What are the standard garage door sizes for a house?

Standard residential garage doors come in a small set of widths and two common heights. Single-car doors are 8, 9, or 10 feet wide. Double-car doors are 16 or 18 feet wide. Both are usually 7 or 8 feet tall. The two most common sizes in American homes are 9 feet by 7 feet for a single door and 16 feet by 7 feet for a two-car door. Anything outside these is custom, including taller RV and workshop doors.

Common single and double door sizes

Most garage doors are sized in 1-foot or 2-foot steps, so manufacturers can stock common dimensions and still cover most homes. For a single-car opening, the standard widths are 8, 9, and 10 feet. The 9-foot width is the most popular because it gives comfortable room to pull a car in and out without clipping a mirror.

For a two-car garage, you have a choice of layout. A single wide double door is typically 16 feet wide, with 18 feet common on newer or larger builds. Some two-car garages instead use two separate single doors, each 8 or 9 feet wide, with a post between them.

Heights are simpler. 7 feet is the long-time standard and fits most cars, SUVs, and light trucks. 8 feet is increasingly common on new homes and is the right call if you own a tall truck, a van, a lifted vehicle, or a roof rack. A 6-foot-6 height also exists on some older homes, but it is tight for modern vehicles and usually gets replaced with a taller door when the opening allows. Below is the quick reference:

Door type	Standard widths	Standard heights
Single-car	8, 9, 10 ft	7 or 8 ft
Double-car	16, 18 ft	7 or 8 ft
RV / oversized	12 to 20 ft	8 to 14 ft

When you need a non-standard size

Standard sizes cover most houses, but several situations call for custom. RV and boat garages need extra height, often 10 to 14 feet, plus added width, so the door is almost always a special order. Workshops and detached shops sometimes use 12-foot widths to fit trailers or equipment.

Older homes are the other common exception. Houses built decades ago may have openings that do not match today's even-foot sizes, because building methods were less standardized. A 1920s detached garage might have an 8-foot-6 opening that needs a custom door or a reframed opening. Carriage-style and historic homes also sometimes use swing-out or narrower doors that do not follow modern charts.

If your opening is an odd size, you have two paths: order a custom-built door to fit the exact opening, or have a contractor reframe the rough opening to a standard size so you can use a stock door. Reframing can be cheaper than a custom door if the wall allows it, but it depends on the header and the structure around the opening.

Rough opening and clearance you need

The door size is the finished opening, the daylight space you drive through. The rough opening framed in the wall should match the nominal door size closely, so a 9-by-7 door needs a roughly 9-foot by 7-foot finished opening. Around that opening, the door needs space to work, and this is where many garages run short.

You need clearance in three directions. Side room, the space from the edge of the opening to the side wall, is typically about 3.75 inches on each side for standard hardware. Headroom, the space above the opening up to the ceiling, is usually 10 to 12 inches for a standard torsion spring setup, and more for some systems. Backroom, the depth into the garage, generally needs to equal the door height plus about 18 inches so the open door has room to sit along the ceiling.

When headroom is tight, a low-headroom track kit can fit a door into as little as a few inches of overhead space, and a high-lift conversion can do the opposite for tall garages. A measurement check before ordering avoids the costly surprise of a door that physically cannot open in the space you have.

How size affects price, weight, and your opener

Door size does more than decide whether your car fits. It drives the price, the weight, and the hardware behind the door. A wider door uses more material, so a 16-foot double costs more than a 9-foot single in the same style and insulation level. Going from a 7-foot to an 8-foot height adds an extra panel course, which adds cost and weight as well.

Weight matters because the springs do the lifting, not the opener. A bigger, heavier door needs larger or higher-rated torsion springs to stay balanced, and those springs must be matched to the door's actual weight. This is why size and material go together: a 16-foot insulated steel door weighs far more than an 8-foot single-layer door, and its spring system is sized accordingly.

Your opener has to suit the door too. Most standard residential openers handle 7- and 8-foot-tall doors up to common widths, but a very large, heavy, or tall door may call for a higher-horsepower or wall-mounted opener. Picking the door size first, then sizing the springs and opener to it, is the order that keeps the whole system smooth and reliable. Guessing on size and forcing undersized hardware to fit is what leads to early wear and noisy operation.

How to confirm the right size for your garage

Start by measuring the opening itself: width and height of the finished hole at its widest and tallest points. Then measure side room on both sides, headroom above the opening, and backroom depth into the garage. Write down all five numbers before you shop, because they decide both the door size and the hardware that will fit.

Measure at more than one point, since openings are not always perfectly square on older homes. If your numbers match a standard size and you have the clearances, you can order a stock door. If anything is non-standard, an odd opening or tight headroom, that points to a custom door or a special track kit rather than a problem you can ignore. Getting this right up front is what keeps an installation smooth.

One common mistake is ordering by the size of the old door instead of the opening. The previous door may have been the wrong size, or trimmed to fit, so measure the actual framed opening rather than assuming the existing door is correct. Another is forgetting the height of vehicles you plan to buy later. If a tall truck or van is in your future, choosing an 8-foot height now is far cheaper than reframing the opening for taller clearance down the road.

A professional measure is free and removes the guesswork, especially on older Denver-area homes where openings often do not match modern charts. G Brothers will measure your opening, check all clearances, and confirm whether a standard or custom door fits before anything is ordered.