Choosing the right interior door is about more than just aesthetics—it’s about ensuring a proper fit for functionality and durability. Whether you’re replacing an existing door or installing a new one, understanding standard door dimensions is crucial. Additionally, in cases where standard sizes don’t fit, you may need to trim a door or opt for a custom-sized one. In this guide, we’ll break down standard interior door sizes, when trimming is appropriate, and why custom doors might be the best solution for your space.
What Are Standard Interior Door Dimensions?
When choosing an interior door, it’s essential to understand standard door dimensions to ensure the perfect fit. Doors are typically measured in inches or feet, following the sequence: width, height, and thickness. Knowing these standard measurements will help you select the right door for your space or determine if you need a custom-sized door.
Standard Interior Door Sizes
Width
- Standard interior door widths range from 12” to 42”.
- Widths increase in 2-inch increments, meaning common door sizes include 26”, 28”, 30”, 32”, and so on.
- If you require a width that falls between these standard measurements, it will be considered a custom door size.
Height
- Interior doors come in four standard heights:
- 80” (most common for residential applications)
- 84” (for taller spaces)
- 90” (a little extra height)
- 96” (for high-ceiling applications)
- Any height outside of these standards will require a custom-made door.
Thickness
- Most interior doors come in either 1 3/8” or 1 3/4” thick.
- A general rule of thumb:
- 1-3/8” thick doors are suitable for 80” and 84” tall doors.
- 1-3/4” thick doors provide better stability and are recommended for 90” and 96” tall doors.
- Retrofit/ renovation and you are using the existing jambs, follow what was existing.
If your space does not accommodate a standard door size, don’t worry. Many renovations and retrofits require custom doors, and companies like Royal Door and Trim Supplies offer both standard stock doors and custom-made options to fit any opening.
