Profile picture of Alan Bernau Jr
Call Us
1-800-488-6903
Free delivery and quick, free installation
Small deposit to order
20-year warranty on 12-gauge orders

Get your custom garage at our factory direct prices with free delivery and installation!

Customize Now, It's Free

Get custom buildings with
free delivery and installation!

Customize Now

4-Car Garage: Detached Tandem or 4-Bay Options

A photo shows a long, single-story metal garage with four white roll-up doors on the front and dark gray siding. The building sits on a dirt lot with trees in the background.

Need to shelter four vehicles in a detached garage? These four-car garage layouts often start around 20×40 and can scale up to roomier footprints like 24×50 when you want more storage space, a workspace, or a garage workshop. Choose a 4-bay layout for easy access to each vehicle, or a tandem garage when your site is tighter, but you still want extra space.

We have two different base plans for a 4-car garage. The first is a 4-bay design. The second is a tandem (double-deep parking) design. These detached, prefab metal garages are fully customizable, and either one is a cost-effective way to protect your growing car collection.

Get a Custom Metal Building at Unbeatable Factory-Direct Prices

Instant Online Pricing

Exact price online for metal buildings—no calls, no forms.

Free Delivery & Installation

We deliver and install at no extra cost in our service areas.

Certified Quality

U.S.-made steel, 1-year workmanship warranty.

100,000 Satisfied Customers

23+ Years of Factory Direct Prices

4-Bay, 4-Car Garage

A diagram titled “4-Bay, 4-Car Garage” shows four cars parked side by side inside a rectangular garage labeled 40 feet long and 20 feet wide. Dimension arrows and measurements illustrate the layout, with the Alan’s Factory Outlet logo in the corner.

Approximate layout example only; exact fit depends on vehicle size

Our 4-bay design has four separate garage doors on the side of the garage. This is a good layout if you have plenty of space on your property and want a separate garage door for each vehicle for easy access.

The minimum dimensions for a 4-car garage are 20×40. The garage doors should be placed on the side of the building instead of the front. The reason for this is architectural: a 20-foot-wide building has a roof that is much smaller and less expensive than the roof of a 40-foot-wide building.

Side entry doors can also improve functionality on wide garage sites by keeping the front elevation cleaner and helping traffic flow on larger driveways.

A 4-bay garage design gives you a few ways to set up your garage doors, depending on how you use the garage space and how you want vehicles to enter:

  • Four single garage doors for dedicated access to each vehicle
  • Two double garage doors if you prefer fewer openings and a simpler look

Our 20×40 4-car garages start at about $13,500. Use our online design tool to get the exact price for your location and options.

A diagram titled “4-Car Garage With Workspace” shows a 50-foot-long, 24-foot-wide garage with three cars parked in a row and one vehicle in a deeper bay. Labeled areas indicate a storage section and a workspace along the back wall.

If you have any larger vehicles or if you want additional storage and workspace in your 4-car garage, we recommend a floor plan that is at least 24×50. This design has 1200 square feet of space, which is 50% more than a 20×40 garage. You’ll definitely notice the difference.

Our 24×50 4-car garages start at about $18,000.

Get an Instant Quote for Your Custom Carport

Select Your Building Type
Select Your Roof Style
Choose Frame Size

Price may vary based on doors, windows, height, and other add-ons.

Size and Square Footage for a 4-Car Garage

Square footage is one of the quickest ways to compare a 4-car garage layout. Even small changes in width or length can make the garage space feel much easier to park in, walk through, and use for storage.

Here are a few common footprints and their approximate square footage:

  • 20×40 = 800 square feet for simple vehicle storage
  • 24×40 = 960 square feet for more walking room around larger vehicles
  • 24×50 = 1,200 square feet when you want a storage area plus a dedicated workspace

If you’re comparing options by sq ft, focus on how you’ll use the building day to day. Vehicle width, door clearance, and how much extra storage you plan to have inside can all affect what size feels comfortable. If you want room for tools, shelving, or a garage workshop setup, moving up in square feet will make the layout more flexible.

4-Car Tandem Garage

Detached 4-bay metal garage with four wide openings, ideal for parking four vehicles with side-by-side access and extra storage space.

If your property isn’t wide enough for a 4-bay garage, a tandem garage may be right for you. With the tandem design, you park one car behind another, so you only need two single garage doors. The disadvantage of this plan is that you need to move the cars parked in the front before you can drive the cars in the back of the garage.

However, if you have a driveway behind your garage, you can add garage doors on the back side to create a drive-through design. This type of tandem garage layout can be especially helpful on narrow lots where you want 4-car functionality without widening the building footprint.

When a Tandem Garage Works Best

A tandem garage often fits well on long, narrow properties where a wide 4-bay design would crowd the yard or driveway. If your driveway runs along the side of the house or behind it, a tandem layout can give you extra parking space while keeping more of the yard open in front.

Adding rear doors can also make it easier to pull straight through, which improves day-to-day functionality. You can even use part of the interior as a small garage workshop or workspace if you don’t need to park four vehicles all the time.

4-Car Tandem Garage Floor Plan

If you choose a tandem design, we recommend making it at least 24 feet wide, so you’ll have plenty of space to walk around your largest vehicles. If you also need storage space or a place to work on your cars, you can make your design longer or wider.

A diagram titled “4-Car Garage With Workspace” shows a 50-foot-long, 24-foot-wide garage with three cars parked in a row and one vehicle in a deeper bay. Labeled areas indicate a storage section and a workspace along the back wall.

