Figuring out the average size of garage door before you start a renovation saves you a massive headache later on. It's one of those things most homeowners don't think about until they're trying to park a brand-new, oversized SUV into a garage built in the 1970s. Suddenly, those few inches of clearance become the most important measurements in your life. While there's no "one size fits all" for every single house, the industry definitely has some standard go-to numbers that cover about 90% of what you'll see on the market.
The Standard Single Garage Door
If you have a one-car garage, you're likely looking at a few specific dimensions. For a long time, the most common average size of garage door for a single bay was 8 feet wide by 7 feet tall. You'll still see this in plenty of older suburban neighborhoods. It's enough to get a sedan or a compact crossover inside without too much stress, but it doesn't leave a whole lot of breathing room on the sides.
Lately, though, builders have been leaning more toward 9 feet wide by 7 feet tall as the new "standard." That extra foot might not sound like a lot on paper, but when you're backing out in a rush on a rainy Monday morning, you'll be glad it's there. It gives you that extra margin of error so you don't accidentally clip your side-view mirror on the door frame. If you're building from scratch or reframing an old opening, aiming for at least 9 feet wide is a smart move for future-proofing your home.
Stepping Up to Double Doors
For homes with a two-car garage, you usually have two choices: two single doors or one giant double door. If you go with the single large door, the most common average size of garage door is 16 feet wide by 7 feet tall. This is the big kahuna of the garage world. It's designed to fit two standard vehicles side-by-side, though it can get a bit tight if you're trying to squeeze two full-sized trucks in there.
Some people prefer a slightly wider 18-foot door if they have the space. This is a lifesaver if your driveway has a bit of an awkward angle or if you use the sides of your garage for storage, like housing lawnmowers, bikes, or workbenches. Having that extra width means you aren't constantly worried about dings and scratches every time someone opens a car door inside the garage.
Don't Forget About the Height
We talk a lot about width, but height is where a lot of people run into trouble. The standard height is almost always 7 feet. For most cars, this is perfectly fine. However, if you've got a lifted truck, a large van, or if you like to keep a cargo carrier or a roof rack on top of your SUV, 7 feet can feel incredibly low.
In many modern builds, it's becoming more common to see 8-foot-tall doors. If you have the headroom in your garage ceiling, upgrading to an 8-foot door is one of those small changes that significantly increases the utility (and resale value) of your home. It's much better to have that extra foot and not need it than to realize your new truck won't fit by a measly two inches.
Why These Sizes Actually Exist
You might wonder why we've settled on these specific numbers. It mostly comes down to how cars are built and how much weight a standard garage door opener can handle easily. Garage door manufacturers make these "stock" sizes because they are cost-effective to produce and fit the vast majority of residential framing.
When you stick to an average size of garage door, you're also saving yourself a chunk of change. Custom-sized doors require special ordering, longer wait times, and often a much higher price tag. If your opening is even an inch or two off the standard, a professional installer can sometimes "trim out" the opening to make a standard door fit, which is usually way cheaper than ordering a bespoke door from the factory.
Measuring Your Space Correctly
Before you go out and buy a door based on what you think you have, you've got to pull out the tape measure. Measuring for a garage door isn't just about the hole in the wall. You have to look at the "guts" of the garage too.
First, measure the width and height of the finished opening. This is your primary measurement. But then, you need to check the "sideroom"—the space on the left and right of the opening where the vertical tracks will sit. Usually, you need about 4 inches on each side.
Then there's the "headroom," which is the space between the top of the door opening and the ceiling. This is where the springs and the horizontal tracks live. If you don't have enough headroom (usually about 10 to 12 inches), you might need a special "low-headroom" kit, or you might not be able to fit a standard door at all. Finally, check the "backroom"—the distance from the opening to the back of the garage. The door has to have somewhere to go when it's open, after all!
Thinking About Custom and RV Sizes
Not everyone is driving a Honda Civic. If you're a hobbyist or an adventurer, the average size of garage door might not cut it for you. RV doors, for instance, are a completely different beast. These usually start at 10 to 12 feet wide and can go up to 14 or 16 feet in height.
Even for regular homes, some people opt for golf cart doors. These are cute little things, usually around 5 or 6 feet wide. They're great if you have a side-entry garage or a detached shed where you keep smaller equipment. While they aren't the standard "car" size, they follow similar manufacturing rules.
Does the Material Change the Size?
The material you choose—whether it's steel, wood, aluminum, or fiberglass—doesn't usually change the standard sizes available, but it does change the weight. A 16x7 wooden door is incredibly heavy compared to a 16x7 uninsulated steel door. This matters because the bigger the door, the more robust your spring system and opener need to be.
If you're going for a very large or non-standard size, steel is often the go-to because it's lighter and easier to reinforce. Wood is beautiful, but on a massive double-wide door, it can become a structural challenge that requires heavy-duty hardware that might not fit in a standard residential setup.
Making the Final Decision
At the end of the day, the average size of garage door is there to make your life easier. Most homes are built to accommodate these standard dimensions because it makes replacement and repair simple. If you're looking at a house and the garage door looks a bit "off," it's worth measuring it before you commit to buying.
If you're currently stuck with a door that's a bit too small, don't lose hope. Depending on how your house is framed, a contractor can often enlarge the opening to move you up from an 8-foot door to a 9-foot door. It's a bit of work, sure, but it beats scraping your fenders every time you park. Just remember to measure twice, think about what you'll be driving five years from now, and choose the size that gives you the most peace of mind.