How Are Garage Doors Measured? Quick & Easy Homeowners Guide

Using a measuring tape is one of the ways on how are garage doors measured.

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Whether you’re looking to install a door to your new garage or replace an old one, ordering the right size garage door is important. Failure to obtain accurate measurements could lead to unnecessary labor and order expenses. 

While measuring a garage door is not complex, it can be challenging without proper guidance. 

This article offers a simple and comprehensive guide on how are garage doors measured. You’ll learn how to accurately measure the door’s width, height, and surface area. Let’s get started and make measuring your garage door a breeze.

How Are Garage Doors Measured?

Measuring a garage door is a simple process. However, there are a few important considerations to keep in mind so that you can get accurate readings. But before we explain the process in detail, here are a few important tips to remember.

Tips Before Starting

A measuring tape and how to use it. These are tips before measuring a garage door.

Before you begin measuring your garage door, we have some tips in store for you.

  • Clear anything that might obstruct your way, including pipes, electrical wiring, and other objects. With obstructions in the way, you might get inaccurate readings and end up ordering the wrong size.
  • Take multiple measurements to avoid miscalculations. Make sure you take at least 3 measurements to confirm the readings are accurate. Verification of the measurements will take less time than the time you’ll need to send the wrong-sized garage door back. 
  • Use a high-quality measuring tape. If your old tape has blurry lines or is barely hanging by a thread, we suggest you purchase a new one. Plus, the measuring tape you use must be long enough to reach the highest point of your garage door. 
  • Don’t forget to measure the headroom, backroom, and side room. 
  • If you sense that these instructions are beyond your skill set, look for a professional garage door installer and leave the technical work to them.

Step 1: Measuring Opening Width

Measure the width when measuring a garage door.

Once you’ve got your measuring tape and ladder (to help measure the height), clear all the obstructions and measure the opening width of your garage door. Here’s how:

Take your measuring tape and measure the width of the garage door from the inside edges of the garage door opening up to the widest point. Your garage door’s widest point is most likely at the bottom of its opening.

Check at multiple points to decrease the chances of getting the wrong reading. The opening width should not be too narrow or too wide, as it can leave gaps, creating an opening for pests, animals, or even rain from entering.

Once the measurement is complete, note it down.

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Step 2: Measure the Opening Height

Measure the height when measuring a garage door.

After measuring the opening width, measure your garage door height from the floor right to the top of the garage door opening. You will find the high point (top of the garage door opening) at the center of the opening, where the door intersects with the header, or at the point where your ceiling crosses the wall.

For greater accuracy, measure the opening height from multiple angles. If needed, you can round up the measurement to the nearest inch. Inaccurate readings can result in buying a door of the wrong size, so it is crucial to take multiple readings and ensure precise measurement of the garage door height.

Step 3: Measure Depth

Measure the depth when measuring a garage door

Measuring the depth of the garage door allows you to ensure there is sufficient space for the garage door hardware and tracks. You can calculate the depth by measuring the distance from the front of your garage opening to the backside of your garage, where the garage door lands upon closure.

Step 4: Measure Headroom

Measure the headroom when measuring a garage door.

 The garage door headroom refers to the space above the garage door opening. Accurate headroom measurement allows the door to work smoothly without hitting the ceiling or other obstructions above the garage door.

To measure the headroom:

  1. Take your measuring tape and measure the exact distance between the ceiling and the floor of your garage. This is the total height that the garage door will work in.
  2. Now calculate the space the garage door’s track and hardware will use. To do that, simply measure the distance from the ceiling to the top of the opening.
  3. Lastly, measure the distance from the rear of the opening to the closest object that may obstruct its path (such as a beam). This is necessary because it will help calculate the garage door track’s radius size.

Most garage doors need at least 12 inches of headroom so the door can work easily. However, if you have a narrow headspace, you can go with low-headroom tracks that will fit in if you have tight spaces.

Step 5: Measure the Side Room

Measure the sideroom when measuring a garage door.

The side room is the area between the nearest wall and the garage door’s opening. Measuring the side room is important because it helps to let you know the space that will accommodate the garage door’s tracks and hardware.

To measure your garage door side room:

Take a measuring tape and measure the distance between the nearest wall and the inside edge of your garage opening. To ensure that the measurement is precise, take measurements from multiple sides.

Step 6: Measure the Backroom

Measure the backroom when measuring a garage door.

The garage door backroom is the area from the back of the opening to the wall of your garage. You need to measure this area to ensure sufficient space for the garage door hardware. Your garage door should have enough backroom space for the garage door to fully open and close (without obstructions).

Inaccurate backroom measurement poses a safety hazard. When the garage door does not open or close properly, it may harm or injure the one near it. That is why it is important to follow the measurement process accurately.

 To measure the garage door backroom:

  1. Stand right at the center of your garage door opening and turn your face towards the interior of the garage.
  2. Measure the distance from where you are standing to the back wall of the garage.
  3. Verify your readings using the same point to measure both sides of the garage door. Record the measurements.

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What Are The Most Common Sizes of Garage Doors?

For your convenience, here’s a table of the most common garage door sizes found in America (if the size of your garage door is different, you might need a custom-sized garage door):

Types of Garage DoorWidthHeight
Single Vehicle Garage Door8 Feet7-8 feet
Double Vehicle Garage Door16 Feet7-8 Feet
RV Garage Door12-14 Feet12-14 Feet
Standard7 Feet8 Feet

When Should You Ask For Professional Assistance?

Measuring a garage door is a detail-oriented task that requires precise measurements so you don’t order the wrong garage door. If you don’t have prior experience in measuring a garage door or if you are not handy with tools, you should rely on the experts to measure your garage door for you.

Hiring a qualified and experienced garage door technician ensures accurate measurements. On top of this, they can also fix or repair issues pertaining to your garage door (if any).

To aid you in budgeting, we’ve created a table comparing the costs of hiring professionals (figures may vary depending on the place you live).

Table Comparing Different Costs of Garage Experts

Type of WorkEstimated Cost
Measuring garage door$50-150
New door installation$700-1500

Final Thoughts

If you are looking for a convenient garage door replacement or installation, you can simply follow the steps that we went through in this article. Getting precise measurements is the most important. It may look like a lot of work, but if you strike the right measurements properly, you will have the perfect fit with your new garage door.

But if you’re having trouble getting precise readings, it’s best to seek professional help to avoid problems associated with ordering the wrong size.

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Daniel Walter

Daniel Walter is a garage door expert with 15+ years hands-on experience and a degree in mechanical engineering. He's on a mission to empower homeowners with all the knowledge they need to tackle any garage-related issue with ease. When he's not sharing his expertise, you can find him scaling mountains and basking in the beauty of the great outdoors.

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