Before you install or replace a garage door, you need to determine the correct size. Common single doors are 8′, 9′ or 10′ wide, while double doors are usually 16′ or 18′ wide.
The door size is only a starting point. You also need to check the opening dimensions, available installation space and intended application. This guide explains common garage door sizes, how to measure the opening and when a custom size may be required.
What Is a Standard Garage Door Size?
A standard garage door size is a nominal width and height commonly used by manufacturers and building designers. Typical examples include 9′ × 7′ for a single door and 16′ × 7′ for a double door.
“Standard” does not mean that every manufacturer or market follows exactly the same dimensions. Available sizes can vary according to the panel system, local building practices and whether the project uses imperial or metric measurements.
If you are preparing a quotation or door schedule, standard sizes provide a useful reference. The final order still needs to match the finished opening, installation space and required door configuration.
Standard Garage Door Size Chart
The following dimensions are commonly used for residential garage doors in North America.
| Door Size | Approx. Metric Size | Type | Common Application |
| 8′ × 7′ | 2438 × 2134 mm | Single | Compact single-bay garage |
| 9′ × 7′ | 2743 × 2134 mm | Single | Standard residential garage |
| 9′ × 8′ | 2743 × 2438 mm | Single | Taller residential opening |
| 10′ × 7′ | 3048 × 2134 mm | Single | Wider single-bay garage |
| 10′ × 8′ | 3048 × 2438 mm | Single | SUV or pickup application |
| 16′ × 7′ | 4877 × 2134 mm | Double | Standard double-bay garage |
| 16′ × 8′ | 4877 × 2438 mm | Double | Taller double-bay garage |
| 18′ × 7′ | 5486 × 2134 mm | Double | Large residential garage |
| 18′ × 8′ | 5486 × 2438 mm | Double | Wide double-bay garage |
Metric dimensions are rounded conversions for reference. For production, especially on metric projects, the approved drawing and confirmed opening dimensions should control the order.
These are common industry sizes rather than a complete list of manufacturing possibilities. Panel construction, material, insulation, wind requirements and production capability can all affect the available range.
Common Single Garage Door Sizes
Common single garage door widths are 8′, 9′ and 10′. Standard heights are usually 7′ or 8′.
An 8-foot-wide door is generally used for compact openings, while 9′ × 7′ is a common size for standard single-bay projects. Where the building design allows more width, a 10-foot door provides a larger clear entrance.
A 7-foot height suits many standard openings. An 8-foot door is used when the project requires additional vertical clearance.
When you prepare a door schedule, confirm both the width and height for each opening rather than assuming that all single doors use the same dimensions.
Common Double Garage Door Sizes
Common double garage doors are usually 16′ or 18′ wide, with standard heights of 7′ or 8′.
A 16′ × 7′ door is a common starting point for double-bay residential projects. An 18-foot-wide door provides a wider continuous entrance where the building design allows it.
You can also choose between one double door and two independent single doors. A double door removes the center post, while two single doors allow each bay to operate separately. Confirm this arrangement before the structural openings are completed.
What Is the Difference Between Garage Door Size and Opening Size?
Garage door size refers to the nominal width and height of the door being ordered. Opening size refers to the clear width and height available in the building.
The two dimensions are closely related, but they describe different things. One identifies the product; the other describes the site where the product will be installed.
For example, a door may be quoted as 9′ × 7′, but the project drawing must still show whether the stated building dimension is a finished opening, rough opening or framing opening. These measurements should not be used interchangeably without checking the construction details.
Door Size
Door size is the nominal product size shown on the quotation, door schedule and order confirmation. It is used to determine the panel dimensions and the corresponding door system.
Finished Opening Size
The finished opening is the clear width and height after cladding, render, trim and other finishing materials have been installed. This is normally the most useful site dimension for installation review.
Rough and Framing Openings
A rough opening is measured before the final finishes are applied. A framing opening is formed by the structural jambs, columns and header.
After finishes are added, the clear finished opening may be smaller than either of these construction-stage measurements.
When you request a quotation, label each dimension clearly. For replacement work, measure the completed opening on site rather than relying only on the original building drawing. For projects with several doors, use the same dimensional reference throughout the quotation, shop drawings and door schedule.
How to Measure a Garage Door Opening
Before placing an order, measure both the finished opening and the available installation space.
- Opening width: Measure across the top, middle and bottom of the opening.
- Opening height: Measure on the left, center and right.
- Sideroom: Check the clear space on both sides for the tracks, brackets and hardware.
- Headroom: Measure from the top of the opening to the ceiling or lowest obstruction.
- Backroom: Measure the clear distance from the opening to the rear of the building.
- Obstructions: Record any beams, pipes, lights, ducts or sprinklers near the track area.
For an existing or irregular opening, record every measurement and check the diagonals to determine whether the opening is square. Do not rely only on the original building drawings.
Headroom and backroom affect the track arrangement rather than the nominal door size. Include site photographs or a section drawing if the ceiling structure or installation space is unusual.
How to Choose the Right Garage Door Size
Choosing the right garage door size starts with the way the building will be used. You need to consider the vehicle or equipment passing through the opening, the available approach space and whether a standard size can meet the project requirements.
Choose by Vehicle and Application
For passenger-vehicle projects, a 9-foot-wide single door is a common starting point. If the building will accommodate larger SUVs or pickup trucks, a 10-foot opening provides more clearance around the mirrors where the structural design permits it.
RV garages need to be checked separately. Use the complete vehicle height, including rooftop air-conditioning units, antennas and other fixed equipment. A general RV size chart may help with early planning, but it should not be used as the final specification.
The approach to the opening also matters. A pickup entering from a straight driveway may need less clearance than the same vehicle turning into the opening from a narrow yard.
For workshops and commercial buildings, consider the work taking place around the vehicle. Loading, forklift movement, maintenance operations and pedestrian access may require additional clearance beyond the vehicle dimensions.
Base the opening on the complete operating scenario rather than simply selecting the nearest standard catalogue size.
Decide Whether a Custom Size Is Needed
If a standard size suits the opening and application, it is usually the simplest choice. This is common in residential developments, repeat orders and projects designed around standard dimensions.
You may need a custom garage door when the project includes:
- An existing non-standard opening
- An RV or oversized vehicle
- A wide commercial opening
- Renovation or replacement work
- Metric architectural dimensions
- Restricted headroom
- High-lift or vertical-lift tracks
- Special wind-load requirements
- OEM or private-label specifications
- Several opening sizes within one project
For a project with several openings, prepare a door schedule showing the reference, size, quantity and configuration of each door. This allows dimensional differences to be resolved before production.
How Door Size Affects Springs, Tracks and Hardware
Two garage doors with the same appearance can require very different garage door hardware.
A large insulated door carries more weight than a smaller single-layer steel door. Adding windows or reinforcement changes the weight again.
For this reason, garage door springs should not be selected from door width and height alone. The final door weight and construction should determine the spring, cable, drum and shaft combination.
Panel reinforcement is another consideration. Wider panels have a greater span and may need additional struts or other reinforcement to control deflection.
Wind exposure also matters. A 16-foot-wide door presents a much larger surface to the wind than a small single door. In exposed locations, reinforcement and hardware should be reviewed together with the required wind load.
Operating frequency can change the specification as well. A door in a residential development and a similar-sized door in a busy workshop may look almost identical, but their spring-cycle and hardware requirements can be very different.
Final Thoughts
Standard garage door sizes are a useful starting point, but the final specification must match the finished opening, installation space and project requirements. For configuration support or a quotation, send your door sizes, quantities and project drawings to Gemax.
