What Are the Standard Dimensions for a One-Car Garage?

Planning a garage build or upgrade and worried about fitting your car and storage? I will clarify the standard sizes so you can avoid costly mistakes.

We will cover the minimum and comfortable width, practical depth ranges, how to calculate square footage, and adjustments for trucks or extra gear.

My work as a residential garage technician involves daily measurements and layouts, giving you shop-tested guidance.

Ease of Installation & Time Estimate

Planning your garage layout is one of the easier projects you can take on. On a scale of one to ten, I rate it a three in difficulty. Creating garage design planning drawings can help you map out storage, doorways, and utilities before you begin. These drawings set the stage for precise measurements and smooth project execution.

The active work is just measuring, thinking, and sketching. You can do it all with a 25-foot measuring tape, a notepad, and some graph paper. I like the Stanley Powerlock tape for this; it’s sturdy and the lock mechanism is reliable. The whole process takes a focused 2 to 4 hours.

This is a perfect solo job you can knock out on a Saturday morning before moving on to the rest of your day.

The Pro’s Numbers: Standard One-Car Garage Dimensions

Let’s answer the big question right away. What are the standard dimensions for a one-car garage?

The industry-standard range you’ll hear from most builders is 12 feet wide by 20 feet deep. That’s the classic starting point.

Think of that 12′ x 20′ figure as a foundation, not your final answer. It gets a sedan inside, but it often doesn’t leave room for anything else. Your specific car, your storage needs, and your local rules will shape the final plan.

Before you sketch anything, check your local building codes. Your city or county will have minimum requirements, and sometimes homeowner association rules are even stricter. Starting with code keeps your project safe and legal from day one.

Width: More Than Just Fitting the Car

What is the standard width for a one-car garage? A 12-foot width is the practical, bare-minimum standard.

Here’s my rule of thumb: if your garage door is 9 feet wide (a common size—check out the standard dimensions), you need at least 3 extra feet of interior width. This gives you about 18 inches of space on each side of the car. It’s like fitting through a doorway without turning sideways. You can do it, but it’s a tight squeeze.

In a 12-foot wide space, you risk door dings on your walls and you’ll have to carefully slide out of your car. I’ve seen too many homeowners frustrated by this. For comfort, I advise going to 14 feet wide if your lot allows it. This gives you room to open a door fully and step out easily.

Depth: The Make-or-Break Measurement

For depth, 20 feet is the typical target. This works for most midsize sedans and SUVs.

You have to think about the garage door itself. If you build a 20-foot deep garage and park a car that’s 17 feet long, you only have 3 feet in front of the bumper. That space gets eaten up by the door’s travel path and the thickness of the wall. Go any shorter, and your car’s bumper might actually sit in the doorway.

If you want any functional space in front of your car for a workbench, storage rack, or freezer, plan for 22 to 24 feet of depth. That extra 2 to 4 feet makes the garage a usable room, not just a parking spot, which is something you should consider when looking into garage length and depth.

Turning Dimensions into Square Footage

So, what is the standard square footage for a one-car garage? The math is simple.

Take our standard starting point: 12 feet wide multiplied by 20 feet deep equals 240 square feet.

Changing your depth is the easiest way to gain functional space. If you go with a more comfortable 12-foot by 24-foot plan, you get 288 square feet. That’s an extra 48 square feet for your tools and gear, just by adding 4 feet to the length.

How Your Specific Car Changes the Math

Standard dimensions are a great starting point, but you must measure your specific vehicle. I learned this lesson on my first garage build. I planned around a neighbor’s mid-size sedan, only to find my own truck wouldn’t fit with the shelving I had planned. It was a frustrating and avoidable mistake.

Do not assume your car matches online specs; grab a tape measure and check for yourself. Vehicle shapes, mirror placement, and even open door arcs vary wildly between models. Your real-world measurement is the only number that matters for planning.

