Choosing the right interior door might sound simple, but it’s one of those decisions that will affect your home’s comfort, traffic flow, privacy, and even long-term resale value. Whether you’re planning a full renovation or just replacing a single slab, understanding standard interior door size, door types, and installation requirements helps you avoid costly mistakes.
This 2026 Home-Improvement–style guide walks you through everything you need to know—from standard interior door dimensions, to rough openings, to choosing between slab and prehung doors. We’ll also break down common door types, frame sizes, accessories, and installation tips.
Table of Contents
Part 1. What is the standard size of interior doors?
When we talk about standard interior door dimensions, we’re usually referring to the most common sizes for single-leaf swing doors found in residential homes. These vary slightly depending on the country, building code, and manufacturer, but several measurements are widely recognized across the market.
1. U.S. Standard Interior Door Sizes (Most Common)
In the United States, interior door sizes are expressed in inches, and the most common size is:
Height: 80 inches (6 ft. 8 in.)
Width: 24″, 28″, 30″, 32″, and 36″
Here’s the typical range:
| Feature | Standard Size |
| Standard Height | 80″ (2032 mm) |
| Tall Door Options | 84″ (2134 mm) or 96″ (2438 mm) |
| Common Widths | 24″, 28″, 30″, 32″, 36″ |
| Thickness (slab) | 1-3/8″ (35 mm) standard interior; 1-3/4″ for solid-core or fire-rated |
Note: 24″ and 28″ doors are commonly used for bathrooms, closets, and laundry rooms.
36″ doors are often used for accessibility or main passageways.
2. Europe / U.K. Standard Interior Door Sizes
| Region | Standard Width | Standard Height |
| EU (general) | 626 mm, 726 mm, 826 mm, 926 mm | 2040 mm |
| U.K. | 610 mm, 686 mm, 762 mm, 838 mm | 1981 mm or 2040 mm |
3. Typical Interior Door Dimensions in Metric Units
| Region | Standard Width |
| EU (general) | 626 mm, 726 mm, 826 mm, 926 mm |
| U.K. | 610 mm, 686 mm, 762 mm, 838 mm |
| U.K. | 610 mm, 686 mm, 762 mm, 838 mm |
Most commonly used:
Width: 800–900 mm
Height: 2000–2100 mm
4. Standard Sizes for Special Use Cases
24-inch solid core door → Often used for small bathrooms where privacy + sound insulation matters.
36-inch door → Common for ADA accessibility and wider entryways.
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Part 2. Types of Interior Doors (With Standard Dimensions, Pros/Cons & Uses)
Homeowners today have more design options than ever. Each door type offers different benefits depending on your space, layout, and budget. Below is a Home-Depot–style breakdown of the most common interior doors.
2.1 Hinged Door
This is the most traditional option and the basis for the standard interior door size. Fixed to the frame by hinges on one side, it offers the best acoustic and thermal insulation thanks to the complete seal when closed. Its main disadvantage is the need for a clear opening radius, or swing, which can limit furniture placement in small rooms.
Typical U.S. dimensions:
Width: 24″, 28″, 30″, 32″, 36″
Height: 80″, 84″, 96″
Thickness: 1-3/8″ slab standard
Best for: Bedrooms, bathrooms, home offices, and most interior applications.
Advantages:
• Best sound insulation of all door types
• Easy to operate & repair
• Works with many hardware options
Disadvantages:
• Requires swing clearance
• Furniture placement may be limited
2.2 Sliding Door
It moves on tracks above the opening and does not require floor space to open. It is ideal for closets or large openings where acoustic insulation is not a priority. It offers a clean solution but the track may sometimes be visible and insulation is reduced.
Common sizes:
60″–72″ wide for closets
Single 30″–36″ panels for room dividers
Best for: Closets, small rooms, contemporary spaces.
Contact Us for a Project Consultation
Why pay more? At George’s Furniture, we cut out the middlemen to bring you premium furniture, flooring, doors, windows, and more—all at prices up to 40% below retail. With 19+ years of experience and 600 consultants, we provide complete, custom project solutions, from initial design to final delivery.
Advantages:
• Saves floor space
• Clean, modern look
• Great for wide closets
Disadvantages:
• Lower sound insulation
• Tracks need maintenance
2.3 Barn Door
This is a sliding door with a completely exposed track mechanism in a rustic or industrial style, commonly known as a barn door. It creates a strong visual impact and does not interfere with the doorway, but it requires the adjacent wall to be completely clear for sliding and does not seal the opening.
