Garage Cost Calculator - Attached or Detached Build

Typical U.S. range	$50–$200 per sq ft
Typical sizes	About 288 sq ft single, 480 sq ft double
Cost split	About 40% labor, 60% materials
Big add-ons	Slab, driveway, doors and electrical

What is Garage Cost Calculator?

A garage is a small building, whether it is attached to the house or standing on its own, and it carries the same cost structure: foundation or slab, framing, roof, siding, a large vehicle door, an entry door, electrical and a finished or unfinished interior. Because garages are usually unheated and simply finished, the price per square foot is lower than living space, but the building shell, slab and overhead door are still substantial items. Attached garages share a wall and roofline with the house and cost less to build than a detached structure of the same size, which needs its own foundation, roof and utility runs.

Common uses for Garage Cost Calculator

Budget a new detached garage before you call builders
Compare an attached garage with a detached one of the same size
See how much a finished, insulated interior adds over a shell
Price an oversized two-car build or a garage conversion

Attached versus detached

An attached garage shares a wall, part of the roof and usually the electrical service, which keeps costs down and makes access convenient. A detached garage duplicates all of that but buys flexibility: you can place it at the back of the lot, keep noise and exhaust away from bedrooms, and later convert it without touching the house. The price difference is real, and the calculator applies an editable multiplier for it.

What the square-foot rate does not include

Most per-square-foot figures describe the structure: slab, framing, roof, siding, a basic door and rough electrical. They rarely include the driveway, landscaping repair, trenching for power or water, the overhead door and opener, insulation, drywall or heating. On a detached garage those extras can add a large percentage to the total, so list them separately. Ask your builder to quote each of them explicitly rather than lumping them together.

Planning the size you actually need

A single-car garage is commonly around 12 by 24 feet, and a double around 20 by 24 feet, but modern vehicles and storage needs push many people larger. Extra width is usually cheaper than extra depth once you are building, and a taller ceiling allows a lift or overhead storage later. Decide the size before foundations are poured, because it is the one thing that cannot be changed cheaply.

Frequently Asked Questions

How much does it cost to build a garage?

Typical figures run from about $50 per square foot for a basic unfinished shell to $200 or more for a large, finished, well-equipped garage. Attached builds cost less per square foot than detached ones because they share a wall, roofline and utility connections with the house.

Is it cheaper to build an attached or detached garage?

Attached is usually cheaper for the same footprint. A detached garage needs its own foundation, roof, siding on all sides and often a separate electrical feed and driveway. It does, however, give you more flexibility about placement and keeps vehicle noise and fumes away from living space.

Does the price include the driveway and doors?

The unit price covers the structure, so treat the driveway, apron, overhead door, opener and any electrical trenching as separate items. Those can add a significant amount, and on a detached garage the driveway alone may rival a quarter of the build cost.

Do I need a permit to build a garage?

Almost always, and inspections typically cover the footing or slab, framing, electrical and final completion. Many jurisdictions also limit garage size, height and how close it can sit to a property line. Confirm the rules before design work, because they shape what you can build.