The Right Tool for an Accurate Job

A 25-foot tape measure works, but for speed and solo accuracy, I now use a Bosch GLM 20 laser distance measure. It’s a small, pistol-grip tool that gives me a perfect measurement in seconds. I can stand at my bumper, point it at the wall, and get the exact length. It eliminates the hassle of holding a tape straight and wrestling with it when I’m by myself. For a homeowner planning a major project, it’s a worthwhile investment over a basic tape.

Vehicle Size Comparison

To give you a realistic idea of what you’re working with, here are the average dimensions for common vehicle types parked in my clients’ garages. Remember, these are averages-your make and model could be different.

• Compact Sedan (e.g., Honda Civic): Roughly 6 feet wide by 15 feet long.
• Full-Size SUV (e.g., Chevrolet Tahoe): Closer to 7 feet wide by 18 feet long.
• Full-Size Truck (e.g., Ford F-150): Often over 7.5 feet wide (mirrors folded) and 20 feet long.

Modern trucks and SUVs are the main reason “standard” garage sizes often feel too tight. They’ve grown significantly over the past 20 years, while many garage footprints have not.

The Non-Negiable Clearance Rule

Once you have your vehicle’s width, you must add space on both sides. My rule, born from experience, is a minimum of 3 feet of clear floor space on each side of the car.

This isn’t just a nice-to-have. This clearance is for:

• Opening your car doors fully without dinging the wall or your other vehicle.
• Having room to walk comfortably between the car and your workbench or storage.
• Getting a floor jack or wheel dolly in place for maintenance.
• Allowing for wall-mounted cabinets or shelving that protrude a few inches.

Think of it this way: if your car is 7 feet wide, your garage’s interior clear width should be at least 13 feet (7 ft + 3 ft + 3 ft). That 3-foot buffer is what transforms a parking closet into a functional garage workshop.

Ceiling Height: Your Secret Weapon for Storage

When planning a garage, people fixate on width and depth. They forget to look up. The ceiling is your most powerful storage real estate, and its height decides everything.

The common minimum you’ll find is 8 feet. This works for parking a sedan, but that’s it. Once you add openers, light fixtures, or even a roof rack, you’re brushing the ceiling. I’ve installed hundreds of storage racks, and an 8-foot ceiling leaves you almost no overhead space. It feels cramped the moment you try to do more than just park.

If you are building new or finishing a space, I strongly recommend pushing for a 9-foot or 10-foot ceiling. That extra 12 to 24 inches is transformative. It lets you install sturdy overhead storage racks for seasonal items, luggage, or bins. I prefer the Proslat Overhead Rack system for these jobs because its steel construction and clear weight ratings (often 600 lbs per bay) let homeowners load it with confidence.

The biggest game-changer, though, is for car care. A 10-foot ceiling is the gateway to using a portable hydraulic lift, like a QuickJack. You need that clear overhead space to safely raise a vehicle for oil changes, tire rotations, or detailing. Trying to work under a car on jack stands in a low garage is a back-breaking safety hazard.

This height difference is what separates a basic attached garage from a true detached workshop. An attached garage is often built to the same roof line as the house, limiting your options. A custom detached structure gives you control. In my own detached shop, I went with a 10-foot ceiling. I can store my canoe overhead and have ample room for a future two-post lift. That flexibility is worth the initial planning.

Comparing Garage Sizes: From One-Car to Four-Car

Homeowners often ask about larger garage sizes when they’re planning a storage system, a workshop, or just need to know how much lawn equipment will fit. Let’s put the common sizes side by side so you can visualize the space you’re working with.

A two-car garage isn’t simply double a one-car. The shared wall and the space needed for two large doors to operate eats into the middle. I always recommend clients treat a standard two-car (20×20) as a place for two midsize sedans, not two full-size trucks with room to walk around. That’s where two-truck garage dimensions come into play. When two trucks are the goal, you’ll usually need more length and width than a 20×20 bay.