Typical dimensions:
Width: 36″–48″ single panel
Height: 84″–96″
Advantages:
• Very stylish focal point
• Saves floor space
• Simple DIY installation
Disadvantages:
• Does not fully seal (sound & privacy limited)
• Requires large wall space beside the opening
2.4 Pocket Door
It moves on tracks above the opening and does not require floor space to open. It is ideal for closets or large openings where acoustic insulation is not a priority. It offers a clean solution but the track may sometimes be visible and insulation is reduced.
Standard sizes:
Same slab sizes as hinged doors: 28″–36″
Height: 80″–96″
Advantages:
• Best space-saving option
• Ideal for tight bathrooms or utility rooms
Disadvantages:
• Cannot mount plumbing/electrical on pocket wall
• Installation is more complex
• Repairs require partial wall removal
2.5 French Door
It consists of a pair of hinged doors that open from the center, often with glass panels. These doors maximize natural light and create a sense of grandeur, but they require double the swing space of a single door.
2.6 Bifold Door
Composed of two or more hinged panels that fold onto themselves, it is excellent for wide closures such as those of closets or laundry rooms, occupying minimal opening space compared to a hinged door.
Common sizes:
Width: 24″, 30″, 36″, 48″, 60″, 72″
Height: 80″
Advantages:
• Ideal for closets & laundry areas
• Saves swing clearance
• Budget-friendly
Disadvantages:
• Not suitable for privacy
• Hardware can wear out over time
For a quick consultation of the typical interior door dimensions, refer to the following table:
| Door Type | Standard Dimensions (mm) | Standard Dimensions (inches) | Advantages | Disadvantages |
| Hinged Door | 800/900 x 2000/2100 | 32/36 x 80 | Best insulation and sealing. | Requires free swing space. |
| Sliding Door | 800/900 x 2000/2100 (Single) | 32/36 x 80 (Single) | Requires no floor space. | Reduced acoustic insulation. |
| Pocket Door | 800/900 x 2000/2100 | 32/36 x 80 | Maximum space optimization. | Complex installation, internal wall inaccessible. |
Part 3. Door Slab Size vs. Frame vs. Rough Opening
It is essential to understand that the width of the interior door opening is not a single measurement. There are three interconnected measurements that determine fit and correct installation.
Contact Us for a Project Consultation
Why pay more? At George’s Furniture, we cut out the middlemen to bring you premium furniture, flooring, doors, windows, and more—all at prices up to 40% below retail. With 19+ years of experience and 600 consultants, we provide complete, custom project solutions, from initial design to final delivery.
3.1 Door Slab Size
This is the measurement of the moving panel only, the physical element that opens and closes. If a door is described as 32 inches, that measurement refers to the width of the slab only.
3.2 Door Frame Size / Finished Door Size
This is the standard interior door frame size complete. It includes the slab, the side uprights (jambs), the header, and the hinges. The finished frame represents the actual overall size of the product that must be inserted into the wall.
A typical frame adds:
+1″ to +2″ in width
+1/2″ to +1″ in height
Example:
A 30″ x 80″ slab becomes a 31.5″ x 81″ finished frame, depending on jamb thickness.
3.3 Rough Opening / Doorway Opening
The rough opening is the structural opening made by the carpenter in the wall. It must intentionally be larger than the finished frame. This extra space is necessary to allow the installer to set the frame perfectly plumb and level, using shims to compensate for the inevitable imperfections of the wall structure.
The width of the interior door opening (or doorway width) is the net width of the opening between the jambs once the frame is installed. It is always less than the nominal width of the slab.
To illustrate the dimensional hierarchy, observe the comparative table for a standard American model of 32 inches X 80 inches:
| Measurement Type | Width (inches) | Height (inches) | Notes |
| Slab (Door Slab) | 32 | 80 | Nominal panel measurement. |
| Frame (Door Frame) | Approx. 33.5 | Approx. 81.5 | Slab + Jambs; the product’s overall size. |
| Rough Opening | Approx. 34 | Approx. 82 | The hole in the wall; larger than the frame for tolerance. |
3.4 How These Measurements Relate
Door slab = panel only
Finished frame = slab + jambs + hinge allowance
Rough opening = space needed in wall to fit frame
In simple terms:
Rough Opening > Frame Size > Door Slab
Part 4. Slab Door vs. Prehung Door
The choice between a slab door and a prehung door is a crucial decision that affects costs and installation complexity.
Slab Door Explained Simply
A Slab Door is just the door panel itself—no frame, no hardware, and no holes drilled for hinges or handles.
You usually buy it when you only want to replace an old door inside an existing frame. While the initial cost is lower, be aware: installing it requires high skill because everything (drilling, fitting hinges) must be done on-site, increasing the risk of mistakes.
