Detached Garage Cost per Square Foot: What Homeowners Actually Pay
If you are pricing out a new garage, the number you keep circling back to is detached garage cost per square foot. Most contractors will quote you between $40 and $70 per square foot for a standard detached garage, with simple, unfinished builds landing at the low end and heated, finished spaces pushing well past $100. That spread matters more than any single national average, because the finish level, the foundation, and your ZIP code move the final number more than the raw size does.
A detached garage is a self-contained structure, so every dollar you spend goes toward walls, a roof, a slab, and electrical that an attached garage would partially borrow from your house. Cost guides from Angi and This Old House track this same range, which is a good sign the number holds across regions. The trade-off is real flexibility: you can size it for a workshop, a home gym, an RV, or a rentable ADU down the line. The catch is that flexibility costs money, and it costs money on a per-square-foot basis you can actually plan around.
Here is how the math breaks down, what drives the price up and down, and where you can cut costs without ending up with a shed that leaks.
What a Detached Garage Typically Costs per Square Foot
The most honest answer is a range, not a single figure. Across the US, you should budget $40 to $70 per square foot for a conventional detached garage built to local code. That covers a poured concrete or gravel-on-slab foundation, wood or metal framing, a standard 16-foot-wide overhead door, basic roof, siding, and one electrical circuit for lights and the opener.
Here is what that range looks like against the three common footprints:
| Garage Size | Dimensions | Square Footage | Typical Cost Range |
|---|---|---|---|
| 1-Car | 12 x 20 ft | 240 sq ft | $9,600 – $16,800 |
| 2-Car | 24 x 24 ft | 576 sq ft | $23,000 – $40,300 |
| 3-Car | 36 x 24 ft | 864 sq ft | $34,500 – $60,500 |
These numbers assume standard 8-foot walls and no second story. The moment you add insulation, drywall, a heater, or a workspace, the per-square-foot cost climbs because you are finishing interior space, not just enclosing it.
The $40-per-square-foot floor gets you a simple, functional structure with the basics. The $70-per-square-foot ceiling gets you better materials, a more finished interior, or a region with high labor rates. When you see quotes below $40 per square foot, read the itemized breakdown carefully — something is usually missing, like the slab, the door, or the electrical rough-in.
Photo by Robert So via Pexels
Average Cost by Garage Size
Size is the single biggest line item, so it is worth looking at each format on its own. A bigger garage is almost always cheaper per square foot than a smaller one, because the fixed costs — the concrete truck, the framing crew, the permit, the grading — get spread over more area.
One-Car Garage
A 12-by-20-foot single garage runs $9,600 to $16,800 in most markets. This is the classic starter build: room for one vehicle, some shelving, and not much else. It costs the most per square foot of the three because the foundation and roof work barely get cheaper at this scale, but it makes sense when your lot is narrow or your budget is tight.
Two-Car Garage
The 24-by-24-foot two-car garage is the sweet spot for resale value. At $23,000 to $40,300, it gives you two parking stalls plus storage along the walls, and it is the size most appraisers and buyers expect on a single-family lot. If you want a modest workbench and tool wall, this is generally the smallest footprint that delivers it without crowding the cars.
Three-Car and Oversized Garages
A 36-by-24-foot three-car garage runs $34,500 to $60,500, and anything larger — a tandem bay, an RV door, a shop area — pushes you further up from there. Taller walls (10 or 12 feet instead of 8) also add cost, since you are buying more siding, more framing, and a steeper or larger roof. If you plan to park a lifted truck, a boat, or a camper, spec the door height up front rather than retrofitting later.
What Drives the Price per Square Foot
Two garages with identical footprints can land thirty to forty percent apart in price. These are the variables doing most of the work.
Foundation and Site Prep
A car and a truck weigh a lot, and they do not forgive a bad slab. You need either a thickened-edge monolithic pour or a frost-wall foundation with a 4-inch slab, and both require grading and, often, some fill. Bob Vila’s breakdown is a solid cross-check on concrete and site-work pricing. Flat, clear lots are the cheapest; sloping lots, rocky soil, or poor drainage can add thousands before a single wall goes up.
Framing and Materials
Standard wood stick-framing with a gable roof is the price baseline. Upgrades like steel framing, engineered trusses for a clear span, or a hip roof all add cost. Siding matters too — vinyl is the budget option, engineered wood and fiber cement sit in the middle, and brick or stone veneer is strictly a premium choice.
The Garage Door
The overhead door is a surprisingly large line item. A basic 16-by-7-foot steel door runs about $1,200 to $2,500 installed, while an insulated door, a taller door for a truck, or a second side door adds hundreds to thousands. If the garage is attached to your living budget for an apartment above, a detached garage with apartment cost is a different animal entirely.