Now, that 1 1/2 car garage needs special attention because its purpose is often misunderstood. It’s not just a slightly bigger one-car garage. Builders design it as a smart compromise. You get a full vehicle stall plus a dedicated zone for deep storage or a compact workspace.

I’ve helped dozens of homeowners use that extra four feet of width effectively. Here’s what fits in that flex zone:

• A 24-inch deep workbench from Husky or Craftsman, with a vise and pegboard above it.
• Tall, freestanding shelving units for plastic storage totes.
• A dedicated area for recycling bins and bulky yard waste bags.
• Wall-mounted racks for bicycles, freeing up the entire floor.

If you’re parking a car in a 1.5-car garage, that flex zone is where you should plan your main storage wall. It keeps items off the floor and makes the most of the vertical space without door interference.

Planning Your Layout: A Pro’s Walkthrough

Knowing the dimensions on paper is one thing. Using every inch effectively is another. I tell homeowners to think of their garage floor like a grid and divide it into three clear zones: the vehicle zone, the tool zone, and the storage zone.

• The Vehicle Zone: This is the primary space your car occupies. Mark it out with painter’s tape.
• The Tool Zone: This is for your workbench, primary tool chest, and the tools you use most often.
• The Storage Zone: This is for seasonal items, bins, and anything you need to keep but don’t use weekly.

The single biggest mistake I see is people parking their car and then filling every last inch around it, leaving no room to move. You must leave a safe walkway. I recommend at least 3 feet of clear space along the driver’s side door and at the front or rear bumper. This lets you open the door fully, walk around the car with groceries, and check tire pressure without squeezing against a wall.

Now, think about doors, not just car doors. If you’re placing a storage cabinet or a workbench, you need to account for its door and drawer swing. A cabinet with two doors that swing open 90 degrees needs that space clear in front of it. I learned this the hard way years ago when I mounted a Gladiator cabinet and couldn’t open the right door fully because of my trash bins.

The Garage Door: Sizing the Opening Correctly

Here’s a detail that surprises many folks: the garage itself and the garage door are not the same width. Your 12-foot-wide garage will have a door opening that is narrower. Standard widths for garage doors range from 8 to 10 feet for single doors, with variations for double and RV-sized openings. Whether you’re looking at a single or double door, or an RV-sized opening, these dimensions matter for fit and function.

My rule of thumb is to choose a garage door that is 2 to 3 feet wider than the widest point of your car, which is almost always the side mirrors. For a typical sedan with mirrors that span about 6.5 feet, an 8-foot door is the bare minimum. I find it tight. A 9-foot door is my go-to recommendation for most modern cars and small SUVs-it gives you that crucial extra few inches on each side for a stress-free pull-in, especially in the rain or dark.

If you drive a full-size truck or SUV, you should be looking at a 10-foot door. I installed a 10-foot Clopay door on my own garage last year to fit my pickup, and the extra width makes a noticeable difference in daily use. You’re not just buying a door for the car you have today, but for the one you might own in 10 years.

When NOT to Rely on Standard Dimensions

Using a 12′ x 22′ plan as a starting point is smart, but treating it as a final blueprint is a mistake. I’ve seen too many homeowners get burned by just copying their neighbor’s garage.

Your specific vehicle, property lines, and the land itself can make those standard numbers completely useless.

The “Standard” Garage is Too Small for Many Vehicles

Think of a standard one-car garage as a size “medium” t-shirt. It fits a basic sedan okay, but try to put a broad-shouldered linebacker in it, and you’ve got a problem.

• Full-Size Trucks & SUVs: A modern crew-cab F-150 is often over 19 feet long and nearly 7 feet wide. In a 12′ wide space, you’ll have less than 30 inches of space on each side. Good luck opening your door without hitting the wall, your toolbox, or the freezer.
• Dually Trucks: These workhorses can be over 8 feet wide. They simply will not fit between two standard 4-inch wall studs. You need a custom, wider door and a much wider interior.
• Classic Cars & Project Vehicles: My ’72 Chevelle project taught me this lesson. You need extra room to walk around it, open the hood fully, and have space for a workbench and tools. A minimum of 16′ x 24′ gave me the workspace I needed without feeling claustrophobic.