A 24×40 tandem garage starts at about $14,000. Use our online design tool to get the exact price for your location and options.

4-Car Garage Plans and Floor Plans

Many homeowners start their search with 4-car garage plans because they want to picture the layout before they commit to a size. As you compare floor plans, consider these decisions:

  • How much space you want for parking versus extra storage
  • Whether you want a garage workshop zone or a clear, open floor
  • Where a walk-in door should go for day-to-day access

Some homeowners come in searching for 4-car garage plans or even garage house plans. If your concept includes living space or a finished area, your designer will care about details like the main floor layout, a half bath, a crawl space vs. slab approach, or even features like a walk-in pantry in a larger outbuilding plan.

Our metal buildings are designed so that the garage shell and layout flexibility allow you to start with a plan that fits your property and then adjust the details to match how you’ll use the space.

How Much Does a Concrete Slab for a 4-Car Garage Cost?

Concrete slab pricing depends on local labor rates, slab thickness, reinforcement, site grading, and frost-depth requirements, so the same square footage can come out very differently from one area to the next.

As a general starting point, many basic slabs fall in the range of roughly $4–$8 per sq ft, while thicker, reinforced slabs can run higher.

Using that range, here are ballpark examples you can expect based on common 4-car garage sizes:

  • 20×40 (800 square feet): About $3,200–$6,400
  • 24×40 (960 square feet): About $3,840–$7,680
  • 24×50 (1,200 square feet): About $4,800–$9,600

A local concrete contractor can confirm what your site needs and quote the slab based on your layout, soil conditions, and the load you expect the garage space to handle.

Concrete Pad Size Calculator

Use this calculator to estimate the concrete pad size required for your building.

Customize and Buy Online
Choose Your Frame Size
Width
Length
Recommended concrete pad size for your 12’ x 20’ metal building: 13’ x 21’
Customize and Buy Online

Compare Garage Sizes: 1-Car to 6-Car

Garage size usually comes down to how much garage space you want for parking, storage, and day-to-day use. If you’re looking at storing more than just cars, these garage sizes are also available:

  • 1-car garage: Fits one vehicle with a small area for tools or seasonal items.
  • 2-car garage: Works well for daily drivers, plus room for basic extra storage along the walls.
  • 3-car garage: Adds a flexible extra bay for a third vehicle, a small workspace, or larger equipment.
  • 4-car garage: A strong fit for car collectors, a garage workshop setup, or multi-use storage and parking.
  • 5-car garage and 6-car garage: Often chosen for larger properties where you want more dedicated zones for vehicles, equipment, and storage.

If you only need overhead cover, a carport can be a simpler starting point.

About Our Metal Garages

Large beige metal garage building with three open bay doors and a side entry door on a concrete slab, set on a gravel lot with leafless trees in the background. Equipment and storage items are visible inside the open bays under a clear blue sky.

Alan’s Factory Outlet is a family-run business that provides high-quality, custom steel garages. The garages we sell are prefabricated in the USA and include free delivery and installation in our 21-state service area.



Our 3D Carport & Metal Garage Builder allows you to choose from dozens of customization options and immediately see the exact price you need to pay for your garage. If you have a growing car collection that you need to protect, here are a few practical choices to consider:

  • Choose light colors for maximum energy efficiency. Light colors reflect heat and can help keep your garage cooler.
  • Consider adding insulation to the roof or the whole garage. Roof insulation can help reduce condensation on the underside of the metal roof in cool weather, which helps protect vehicles and stored items.
  • Upgrade to 12-gauge steel tube framing if you live in an area with strong winds, or if you need higher strength and added durability in demanding conditions.

Roof Style and Durability

Roof style can affect runoff, ventilation, and how the building performs in your local weather. A roof style that sheds water and debris well can also make day-to-day upkeep easier, especially if you plan to use the garage year-round. Some homeowners might prefer craftsman styling or an A-frame silhouette when planning an outbuilding.

Our 3D garage metal building builder lets you choose the roof style options available for our metal garages, so you can balance garage design, functionality, and durability.


Frequently Asked Questions (FAQs)

A 4-car garage price depends on size, layout, and options. Our garages start around $13,500 for a 20×40 and around $18,000 for a 24×50. Your total garage price can change based on site work, permits, and whether you need a concrete slab or grading. Use the builder to see pricing based on your location and selections.

A common minimum footprint for a 4-car garage is 20×40, which is 800 square feet — though fitting four small cars will be tight. If you want more walking room, extra storage, or a workspace, larger layouts like 24×40 or 24×50 can make the garage feel more comfortable. The right garage size depends on vehicle width, door clearance, and how you want the space to function day to day.

It depends on your goals and timeline. A prefab metal garage can reduce on-site build time because it arrives ready to assemble, while a site-built garage may offer different design choices but often involves more local labor and scheduling. Either way, permits, site preparation, and foundation work can have a big impact on total cost.

In some areas, a very small, basic garage may come close to that price. For a larger 4-car garage, costs often rise once you include site work, permits, and the foundation. If $10,000 is your target, it helps to price a simpler layout first using an online 3D builder and then add options based on what matters most for functionality.

Sorry, we don\’t deliver to the selected zip code.
Your Zip Code helps us provide the exact price for your location as construction specs vary depending on code requirements for each state.

    Search results