Getting the dimensions right for a double garage door matters more than most people think. The correct size affects vehicle clearance, insulation options, and the ease of installing an opener or storage inside the garage.
This article explains typical widths, heights, and the clearances to check before buying or making changes. The focus is on practical measurements and what each one means for everyday use.
Typical widths and heights to expect
Most homes use a handful of common widths and heights when it comes to double doors. These sizes reflect standard vehicle widths and common construction tolerances.
Knowing the typical ranges helps you choose a door that gives enough room for cars, mirrors, and frequent movement.
Common width ranges
Double doors usually fall in these width bands. Use these as a planning reference, not a definitive rule for every garage.
- 16 feet (192 inches): The most common double width in residential builds.
- 14 feet (168 inches): Often found in older or narrower two-car garages.
- 18 feet (216 inches): Used in wider custom garages or where extra clearance is desired.
Common height ranges
Height choices affect the kinds of vehicles and roof-mounted equipment you can store.
- 7 feet (84 inches): Standard height that fits most cars and small SUVs.
- 8 feet (96 inches): Popular for taller vehicles and easier passage for trucks.
- 9 to 10 feet: Selected for large trucks, vans, or when adding a loft or tall storage.
Key clearances: headroom, side room and backroom
Doors are about more than the opening size. You need to check the space above, beside, and behind the door opening to ensure proper fit and operation.
These clearances determine the type of track and operator that will work and whether modifications are required.
Headroom explained
Headroom is the space from the top of the opening to the ceiling or obstruction. Most sectional doors need at least 10 to 12 inches, while low-headroom tracks reduce that requirement to around 3.5 to 5 inches.
Measure headroom carefully if the garage has beams, ducts, or HVAC equipment above the door.
Side room and jamb width
Side room is the space from the door opening edge to the nearest wall or obstruction. Most manufacturers ask for 3 to 5 inches on each side to fit vertical tracks and weather seals.
Less side room may still work with special brackets, but it often increases costs and limits hardware choices.
Backroom and travel distance
Backroom is the clear depth inside the garage from the opening to the far wall. It needs to accommodate the door panels when open and the track system.
Standard recommendations start at about the door height plus 18 inches for a typical sectional door. For high lift or vertical lift systems, backroom needs increase significantly.
Measuring steps before buying
Accurate measurements cut down surprises during installation. Take three sets of measurements and note the smallest values.
Include width, height, and all clearances. Record any masonry, arches, or slope that could affect the opening.
How to measure width and height
Measure the inside of the jamb from left to right at three points: top, middle and bottom. Use the smallest measurement as the true width.
For height, measure from the floor to the underside of the header at three spots and use the shortest dimension. Irregularities can require custom doors or trim adjustments.
Check the floor and threshold
Uneven garage floors change how the door seals and can allow water entry. Measure floor slope and note any raised thresholds or drains.
A perfectly level threshold is rare, so allow a little tolerance when sizing the door and ordering seals.
Door types and their size implications
The style of door affects required clearances and the look of the opening. Two common residential types are sectional and roll-up, each with different needs.
Choosing the right type helps match available headroom, budget, and maintenance preferences.
Sectional doors
Sectional doors are built from horizontal panels that slide up and then back along ceiling tracks. They require more backroom but less height clearance when open.
They are easy to insulate and can be fitted with windows, making them ideal when energy efficiency matters.
Roll-up and tilt doors
Roll-up doors coil into a drum above the opening, which reduces headroom needs. Tilt-up designs pivot outward and then slide up.
Roll-up is a good option where headroom is tight, while tilt doors are simpler but need clear space in front to open safely.
Planning for vehicles, storage and future needs
Your vehicle mix and storage plans should influence the door size you choose. Aim for comfortable clearance rather than just enough space.
Think about mirror-to-mirror width, roof racks, and how often you’ll need to maneuver inside the garage.
Typical vehicle clearances
Most sedans are 6 to 6.5 feet wide including mirrors. SUVs and pickups often exceed 7 feet with mirrors folded, so extra width is important.
- Two small cars: 14 to 16 feet is usually enough.
- One large truck and a car: 16 to 18 feet gives easier access.
- Work trucks or vans: consider 18 feet or wider plus higher headroom.
Storage and workspace planning
If you plan racks, shelving, or a workbench, subtract that footprint from usable backroom. A door that’s wide but leaves no usable depth can still feel cramped.
Allow at least 2 to 3 feet of clearance behind parked vehicles for safe entry and small storage tasks.
Manufacturing tolerances and trim options
Doors come with tolerances to fit most openings, but large variations in the opening may need custom work. Trimming jambs or adding filler pieces is common.
Consider both functional and cosmetic options so the finished installation looks intentional and seals well.
Filling gaps and sealing
Weatherstripping and threshold seals handle small gaps, while larger mismatches may need a sill or custom jamb build-out. Proper sealing reduces drafts and pests.
Remember that an improperly sealed door increases heating and cooling costs and reduces comfort in climate-controlled garages.
Custom sizing when necessary
When the opening falls outside standard bands, manufacturers can produce custom panels. This raises cost but ensures a clean fit and operation.
Get multiple quotes if custom sizing is required, since costs vary by material and finish choices.
Conclusion
Choosing the right double door size starts with careful measurement and thinking about how the garage will be used. Typical widths run from 14 to 18 feet and heights from 7 to 9 feet, but variations and custom options exist.
Check headroom, side room and backroom before ordering. Plan for vehicles, storage, and any future changes to avoid costly adjustments later.
Frequently Asked Questions
What width is standard for a two-car opening?
Most two-car openings are 16 feet wide. This size allows two average cars to park side-by-side with reasonable mirror clearance. Fourteen and eighteen-foot openings are also common in older or custom spaces.
Can I use an 8-foot high door for a truck?
An 8-foot high door works for many pickup trucks and SUVs. Large vans or vehicles with roof racks might need 9 feet or more. Always measure vehicle height with accessories attached before deciding.
How much headroom do sectional doors need?
Standard sectional doors typically require 10 to 12 inches of headroom for the track and springs. Low-headroom options can reduce that need to around 3.5 to 5 inches at a higher cost.
What if my garage opening is not level?
Uneven openings can be handled by using the smallest measured width and height, then filling or trimming where needed. Significant irregularities sometimes mean a custom door or carpentry work to square the opening.
Are roll-up doors better for limited space?
Yes. Roll-up doors need less headroom because the curtain coils into a drum above the opening. They are a strong option when ceiling height is limited or where compact hardware is preferred.
