Attached Garage Construction Cost Estimator

Building an attached garage addition costs on average $28,000 to $55,000, with the average homeowner spending around $42,000 on a 24’ x 24’ two-car garage with vinyl siding, an asphalt roof, and an unfinished interior. This project’s low cost is $20,000 for a 12’ x 20’ single-car garage with vinyl siding, an asphalt roof, and an unfinished interior. The high cost is $120,000 for a 24’ x 24’ two-car garage with brick siding, a slate roof, and a finished interior.

Attached Garage Construction Cost Estimator

Attached Garage Cost per Square Foot

They come in many sizes, impacting your project’s cost. They typically cost between $80 to $100 a sq.ft. for conventional building methods, with prefab garages costing between $50 and $70 a sq.ft. Technically, you could have your new attached garage built in any size, but there are a few standard sizes. For a one-car garage, the average size is about 12’ x 20’ or 240 sq.ft., while most people find that 24’ x 24’ or 576 sq.ft. is more comfortable for two cars, provided you have the room. You may opt for a larger size if you want to use it for more than parking.

SizeConventional Construction CostPrefab Construction Cost
12 x 20 Feet$15,200 – $22,400$10,200 – $15,600
16 x 24 Feet$27,040 – $35,720$18,260 – $24,140
14 x 28 Feet$24,710 – $33,590$16,480 – $25,820
20 x 20 Feet$26,000 – $34,000$18,000 – $26,000
24 x 24 Feet$36,320 – $48,380$25,340 – $35,760
30 x 20 Feet$38,000 – $52,000$26,000 – $38,000

Cost to Build an Attached Garage by Number of Cars

They can be built in many sizes. The most common method of determining size is usually correlated to how many cars you keep there. Generally, when sizing it, you want enough space to park the cars, fully open their doors, walk around them comfortably, and have some room for storage. That is why they can be built in different sizes, but there are also some standard sizes based on the number of cars. By opting for the standard size based on how many cars you park there, you can be fairly sure you have the space you need.

Attached Garage Construction Cost Estimator

1-Car Attached Garage Cost Estimator

The cost to build a single-car garage using conventional methods is $15,300 to $21,500. The cost to build this type of area using prefab construction is $19,400 to $15,600. It should have a minimum width of 12’ and a minimum depth of 20’. Consider enlarging these dimensions if you plan on using it for things other than parking. They are uncommon attached to homes but can be used for things other than parking.

2-Car Attached Garage Cost Estimator

The cost of a 2-car attached garage is $26,000 to $48,080 when built using conventional methods. The cost when building a prefab garage is $18,000 to $36,360. They are the most common size when building this type of area. The minimum size for this type would be 20’ x 20’, but most opt for 24’ x 24’ for the added space. If you have large vehicles and will need more space for door clearance, or desire extra space for storage or other activities, consider increasing the footprints.

4-Car Attached Garage Cost Estimator

The cost of building a 4-car attached garage is $52,000 to $75,400 for conventional construction. The cost of a 4-car prefab one averages $35,000 to $54,600. It will only be possible on a large piece of land due to the amount of space needed. They have several configurations and dimensions. The most common include 40’ x 20’ and 44’ x 20’. This is also a good size if you have the space and want to park two cars while also having enough room for a very large workshop or other home working or craft space.

Attached Garage Siding Material Cost

The average cost to install siding on a 2-car garage is $3,500 to $9,500, using vinyl siding. The exterior of your walls also needs finishing. Because the space is attached to the rest of your home, it is typical to use the same siding and trim material you have on the rest of your home to finish it. This produces the most cohesive look for the property and makes the garage look like it was built with the house, rather than as an add-on. This also means that any finish techniques, decorative trim, or accent material needs to be included on the garage’s facade as well.

Attached Garage Construction Cost Estimator

Enclosing an Attached Carport Cost

If you have a carport where you want your garage to be and that carport has a foundation, you can save some money over building it from scratch. The average cost of converting a carport to an attached garage is $20,000 to $35,000. This assumes the foundation can be reused, and some of the carport’s structure can also be converted. If you do not have a foundation for the carport or the structure cannot be reused, you need to remove it and start the project from scratch, increasing the costs to $25,000 to $50,000.

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Process To Get attached garage Cost Estimate Report

Here I am going to share some steps to get your attached garage cost estimate report.

  • You need to send your plan to us.

    You can send us your plan on

  • You receive a quote for your project.

    Before starting your project, we send you a quote for your service. That quote will have detailed information about your project. Here you will get information about the size, difficulty, complexity and bid date when determining pricing.

  • Get Estimate Report

    We do attached garage cost estimating and prepare a detailed report for your project. At last you finalize the report and finish the project.

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