Measuring your garage door is crucial whether you’re renovating your garage to create more space, replacing an old door or building a garage from scratch. Getting accurate dimensions makes it easier to find the perfect garage door you need, reduces stress during installation and saves you lots of cash. However, measuring your garage door might be challenging.

Garage doors serve multiple purposes, so it’s important to get things right when choosing and installing one. We’ve provided four simple steps to guide you in measuring your garage door correctly. We’ll also point out essential tips for measuring garage doors, go over common garage door sizes and answer the frequently asked questions that come our way.

Request an Estimate 

Steps for Measuring Your New Garage Door

Whether you’re looking to install a Clopay®, AMARR® or Wayne Dalton garage door, the following diagrams and instructions will help you get accurate measurements:

1. Secure the Necessary Tools

The first thing to do when measuring a garage door is to secure a tape measure, a writing utensil and a notepad or any tool or gadget you can use to record and store the measurements. A 25-foot tape measure is recommended to help you get accurate measurements without stopping midway to make marks and continue. It’ll also help to have an extra hand to assist with holding one end of the tape measure or writing the measurements you take during the process.

2. Find the Length and Height

Find the length and height of your rough opening — labeled 1 and 2 on the diagram — to determine what size garage door you need. Measure from the two widest points of your garage door opening. The door’s rough opening will be slightly larger than the door you’ll need. A finished opening should equal the size you need.

3. Find the Width of the Sideroom

Your garage door’s new track should fit in the areas to the sides of the garage door opening. Measure the wall strip on your garage door’s side margins — labeled 3 and 4 on the diagram. You’ll need a minimum of 3 ¾ inches per side to install the track for a standard torsion spring, standard extension spring and the EZ-SET® Torsion Spring System. You’ll need at least 5 ½ inches for the EZ-SET® Extension Spring System.

If you are installing doors for a two-door garage, the center post between both doors will need double the distance. This space should be at least 7 ½ inches for a standard extension or torsion spring or the EZ-SET® Torsion Spring System. For the EZ-SET® Extension Spring System, you will need at least 11 inches.

4. Measure the Height of the Headroom

Take the dimensions of the headroom — marked 5 on the diagram. The headroom is the space between the jamb header — or the area above the doorway — and the floor joist, or ceiling. You’ll have to adjust your measurement if you find an obstruction on your ceilings, such as pipes or light fixtures. Find the measurement between the top of the door and the bottom of the obstruction. You’ll need 10 inches of headroom for the EZ-SET® Extension Spring System or the standard extension spring. 

For a standard torsion spring and the EZ-SET® Torsion Spring System, you’ll need at least 12 inches of headroom. For garages with limited headroom, a specialized kit is available. You’ll also need additional headroom to install an automatic garage door opener.

If the height of your garage door stretches above the opening, measure your headroom from the top.

5. Measure the Depth of the Backroom

Find the dimensions of the backroom — labeled 6 on the drawing. The backroom — or the rear clearance — is the space between the overhead door and the back of the wall where you install the overhead door. 

Start at the opening of your garage door, and measure toward the back of the garage. The backroom ends at the first obstruction or when your tape measure reaches the back wall. 

The amount of backroom you need depends on the height of the garage door you buy. To have an adequate backroom, you’ll need a depth equal to 18 inches plus your garage door height. You may need additional backroom to install an automatic garage door opener, usually about 4 feet and 2 inches.

Garage Door Measurement Tips

When following this garage door measuring guide, there are several things you can do to get the most accurate measurement. Following these tips can help you catch any issues the garage door installer should be aware of:

  1. Measure to the closest fraction of an inch.
  2. Consider taking each measurement from a few different places. When you get the same number several times for each dimension, you can be confident you have an accurate number.
  3. Locate the nearest electrical outlet to install the garage door opener.
  4. Note any potential obstructions, such as light fixtures, ductwork, pipes or staircases.
  5. Examine the door jambs and the header to check their condition. If anything is uneven or unstable, it may need replacement.
  6. Check if the floor is level. An uneven floor might mean your previous door was a custom fit.
  7. Note that although the garage door measurements are usually the same standard size, they may differ depending on the type of garage door you’re planning to install.
  8. The thickness of the material used in making the garage door may also alter the standard dimensions slightly. Ensure your measurements are in accordance with the material that you wish to replace your door with.
  9. Take your time. The process is simple, but it helps not to rush. When you rush, the measurements might be inaccurate.
  10. It helps to seek professional assistance if you cannot take proper door measurements. The primary aim is to find the measurements to help you secure the perfect fit. Garage door experts can take the load off your shoulders and offer accurate dimensions while you focus on other important activities.

Common Garage Door Sizes

Generally, there are three different garage door sizes to choose from:

  • Single Garage Doors: The three standard garage door sizes are 10-by-7 feet, 9-by-7 feet and 8-by-7 feet. Standard 10 and 9-foot garage doors are suitable for standard homes and cars. Eight-foot garages aren’t usually installed in new houses today but are readily available for older homes with this size opening. 
  • Double Garage Doors: The standard sizes for double garage doors are 16-by-7 feet, 14-by-7 feet and 12-by-7 feet. Clopay® garage doors also come in 15-foot, 15-foot 6 inches, and 18-foot door lengths. This makes them suitable for large vehicles, work trucks, multi-car garages and garages with lots of storage space.
  • Custom Garage Doors: Custom-sized garage doors are built upon request. If you are building a custom size garage, renovating your existing garage or looking to fit a garage door opening with non-standard dimensions, you will be best off with a custom-fitted garage door. Some Clopay® models can be custom-ordered in length increments of 2 inches and height increments of 3 inches and could also work for uneven or sloped garage floors. 

Frequently Asked Questions

Consider these frequently asked questions about how to measure a garage door:

1. How Do I Know What Size Garage Door to Buy?

Typically, a single-garage door is 8 feet wide. Some are 9 feet wide to allow for extra clearance. You may need a 15-foot or 16-foot garage door for a standard two-car garage. For a standard three-car garage, the typical width is 32 feet. 

2. What Is the Smallest Garage Door You Can Get?

Garage doors can be as small as 4 feet wide, often in the case of a small storage shed. Most shed doors, however, are at least 6 feet wide and about 7 feet tall. They are perfect for storing motorcycles and all-terrain vehicles (ATVs).

3. How Long Does It Take to Remove and Replace a Garage Door?

It can take about three to four hours to replace a garage door. However, it depends on the type and size of the garage door and the amount of work required. For example, installation is quicker and simpler if the new garage door is compatible with the available space and structure and your existing brackets and wiring are in good shape. Readjustments may take more time. 

Contact Us Today for Garage Door Measurements in Houston, TX

Measuring the garage door is only the first step. Next, you need to find the garage door that fits your space requirements and complements your home’s exterior. For most people, finding a trusted expert with a wide variety of quality garage doors that suits their taste is challenging.

Halo Overhead Doors is a full-service garage door company based in Houston with over 30 years of experience providing customers with the finest garage door solutions. Our trained professionals can help you find the correct dimensions and guide you in choosing from our large selection of door styles. Each of our installers has a minimum of five years of experience, so you get expert service every time.

Are you interested in fitting your home with new garage doors? Contact us today and take advantage of our personalized services. 

Contact Us Today