Get all the information you need to choose perfectly sized interior doors for your new home or remodeling project.


You probably haven’t given much thought to the size of the doors in your home, unless you have one or two that are either so big or so small that they don’t function well or look out of place. This article discusses how the sizes of the doors in a home can affect safety, traffic flow, furniture placement, trim profiles, and overall aesthetics.

How Wide Should an Interior Door Be?

The width of doors has traditionally been described by manufacturers, retailers, and carpenters in feet and inches instead of just inches. That means a door that is 30 inches wide might be referred to as a 2/4, as in 2 feet x 4 inches. wide. The most common interior door widths are 2/0, 2/4, 2/6, 2/8 and 3/0, which translates to 24, 28, 30, 32, and 36 inches wide.


Before exploring how wide an interior door should be, let's discuss how wide a door is required to be. The International Residential Code (IRC) has specific minimum size requirements for exterior doors. These building codes are designed to ensure that first responders, often weighed down with bulky equipment, can quickly get into a home in case of an emergency. And while the IRC has no specific requirements or restrictions on interior doors, not every state follows every provision in the IRC. Some states reject certain IRC requirements, and some add their own. There are certain states that have added more stringent building codes that regulate interior door sizes. The state of Michigan, for example, restricts interior doors to no less than 24 inches, unless they lead into a room with a floor space less than 10 feet, like a closet, or small bathroom. Before you build, or plan that remodel project, check with the local building officials to find out if there are restrictions on smaller doors in your area.

How Thick Should an Interior Door Be?

Most interior doors are either going to be 1 3/8 inches or 1 3/4 inches thick. And of those two sizes 1 3/8 is much more common. All other things being equal, a thinner door will be less expensive. Thicker, solid core doors have a few advantages. First, they feel substantial and more solidly built and convey a feeling of quality and superior craftsmanship. A thicker, solid core door protects better against forced entry, which is typically more of a concern for exterior doors, but for some, a stout interior door can also add a sense of security. And finally, a thicker door will reduce the amount of sound transferred from one room to another. Most doorknobs and handles are made to fit both standard door sizes, but if you’re thinking about building a custom door, you’ll have fewer hardware options if you stray outside those measurements.

Plenty of Space for Creativity

For large spaces, consider adding a pair of French doors. You can bring natural light further indoors and expand the height of the door without increasing the size of the door by adding a transom window above. To make existing doors feel bigger, you could build a decorative panel above the door and add to the width of your casing trim. Separate a large public area into two private rooms for guests by combining multiple large doors to a sliding door system. If the size of your space doesn’t affect the function of your door, there is very little preventing you from designing the exact door size you want.

Why TruStile, a Marvin Brand

Marvin has been an industry leading window and exterior door manufacturer for nearly 100 years. In 2015 Marvin acquired TruStile, a brand known to bring the same commitment for excellence to the interior door space as Marvin delivers in its windows and doors. Just like Marvin products, TruStile interior doors are only found at experienced supply partners with unrivaled local building expertise. TruStile partners specialize in serving contractors, home builders, architects, and design professionals who understand that it takes well-designed, heirloom-quality products to create truly special spaces for their clients. Both Marvin and TruStile are passionate about innovation and imagining new ways to help people feel healthier and happier in the spaces where they live, work, and play.