You’re probably here because something’s changed. Maybe your partner wants their car tucked in at night. Maybe your tools and equipment have taken over every inch of space. Or maybe you’re just tired of parking in your exposed driveway and ready to build something that improves your everyday flow.

Whatever brought you here, one thing’s for sure: You need to figure out what garage size fits your needs and property. This guide breaks down our most popular 1-car garage sizes, how to make the most of your space, and what building options are worth getting for the long term. So let's dive into 3 most popular garage sizes.

Our Most Popular 1-Car Garage Sizes

When it comes to garage size, there’s really no one-size-fits-all. It depends on what you’re storing, how much walking room you want, and what your property layout allows. Below are three common 1-car metal garage sizes that work for different needs—and we’ll show you 3D examples with links so you can explore and customize from there.

(1) 18x25x9: Roomy, Reliable, and Ready for Anything

This is one of our better-selling sizes for a reason. It gives you enough width to comfortably park any vehicle, swing open the doors, and still walk around to the door. The 25-foot length gives you space to add shelves, tool rack, or hang up your bicycles. With width being perfect for a front facing overhead door and walk in door.

This is for you, if are:

• Sedan, SUV, or small truck owner

• Homeowner who wants room for both car and storage

• Adding a small workbench along the back wall

Check out this 18 x 25 3D garage render here to explore available options and different placements as a starting point.

(2) 12x30x8: Great for Narrow Lots and Extra Storage

This is a great option if you’ve got limited width on your property but decent depth. At 30 feet long, it gives you a full-length parking plus plenty of storage room at the front or even rear.

This is for you, if are:

• Located in area with narrow lots or alleys

• Storing tools, lawn equipment, or bikes alongside your vehicle

• Wanting to turn a portion of the space for a dedicated hobby shop.

Check out this 12 x 30 3D garage render here to explore available options and different placements as a starting point.

(3) 12x20x9: Just Enough Garage Without the Bulk

This is the most compact option, and it's great for those just looking to get their car out of the elements. No frills, nothing overbearing—just solid protection for your vehicle and room to walk out.

This is for you, if are:

• Needing basic vehicle protection

• Budget-conscious buyer

• Own a smaller homes with limited space

Check out this 12 x 20 3D garage render here to explore available options and different placements as a starting point.

Before You Start Settling on a 1-Car Garage Size, Walk Your Property

Before locking in dimensions, take a walk around your property. Roughly measure your available space and consider:

• Driveway access: Will you need to back up at an angle to leave? Any trees, fences, or slope to worry about?

• Walk in door access: Will you need your entry door on the side or front for ease?

• Overall usage: Are you an everyday commuter or hobbyist? The type of garage door matters especially if you have the options for overhead for ease or roll up door for infrequent use.

• Height: Taller garages (9 feet and up) allow more overhead storage and better airflow with gable vents, especially if the building sees direct sun most of the day.

Possible Setbacks Before You Build

You’ve walked your property and mapped out a few ideas—but before locking in your layout, it’s time to connect with your local city inspector. Every city handles site inspections differently, so don’t assume what works in one place will work in another.

If you’ve dealt with permits before, you probably know what to expect. But if this is your first time, here are a few common things that can slow your project down:

• Property Line: You can’t build right on the edge of your lot. Most zoning ordinances require your building to be set back anywhere from 5 to 15 feet from the property line. Check with your city or county for the exact number.

• Distance from Existing Structures: Just like with property lines, there are rules about how close you can build to another structure. These distances are often stricter in residential or suburban areas.

• Permits: Always plan on needing a permit—it’s safer and avoids costly delays. You’ll need to know your building size, type, and details before applying. If you’re ordering from UMB, we can provide certified engineering plans for an added cost to help make the process smoother.

• Foundation Requirements: A solid foundation saves time and issues during installation.

  • Concrete Slab: Should be 3" wider and longer than your building’s footprint—1.5" overhang on all sides—with a slight 0.25" slope for water runoff.

  • Gravel Pad: Needs to be 2' wider and longer on all sides to handle the building’s weight properly.

  • Dirt, Gravel, Asphalt Pad: Needs to be within 0-3” inches of level grade at all points. Anything beyond that will result in either a Leveling or Rescheduling Fee.

Why a Few Extra Feet for Your Garage Makes Life Easier

A few extra feet might not seem like much but ask anyone who’s had to sidestep around a car door or squeeze past a mower—it matters. That extra space makes your building easier to live with long term, so you’re not cussing up a storm when you stub something.

You’ll thank yourself when:

• You can add a nice metal shelving set and organize it with ease.

• You start a DIY project and don’t have to back out your vehicle.

• You upgrade to a full-size truck down the road and it still fits.

Want Help Figuring Out the Right Dimensions? Let’s Talk.

Now that you've read this guide, take 20 minutes to stroll your property and lay out some markers to get a rough idea. If you're still having troubles or need building advice, get in touch with us today through our online contact form, site chat, or call 309 278 8000.

Otherwise, start your quote today by giving us those rough measurements and pictures of the available space you have. Once you send it over, we’ll talk through your options and make something that works financially and effectively for your lifestyle.