Measure your actual vehicle’s width with the mirrors extended and add at least 3 feet of total width for basic clearance before you even think about storage.

Your Property Lines Will Dictate the Maximum Size

This is where I tell every client to stop planning and go visit their local building department. Zoning setbacks are non-negotiable.

Your city or county code says your garage must be, for example, 5 feet from the side property line and 20 feet from the rear. If your lot is narrow, those rules might shrink your buildable area down to a 14-foot wide strip. Suddenly, a 12-foot wide garage won’t fit with proper wall construction. You have to design from your property lines inward, not the other way around.

Slope and Drainage Are Foundation Killers

I helped a friend build on a lot with a mild slope. We thought we could just pour a slightly thicker slab. We were wrong.

If your building site has more than a few inches of slope across the garage footprint, you need a professional site plan.

A significant slope requires engineered fill, a stepped foundation, or a retaining wall. Getting this wrong leads to cracked slabs, water pouring under your door, and doors that never sit square. For any noticeable slope, hire a contractor early. The cost for their site evaluation is cheap insurance against a failing garage floor.

My Top Tool for Visualizing Your Space

Before you spend a dime on cabinets or racks, take your plan for a test drive. I use the free Gladiator GarageWorks online planner because it’s straightforward and doesn’t require an account to start. It’s the digital equivalent of sketching on graph paper, but with realistic 3D models you can spin around.

Here’s how I use it for every client consultation:

1. First, I grab my laser measure-a Bosch GLM 20-and get the exact width, depth, and height of the garage. I note the locations of doors, windows, and electrical outlets.
2. In the planner, I input those precise numbers to build the virtual shell of the space.
3. Then, I start dragging in virtual storage. I test if a 36-inch wide cabinet leaves enough room to open a car door. I see if a workbench along the back wall still allows the overhead door to close.

This simple digital rehearsal takes maybe twenty minutes but it prevents the all-too-common and expensive mistake of ordering a storage system that simply doesn’t fit your unique space.

Log Entry: The “Dead Zone” Above the Garage Door

One of my favorite storage secrets is reclaiming the empty air above where the garage door rests when open. Most people look at that area and see nothing. I see free real estate for bulky, lightweight items you only need once a year. It’s a smart trick, especially when you’re maximizing small garage storage.

In my own garage, I installed shallow, wall-mounted shelves up there for holiday decorations and empty coolers. The key is using brackets designed for vertical slatwall or sturdy, low-profile shelving like the Rubbermaid FastTrack system. You need to keep everything very shallow, no more than 12 inches deep.

The safety rule here is non-negotiable. Before you drill a single hole:

• Raise your garage door completely.
• Use a tape measure to confirm there is a minimum 6-inch gap between the highest point of the door’s travel path and where your shelf will be.
• Always secure your shelf brackets directly into the wall studs using a stud finder; drywall anchors are not sufficient for overhead storage.

This spot is perfect for items made of plastic or fabric, but avoid storing anything heavy or metal up there. You don’t want a toolbox falling onto your car or the garage door itself.

Maintaining Your Efficient Garage Space

Getting the right width and depth for your one-car garage is just the start. Those good dimensions make daily upkeep much simpler. A well-planned space is easier to clean, organize, and keep safe. Think of it like a kitchen. A kitchen with good counter space and cabinet layout is a joy to use. Your garage works the same way.

Seal Your Concrete to Cut Down on Dust and Stains

Your new concrete floor needs protection. Without it, the surface will constantly shed fine dust and soak up oil leaks like a sponge. I seal every floor I work on. My go-to product is GhostShield Silicate Densifier. It’s not a topical coating that can peel. Instead, it soaks into the concrete and chemically reacts to harden it from within.

