The Anatomy of the Standard Door Width

Standard Door Width

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You might be interested in knowing the standard door width for a variety of reasons. Whether you’re remodeling your home, restoring a historic apartment, or building a new home, it can be helpful to be familiar with the dimensions of pre-made doors.  

Read on for everything you need to know about the typical width of modern doors. 

Standard Interior Door Width

An interior door is obviously any door inside your house except for those exiting to the outside. In most modern homes in the United States, the interior doors will be 32 inches (813 mm) wide.

Doors to certain rooms, such as storage closets or laundry rooms, can be narrower. These doors tend to range in size from 24 inches, 28 inches, and 30 inches. Doors as wide as 36 inches are also common to meet the Americans with Disabilities Act (ADA) requirements.

TIP: to calculate a rough opening size for a particular door, simply add two inches to the width of the door and 2-1/2 inches to the height to account for the frame thickness. So the rough opening width for a 32 inch door would be 34 inches.

What is the International Building Code? 

The International Building Code, or IBC, lays out the regulations used for most commercial buildings. It belongs to the International Code Council (ICC), a global organization that publishes code standards for buildings, building accessories, and building maintenance. Its counterpart is the International Residential Code, or IRC, that establishes rules for residential homes. 

Note that there is a difference between the minimum required clear width as determined by the International Building Code and the actual dimensions of the door itself.

The “clear width” is measured between the face of the door and the stop, with the door open 90 degrees as shown below. Please consult with a professional regarding code requirements.

Clear Door Width

What is the IRC? 

The International Residential Code, or IRC, lays out regulations for residential homes and new construction. Builders who are constructing a new townhome, one-family home, or two-family dwelling will likely need to reference the IRC. It also provides the code that is generally referenced for performing renovations on your existing home. 

While the IBC, IRC, and ICC are foundational codes used universally, most states and municipalities have adopted their own version of the code. Check with your local government or permitting office to learn about the current regulations regarding standard door width or any other code-related issue. 

Standard Front Door Size 

Front doors, also called entry doors, are generally slightly wider and thicker than the doors you use inside your home. This more robust design is to provide additional security from break-ins and insulation from the elements.

To provide adequate clearance, entry doors are typically around 36 inches wide, 80 inches tall, and 1.75 inches thick. Using a larger front door can also give you more flexibility when it comes to moving furniture in and out of your home.

A Note on Door Size in Older Homes

Older homes aren’t always predictable in terms of door sizes. The two modern building codes (the IBC and IRC) weren’t published until 2000, so if your home was built before then, your doors may be oddly sized.

Measure the door you want to replace to see if it is a standard width. If not, call around to local construction yards to see if they have a door in your size. You can also purchase a slab door and cut it down to size. Or, you can order a custom door — though be aware that custom doors are usually more expensive and can take some time to arrive. 

A Short Guide to Different Types of Doors

Are you thinking about replacing a front door or sliding door to the patio? Or are you tired of bumping into the laundry room door every time you round the corner? Here are a few unique door styles that can replace your standard door. 

The Dutch Door

A dutch door is split horizontally in the middle. You can open the bottom half or top half of your door by itself. This type of door is definitely less common, but it can work well in farmhouses, with pets, and with young children. It’s a good way to let air and light into the house while keeping pets and young ones inside. 

The French Door

French doors are double doors with glass panes. They typically open inward, and they’re extremely popular in modern homes because they allow lots of light to shine in. Another benefit is that they can be used as interior or exterior doors.

If you’re thinking about installing French doors, keep in mind that insulation can be a problem. Homeowners who live in cold climates should purchase high-quality glass panes. 

The Sliding Barn Door

Sliding barn doors are heavy, durable, and provide a rustic touch to modern homes. They use hardware kits to mount above a door opening, and they slide outward along the wall to open. This keeps them from swinging into a room and taking up floor space, so they’re a good accessory for small spaces. 

The Pocket Door 

A pocket door comes with a latch on one side that functions as a handle. It is a great choice for compact apartments or small rooms, because the door doesn’t take up any floor space when it is open.

The Bifold Door 

Bifold doors slide outward and fold in the middle. They are typically used for closets and laundry rooms. But in modern homes, they’re becoming a popular choice to open onto patios or to separate rooms. 

Like the pocket door, the bifold door is a good way to save space. It comes in different configurations, such as these 6-fold doors that can be opened in a series. 

Should I Choose a Pre-Hung Door or a Slab Door?

Pre-hung doors come with their own frame and hinges. They’re easy to install because they arrive with everything you need to set them up. 

A slab door is just the door itself. You will need to purchase the hardware, frame, and hinges separately. Because of this, they tend to be cheaper.

For most homeowners and non-professionals, pre-hung doors are the better choice. You will also want to purchase a pre-hung door if this is new construction. However, you can choose a slab door if the new door has exactly the same dimensions and hinge locations as the old door.

When you’re buying a pre-hung door, keep in mind that it’s better for your door to be slightly too small rather than slightly too big. It’s much easier to install a few shims to make the door fit properly when it is too small. If the door is too big, you’ll have to remove part of the frame/wall itself. This can mess with the structure of your home, and you shouldn’t do it without consulting a professional. 

Now that you’re familiar with standard door width and the different types of doors, you’re on your way to a successful home renovation or construction project. 

Brandon Hubbard, AIA, NCARB, LEED AP BD+C