If you want the perfect replacement garage door, you need to make sure everything goes right and it all starts with the measurements. While there’s no definitive size for a garage door, there are a few traditional measurements:

  • Single garage doors: 8-feet by 7-feet, 9-feet by 7-feet, or 10-feet by 7-feet. 
  • Double garage doors: 12-feet by 7-feet, 14-feet by 7-feet, or 16-feet by 7-feet. 

Now that you have an idea of the standard sizes of garage doors, it’s time to start the measuring process. It’s important to double check everything you’re about to do because your door measurements are crucial to getting the perfect garage door and ensuring proper fit. 

It’s important to note that all these measurements are taken from the inside of your garage. Let’s get started!

4 Simple Steps to Get Your Garage Door Measurements

Before you start – make sure you are taking all measurements from inside your garage.

1. Door Opening

Measure the height and width of the door opening. Measure from the inside of the door jamb and don’t include the door jamb in your dimensions. This measurement determines the size of garage door you’ll need, and whether you’ll need to order a standard- or custom-sized door.

Door Opening Measurement
Side Room Measurement

2. Side Room

The next step is measuring the side room on both sides of the door opening. Again, start your measurements outside of the door jamb and measure to the wall. This measurement ensures there’s enough room for the vertical portion of the garage door track. In most cases, you’ll need 3 ½-inches to 4-inches of space on either side.

3. Headroom

Measuring the headroom means the space starting above the door opening and runs to the ceiling or the underside of joists or rafters above. The necessary space differs based on the type of garage door you’re purchasing.

Headroom Measurement
Backroom Measurement

4. Backroom

The final step involves measuring the garage’s backroom. The backroom is the depth of your garage. This is measured, along the ceiling, from the door opening to the farthest point at the rear of the garage. This measurement makes sure there’s enough space for the horizontal portion of the door track.

Tips for Multiple Garage Door Measurements

If your garage was built to include multiple doors, keep these tips in mind when taking measurements: 

  • Measure each door individually — even if you believe they’re all the same size, there may be small differences. 
  • If you have a two-door or three-door garage, the side room between two doors should be at least 10-inches wide to accommodate side tracks for both doors.
  • Measure the backroom for each individual door — don’t assume they’ll be the same.

What Are The Standard Garage Door Sizes? 

Several single- and double-door sizes are considered standard, such as:

  • Single doors are usually 8-, 9- or 10-feet wide. Occasionally single doors might be 12-feet wide.
  • Double doors are usually 16- or 18-feet wide, but occasionally only 14-feet wide.
  • All overhead doors are usually 7-, 8- or 9-feet high. 

But, don’t be concerned if your door measurements don’t exactly match up to a standard size. Custom doors can be designed to match your garage’s individual specifications.