can go into the same opening without structural modification, since the extra clearance is simply shimmed. If the rough opening is 34 to 35 inches (sized for a 32-inch door with standard clearance), widening it to fit a 36-inch unit means moving a rough opening jack stud and potentially modifying the header. That's straightforward work for a professional, but it adds cost and time.

What is the difference between a door slab and a pre-hung door?

A door slab is the panel only, with no frame or hinges attached, used when the existing frame is in good condition and only the slab needs replacing. A pre-hung door is a slab already mounted on hinges within a complete frame unit. Pre-hung doors are the standard for most replacements and new installations, since hinge alignment and frame squareness are factory-set. A slab-only replacement is faster and less expensive, but it requires the existing frame to be structurally sound, square, and plumb.

How do I know if I need a custom door size?

Measure the rough opening as described above, then compare it to the standard door sizes in the tables. If the rough opening width is within 2 inches of a standard door unit size, a standard door will fit. If the opening is significantly wider or taller than any standard unit, or narrower than 32 inches for an entry door, a custom size is likely needed. Pre-1950 Canadian homes frequently have non-standard rough openings due to the era's framing practices; post-1960 homes are almost always built to standard framing dimensions.

What size door do I need for a wheelchair or mobility aid?

A 36-inch door slab provides a clear opening of about 33.5 to 34 inches when fully open, adequate for most standard wheelchairs, which typically need 32 to 34 inches of clear passage width. Power wheelchairs and some larger mobility aids may need up to 36 inches. For any renovation or new build where accessibility is a priority, 36-inch doors on all main-floor passage points, not just the entry, are the practical minimum. Lever-style hardware is also easier to operate than round knobs for anyone with limited hand strength or grip.