Electrical, Insulation, and Finishes
Code requires at least a light and a GFCI-protected outlet. Every addition — a 240-volt circuit for a welder or EV charger, insulation and drywall, heating, a mini-split, finished flooring — adds to the per-square-foot figure. This is where most budgets quietly overshoot.
Finish Levels and How They Change the Price
The easiest way to think about your budget is by finish level. Each step up the ladder adds roughly $15 to $25 per square foot.
| Finish Level | What You Get | Price per Sq Ft |
|---|---|---|
| Basic Shell | Slab, framing, roof, siding, one door, one circuit | $40 – $55 |
| Semi-Finished | Insulated walls, some drywall, extra outlets, better door | $60 – $80 |
| Finished Shop | Fully drywalled, heated, sealed floor, lighting package | $85 – $110 |
| Dwelling-Ready | Insulation, plumbing stub, HVAC, egress, underslab work | $120+ |
A basic shell is a perfectly good car park. A finished shop is a second room. Understanding which one you actually need is the fastest way to keep your cost per square foot on target.
Detached Garage vs. Attached: Where the Money Goes
A detached garage almost always costs more per square foot than an attached one, and the reason is simple: an attached garage shares at least one wall, the roofline, and often the electrical and heating load with your house. You pay for three or four walls instead of one or two.
The trade is independence. A detached garage can be placed where it suits the lot, you can run loud tools or paint fumes without affecting the house, and it can be converted later into a workshop, studio, or ADU without disturbing the main structure. If you are still deciding which layout fits your property, this breakdown of the detached garage vs. attached garage cost walks through the numbers, and our guide to the detached garage cost to build covers the full project from permit to finish.
Photo by Curtis Adams via Pexels
Ways to Lower Your Cost per Square Foot
You can trim the per-square-foot number without sacrificing the structure itself.
- Standardize your dimensions. Framing and sheathing come in 4-foot and 8-foot modules. A 24-by-24 footprint wastes almost nothing; a 23-by-23 one does not save money, it creates offcuts.
- Build up, not out. A second story or a storage truss adds usable space for less per square foot than widening the footprint, since the foundation cost stays fixed.
- Use a 4-inch slab with thickened edges. A full foundation wall is overkill for a simple garage in most climates and code jurisdictions.
- Stick to one overhead door. Each additional door means more framing, more hardware, and another opener.
- Finish the interior later. Rough in the electrical now, add insulation and drywall next year when the budget recovers.
- Get three itemized quotes. Contractors price the same garage very differently. Compare line items, not just the total.
Frequently Asked Questions
Is a detached garage cheaper than an attached garage per square foot?
Usually the opposite. Because a detached garage needs its own walls, foundation, and electrical service, it tends to cost more per square foot than an attached garage that shares structure with the house. The savings come later, in flexibility and in how it affects your living space.
How much does a 24×24 detached garage cost?
A 24-by-24-foot (576-square-foot) detached garage typically runs $23,000 to $40,300, depending on finish level and labor rates in your area. A basic shell sits near the low end; a heated, drywalled build trends toward the high end.
What is the cheapest detached garage cost per square foot?
Plan on about $40 per square foot as a realistic floor for a code-compliant, contractor-built garage with a slab, standard door, and basic electrical. DIY builds, pole-barn construction, and metal kits can dip lower, but those trade durability and finish for savings.
Do I need a permit for a detached garage?
Almost always, yes. Detached garages are governed by the same building codes as other structures — setbacks, frost-depth foundations, wind and snow loads, and electrical requirements all apply. Skipping the permit can void your insurance and complicate any future sale.
Does a detached garage add value to a home?
Yes, when it is sized and placed sensibly. A two-car detached garage is one of the more reliable projects for recovering cost at resale, and in many markets buyers see it as a must-have rather than a bonus. A DIY-grade or oversized oddity is less likely to pay back.
The Bottom Line
Detached garage cost per square foot is a useful planning number, but it is not a fixed price. Expect $40 to $70 per square foot for a standard build, with the final total set by size, foundation work, finish level, and local labor. A simple two-car garage will land somewhere around $23,000 to $40,000; a finished shop or a dwelling-ready structure will push well beyond that.
The smartest move is to decide what the building is for before you draw a line. A car park, a shop, and a future apartment are three different budgets wearing the same name. Lock in your dimensions, get three itemized quotes from licensed contractors, and hold the finish level until the shell is up and paid for. For a fuller picture of the whole project, see our guide to the detached garage cost to build and how a detached garage with apartment cost compares if you are thinking a step ahead.
