Garage Bay Sizes: How to Size a Garage You Won't Outgrow

Almost nobody regrets building a garage too big. Plenty of people regret building one too small, and they figure it out the first time they try to open a truck door.

Sizing is the cheapest decision on the whole job and the one people rush. Here is how we handle it as garage builders, and what it costs once you have picked, for a garage in Augusta.

Garage bay sizes come down to two numbers: how wide each bay is, and how deep the building is. Width gets all the attention. Depth is what people get wrong.

Here is how to size it properly.

Standard garage bay sizes by width

Garages run in roughly 12-foot increments per bay. That is the working standard.

You can go narrower. It gets tight fast, and tight is where door dings live.

You can also go wider, in 14-foot or 16-foot increments. When people do, it is almost always for the same reason: workspace. A mechanic's bay, a wood shop, a bench along one wall. If you want to work in the building and not just park in it, buy the extra width per bay rather than an extra bay.

Depth is the number people get wrong

This is where I see the most regret, so let me put real vehicle lengths against it. What actually fits in a two-car garage goes deeper on the vehicle side.

Now read that against the common depths.

20 feet fits a small car with room to walk around it. It does not fit a modern crew-cab pickup at all. An F-150 SuperCrew with a 6.5-foot bed is 20.3 feet long. It physically will not close the door behind it in a 20-foot building.

24 feet is the real minimum for a truck or a full-size SUV. It works, but it is snug. One independent builder measured a full-size truck in a 24-foot garage and found 12 inches at the front and 4 inches at the back.

28 feet is where a truck fits and you can still walk around it, get to a workbench, and store the things a Maine garage ends up storing.

Our standing recommendation:

The plow problem

If you plow, the vehicle table above is not your number.

A truck with a plow hung on the front is meaningfully longer than the same truck bare, and here is the frustrating part: no plow manufacturer publishes the forward projection. Fisher, Boss and Western all publish blade width and blade height. None of them publish how far the mount and blade stick out past the bumper.

What exists is owner experience, and it is consistent. Reports of an extended-cab short-bed truck with a plow and a spreader clearing a 24-foot building by about two inches. An F-350 with a plow in a 26x26 leaving roughly a foot up front. People who actually store a plow rig indoors through a Maine winter tend to build 30 to 32 feet deep.

So do not take a number off the internet, including mine. Hang the plow, park the truck, and measure bumper-of-plow to tailgate with a tape. Then add three feet so you can walk around it. That measurement is the only one that matters, and it takes ten minutes.

Wall height and door height

Ten-foot walls are the standard, and there is a reason.

The common way we build it is a two-foot curb around the outside perimeter of the walls (sometimes one foot) with nine-foot studs on top. Either way you land near ten feet of wall.

That gets you a nine-foot-tall door, which clears essentially every residential vehicle, including a truck with a rack, a roof box, or a plow frame.

Nine feet is the height we recommend by default. The cost difference is small and the regret for going short is permanent.

If you want a car lift, that is a different conversation and taller walls are required. Tell us at the estimate and we will size the walls for it, because it is not something you can add later without rebuilding.

Snow load and wide spans in Maine

The wider you span, the more the roof structure matters, and Maine roofs carry real weight.

Maine has no single statewide snow load. Designers pull the ground snow load per address, and in the counties where the tool requires a case study the guidance sets a floor of not less than 100 pounds per square foot. Towns publish their own numbers too, and the town's number governs. Bangor publishes 70 psf. Bar Harbor publishes 60.

Practically, this means the truss package on a 36-foot three-bay is not a scaled-up version of the one on a 24-foot two-bay. It is engineered for your address. Get the design snow load from your code enforcement officer before anyone prices a roof.

Design it so you can add on later

If there is any chance you will want more building, say so before the foundation is laid. The garage building cost guide shows what each extra bay actually adds, and the Kennebec County guide covers pricing outside Augusta.

Expanding off a gable end is straightforward if the building was planned for it. Expanding off a side wall usually is not, because you are cutting into the roof structure.

The things that keep the door open:

• Put the expandable end where the lot allows growth, and check your setbacks in that direction now
• Keep utilities and the electrical panel out of the wall you might remove
• Plan the roof so a future addition can run under the same ridge

None of that costs meaningful money at design time. All of it costs real money to retrofit.

Boats, campers and trailers

Common in Maine and worth sizing for honestly.

A boat on a trailer is usually longer than the boat. Add the tongue, and add clearance to swing it. Campers and travel trailers frequently need a 12-foot-wide door rather than a 9-foot, and often 12 or more feet of height, which pushes you out of standard garage construction into something closer to a barn.

If a trailer is in the plan, measure it on the trailer, with the tongue, and bring that number to the design conversation. It changes the building.

Quick sizing guide

Frequently asked questions

How wide is a standard garage bay? About 12 feet. A one-bay is typically 12 feet wide, a two-bay 24, a three-bay 36. Going to 14 or 16 feet per bay is common when you want working space beside the vehicle rather than just parking.

How deep should a garage be for a pickup truck? Twenty-four feet is the practical minimum, and it is tight. Modern crew-cab pickups run 19 to 22 feet long on their own. Twenty-eight feet gives you the truck plus room to walk around it and store things.

Will a truck fit in a 20-foot garage? Generally no. An F-150 SuperCrew with a 6.5-foot bed is 20.3 feet long, which is longer than the building is deep. Twenty-foot depth is a car garage.

How much deeper does a garage need to be for a plow? No plow manufacturer publishes forward projection, so there is no reliable published number. Owners who store plow rigs indoors commonly build 30 to 32 feet. Measure your own truck with the plow mounted and add walking room.

What ceiling height do I need for a garage? Ten-foot walls are standard and allow a nine-foot door, which clears all residential vehicles. Lifts and lofts need more.

Can I add onto a garage later? Yes, if it was planned for. Gable-end expansion is much simpler than cutting into a side wall. Decide the likely direction before the foundation goes in, and confirm your setbacks allow growth that way.

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Dimensions and figures on this page are general guidance for Maine homeowners, not a quote and not a code ruling. Snow loads, setbacks and permit requirements vary by municipality. Your code enforcement officer has the final say.