How Much Should a Garage Extension Cost?

You may consider a garage extension if you purchased a larger vehicle than your previous one. A garage extension can also turn your garage into a home office, dining room, entertainment center, home gym, kitchen, bedroom, or play room. Bear in mind this is not a low-budget project. We’ll detail some of the basic expenses below, in addition to various factors that can impact your garage extension cost.

Total Cost of a Garage Extension

According to HomeAdvisor, it costs $27,984 on average to build a garage (with a general range of $16,994 to $39,308). This equates to about $40 to $70 per square foot. But, it can cost $50,000 or more to build or expand your garage, depending on many variables. It can pay off to have a larger, more functional garage, both in terms of your experience and the impression it can have on potential home buyers down the road.

Factors to Consider

• Size: Construction contractors often bid on garage projects based on size. A one-car garage is usually at least 12×20 feet. A two-car garage is at least 20×20 feet. The larger the garage, the higher the basic cost of building an extension, and many people choose larger dimensions such as a 24×24-foot garage. But keep in mind size is just a starting point in determining the ultimate cost.
• Attached/Detached Garage: Complexity will certainly add to the cost. An attached garage is well-suited for small lots and homeowners who want direct access to their homes (especially when adding living space). Detached garages can be expanded as well, and you may have more choices in terms of layout, style, and size. They often require more materials and labor to modify. But here’s another garage extension cost factor—engineering help, as hiring a professional can cost a few hundred to up to $5,000 or more.
• Structural Elements: If you’re starting from scratch, a foundation can cost from $1,600 to $2,000, for a 20 x 20-foot garage. Excavation work will add to the cost. But you can lower the cost if the new garage is built on the same site as the old one, or little demolition work is required. And location is a factor here; you can build or keep an on-grade concrete slab if the ground doesn’t freeze, but if it does, you’ll need a footer below the frost line.
• Materials: All the materials used will add to the garage extension cost, and can include:
  • Siding: Aluminum siding ranges up to $7, brick up to $15, Hardie board up to $5, and natural stone up to $50 per square foot. Vinyl siding averages roughly $4 per square foot as does cedar siding, a visually appealing and environmentally sustainable option. Durable fiber-cement siding averages about $10 per square foot. If you want to refurbish the side of your garage with brick, it can cost up to $9 per square foot.
  • Flooring: Expect to spend $0.15 to $25 per square foot on flooring, depending on the material. Laminate flooring is about $2 to $5, but in the mid-range, vinyl flooring costs $2.50 to $5.50, engineered wood from $3.50 to $7, and Oak from $8 to $15 per square foot. Natural tile flooring ranges from $10 to $25 per square foot on average.
  • Roofing: If you have beams and columns in the middle, they can interfere with the finished space’s functionality. Removing these involves labor and potentially redoing the roof, and new roof trusses and beams vary in cost depending on lumber prices. Roofing ranges from $1 To $15 per square foot; asphalt shingles run up to $3.50, wood shingles up to $5.50, metal up to $6, and slate up to $15.

Framing is another factor. It can run, with materials and labor, from $15 to $30 per square foot if your garage frame needs to be expanded. Lumbar generally starts at $250 per 1,000 board feet; however, costs do fluctuate. Wood averages $1 to $5 per square foot and a steel frame averages around $2 to $6 per square foot in 2022.

• Project-Related Costs: The garage extension cost can increase with various fees, which can include:
  • Architect Fees: An architect can charge from $2 to $25 per square foot, or from $125 to $250 per hour.
  • Architectural Plans: Custom planning can take a lot of time and effort. However, you can save with premade plans (cost between $500 to $1,000).
  • Permits: You’ll need a garage building permit, which can range from $1,200 to $1,500. However, permitting costs vary by location; according to the National Association of Homebuilders, permit fees typically account for 1.7% of the total project cost.

Other Garage Extension Costs

In addition to materials and labor, other costs you may incur include those for materials delivery, debris removal and disposal, and for protecting existing structures on your property. Modifications to your electrical and plumbing system add to the final cost as do HVAC, insulation, lighting, and security elements. Project management is another factor. Your project can cost 15% to 23% more to have someone supervise construction. And don’t forget the sales tax on materials and supplies in your state.

Schedule Your Consultation and Estimate with Mesa Garage Doors

We install high-quality garage doors throughout Southern California. Specializing in leading-brand garage doors and garage door openers, our factory trained installers and repair technicians do all it takes to ensure your satisfaction. Call 800-893-1107 to schedule an estimate on work related to your existing garage or an extension.