Applying a silicate densifier like GhostShield is a one-time job that permanently reduces dust and makes wiping up spills easy. I find it more reliable than epoxy or paint in a busy garage where you’re dragging tools and parking a car. Here’s my process:

1. Thoroughly clean the floor. For a new slab, a simple acid etch or mechanical grind opens the pores.
2. Apply the GhostShield with a garden sprayer. It’s thin and watery, so it soaks right in.
3. Let it cure. That’s it. You’ll notice a harder, less dusty surface in a few days.

Get Everything Up on the Walls

Floor space is your most valuable asset. The moment you start putting toolboxes, bikes, or bins on the floor, you lose your clean walking path. The solution is vertical storage. I recommend one of two systems: slatwall panels or tempered pegboard. Both are winners, but for different reasons.

I’ve installed a lot of slatwall, like the kind from DIYHomeCenter or similar generic brands. If you mount slatwall panels directly to the wall studs, you can confidently hang 75 pounds per panel. That’s enough for a heavy duty shelf, multiple power tools, or a ladder. The hooks slide in and are easy to rearrange.

Tempered pegboard from a store like Home Depot is my other favorite. It’s cheaper and perfect for lighter hand tools, extension cords, and gardening supplies. Use 1×2 furring strips behind it to create an air gap. This lets the hooks lock in securely from the back. Never mount pegboard flat against the wall; the hooks will constantly pop out.

Commit to a Seasonal Declutter Cycle

Even the best system gets messy. Life happens. A seasonal reset keeps your efficient layout working for you. I do this every spring and fall in my own garage. It takes an afternoon and makes the space feel new again.

• Pull everything out from the walls and sweep thoroughly.
• As you put items back, ask: Have I used this in the last year? Does it have a designated spot?
• Be ruthless with broken items, empty paint cans, and leftover project scraps. Check your local waste guidelines for proper disposal of chemicals and old gas.

A quick seasonal review stops clutter from reclaiming the floor space you carefully planned for your car and projects. It’s the simplest habit to maintain the garage you’ve invested in.

FAQ: The Garage Care Pro’s Straight Talk on One-Car Garage Size

Is a 12-foot wide garage really wide enough?

It is the bare minimum, but I don’t recommend it for daily use. You’ll have less than 30 inches on each side of your car, making door dings and tight squeezes inevitable. For a functional space, aim for 14 feet to allow for comfortable door opening and basic wall storage.

My garage is the standard 240 sq ft. How do I make it feel larger?

You maximize vertical space. Install sturdy overhead racks and floor-to-ceiling slatwall to get all storage off the floor. Keeping the entire footprint clear for your vehicle and movement is the single biggest trick to making a standard-sized garage feel spacious and workable.

I already have a “standard” one-car garage that feels too tight. What can I do?

First, conduct a clearance audit. Measure the space between your car’s doors and the walls/objects beside them. If you have less than 24 inches, your immediate fix is to relocate all storage to the front or rear wall using vertical systems. This reclaims your critical side clearance.

Is the garage door width or the interior width more important?

Both are critical, but the door is the bottleneck. Your interior can be 14 feet wide, but an 8-foot door makes parking a modern SUV a stressful event. My rule: your garage door should be at least 2 feet wider than your vehicle’s mirrors. For most, this means upgrading to a 9-foot or 10-foot door. Sometimes you may need to modify the door’s width or height to fit your garage and vehicle. This is where a width-and-height modification becomes a practical option.

Wrapping Up Your One-Car Garage Plan

Remember, the best garage dimensions are the ones that fit your life, not just your car. Start with the standard minimums for clearance, then build out your plan from there. Your most important tool is a tape measure and an honest assessment of what you’ll actually do in the space. Before you finalize any plans, walk through these key points:

• Stick to a minimum of 12 feet wide by 22 feet deep for a vehicle alone.
• Add at least 3 extra feet of depth if you plan to work on projects or add storage in front of the car.
• Plan your wall storage and workbench layout on paper first to avoid a cramped, cluttered feel.
• Always check with your local building department for specific code requirements and permits.