Pros:
• Cheapest option
• Great when reusing existing frames
• Easy to paint or customize
Cons:
• Requires carpentry skills
• Must align with existing hinge positions
• Bore holes may need drilling
Prehung Doors: The Easy Option
It’s a full unit with the door slab already mounted to its frame, hinges installed, and holes pre-cut for your handle.
This is the standard, best choice for new builds or replacing everything.
The huge advantage? Installation is quick and simple. Since the door and frame are perfectly aligned from the factory, you just fit the whole unit into the rough opening.
Pros:
• Easiest for new construction
• Guaranteed alignment
• Faster installation
Cons:
• More expensive
• Heavier
• Harder to transport
| Feature | Slab | Prehung |
|---|---|---|
| Cost | $ | $$–$$$ |
| Installation Difficulty | High | Low |
| Includes Frame | No | Yes |
| Ideal For | Replacements | New openings / full remodel |
Part 5. Door Accessories
Accessories improve performance, durability, and ease of use. Choosing the right ones ensures your door fits and functions properly.
5.1 Hinges
Standard interior doors use:
3 hinges for 80″ doors
4 hinges for 96″ tall doors
Material options: brass, nickel, black, chrome.
5.2 Locksets / Handles
Types include:
Privacy (bathroom/bedroom)
Passage (hallway/living room)
Dummy (closets)
Standard backset:
2-3/8″ (most common)
2-3/4″ (for deeper handles)
5.3 Weatherstripping / Seals
Even interior doors can benefit—especially bathrooms and bedrooms—for sound reduction.
5.4 Door Jambs
Standard jamb depth matches wall thickness:
4-9/16″ for 2×4 stud walls
6-9/16″ for 2×6 walls
5.5 Casing / Trim
Decorative frame that covers gaps between the wall and door frame.
Part 6. Door Installation Checklist
Proper installation ensures your door opens smoothly and avoids rubbing or drafts. It truly verifies the accuracy of your measurements!
Key Checks:
Rough Opening (RO) Size: Make sure the RO provides the necessary $1/2″$ to $1″$ tolerance around the finished frame for leveling and shimming.
Finished Wall Thickness: The jamb depth must match your finished wall thickness (including drywall). Don’t just focus on the width!
Floor Level: Ensure adequate clearance (approx. $1/2″$ to $3/4″$) beneath the slab to prevent scraping, especially if installing new flooring.
Handing: Plan the swing direction so the open door doesn’t block switches or traffic flow.
FAQ
Q1 . What are non-standard interior doors?
These are doors with dimensions that do not fall within common market measurements. They are used to adapt to unique architecture, historic buildings, or when an interior door opening width greater than 36 inches is required for specific accessibility needs.
Q2. How thick is a door slab?
Standard interior slab: 1-3/8″ (35 mm)
Solid-core / fire-rated: 1-3/4″ (45 mm)
Q3. What is the most common interior door?
In the U.S., the most common size is: 30″ × 80″ single hinged door
Q4. Is a 30-inch door truly 30 inches?
Yes—this refers to the slab width. The finished frame and rough opening will be larger.
Q5. Are most doors 36 inches wide?
No, 36 inches (914 mm) is not the most common size, but it is the width of interior doors often used for hallways and main entrances to ensure accessibility (ADA regulations).
Q6. What is the standard interior door frame size?
The standard interior door frame size is approximately 1.5 inches (38 mm) wider and 1.5 inches taller than the nominal slab (32 inches) to accommodate the jambs and tolerance space.
Q7. What is the width of the interior door opening?
The width of the interior door opening (doorway width) is the net width, from jamb to jamb, which corresponds to the actual usable passage space, a value always slightly less than the nominal slab width.
Conclusion
Choosing the right interior door is an investment that goes beyond aesthetics. Understanding the standard dimensions, distinguishing between the door slab and the frame, and knowing the various door types available (hinged, sliding, pocket) is essential to ensure a flawless final result. By carefully evaluating the width of the interior door opening and the function of the room, you can avoid purchasing costly non-standard doors.
For a perfect fit and style, explore George’s Furniture. They offer a wide variety of door styles and custom sizing options. Visit George’s Furniture today to find the ideal size and style tailored to your home, improving the comfort, security, and harmony of every space!
Contact Us for a Project Consultation
Why pay more? At George’s Furniture, we cut out the middlemen to bring you premium furniture, flooring, doors, windows, and more—all at prices up to 40% below retail. With 19+ years of experience and 600 consultants, we provide complete, custom project solutions, from initial design to final delivery.
