How Much Does a Garage Extension Cost? [2025 Data]
Building a garage extension costs $10,000 on average but ranges between $3,500 and $14,000, depending on the size, scope, and details of the project.
If you’re adding more space to your existing garage, you can expect a garage extension cost of around $10,000, with costs commonly ranging from $3,500 to $14,000 or more. Building a garage extension is an excellent way to give yourself more space for work, recreation, and storing your belongings. To ensure you build an area that suits your specific needs, it's important to understand all the garage extension costs. Here's a close look at what to expect when making your plan.
How Much Does It Cost to Extend a Garage per Square Foot?
The cost to extend a garage is about the same cost to build a new garage and similar to the cost to remodel a garage. That's because the project requires all the same steps, from pouring a new foundation to installing a new roof.
On average, a garage extension costs $40 to $70 per square foot. If your project requires knocking down an exterior wall, expect to pay on the higher side.
Here are some common garage sizes and configurations when extending a garage, including total project costs:
| Project | Size of Extension (Ft.) | Cost |
|---|---|---|
| Convert 1 car to 2 car | 8-by-20 | $6,400–$11,000 |
| Convert 2 car to 3 car | 10-by-20 | $8,000–$14,000 |
| Convert 1 car to 3 car | 22-by-22 | $19,360–$33,800 |
Garage Extension Cost Breakdown
When determining how much you'll spend to extend a garage, you'll find that you can divide project costs into preparation, demolition, and building.
Design
As your garage extension will involve some level of new construction, it's wise to hire a structural engineer to review your design plans and help you draw up blueprints. The cost of hiring a structural engineer is 1% to 20% of your project budget, which translates to $200 to $1,500 for a build of easy to medium complexity.
Permits
Many municipalities require construction permits when you renovate your home. These permits pay for recording your improvements in official documents and later inspections to ensure soundness. Depending on your area, permitting may cost you $200 to $1,500.
Demolition
Depending on how exactly you intend to extend your garage, it may be necessary to complete some demolition. This will be the case if you add on to your garage width-wise, as you'll need to knock down part of an exterior wall to build outwards.
As all exterior walls are load-bearing, the cost to remove a wall ranges from $1,200 to $3,000. Aside from the complexity of working with load-bearing walls, there may also be plumbing and electrical concerns within walls, so it's always best to leave this type of work to a professional.
General Contractor
If you don't plan to manage the construction of your garage extension, you'll need to hire a local contractor to oversee the project. You'll pay this professional 10% to 20% of the overall project cost to manage things for you.
Foundation
The cost of building a foundation for your garage to sit on will range from $4 to $25 per square foot, depending on the type you need. A monolithic concrete slab will usually work, but local conditions could require a stem wall slab or pier and beam construction instead.
Framing
Framing involves building out the new skeleton for your garage addition. When you hire a local framer, you can expect to pay $4 to $8 per square foot for new walls and beams.
Electrical
With new square footage in your garage extension, you'll likely need more electrical outlets to power tools and other accessories. You may also need wiring throughout the walls and ceiling for light fixtures, garage doors, and alarms. The average cost to hire an electrician is $50 to $100 per hour.
Plumbing
When you build onto your garage, you may find yourself with room for a new washtub or even your washer and dryer. As an exterior wall may have been demolished or moved, you might also need a new spigot outside for a hose. The cost to hire a plumber to add new piping and fixtures runs from $45 to $200 per hour.
Roofing
The cost of roofing your garage can range from $1,000 to $3,000, mostly dependent on whether your contractor can simply add on to your existing roofline or needs to remove the old roof and build a new one.
Garage Door
One of the final steps of extending a garage may include adding a new garage door or replacing your existing one with something larger. This may be a necessity if you build your garage wider or extend the front of it, but you might not need it if your construction took place at the back of the garage. The cost for garage door installation runs from $750 to $3,000, depending on whether you need to add a door, upgrade to a two or three-car unit, or need a new opener. The local garage builder you hire can often handle this step of the project. However, the builder may subcontract the work.
Exterior
| Siding Type | Cost Range (per Sq. Ft.) |
|---|---|
| Stucco | $7–$9 |
| Vinyl | $3–$12 |
| Wood | $1–$15 |
| Brick | $10–$20 |
| Stone | $7–$30 |
| Fiber Cement | $5–$14 |
Once the garage is built, it's time to turn your attention to finishing it out. In most cases, your existing home finish will determine what you'll use for the garage. For example, if your home has a stucco exterior, you'll likely continue that with your garage. The same applies if you have cedar or vinyl siding. Assuming you have a stucco exterior and drywall or cinder block interior, at the very least you'll need to pay for painting. If you hire a pro, expect to pay $1 to $6 per square foot to paint the interior and exterior.
Extending a Garage Yourself vs. Hiring a Pro
On average, it costs $40 to $70 per square foot to extend a garage. Labor alone makes up 50% to 70% of the finished project cost, meaning you save $20 to $50 per square foot if you do a DIY renovation.
To break this down further, let's consider a garage extension of 200 square feet, which is about what you'll do if you extend a garage to hold three cars rather than two. If you pay a professional to do the job, you'll spend $8,000 to $14,000 in material and labor costs. However, if you complete the project on your own, you could spend as little as $4,000 just for materials.
There's no doubt that completing a garage extension on your own can result in significant savings, but just looking at numbers doesn't offer a real appreciation for the hard work that goes into the construction project. Extending your garage requires significant skill as you'll be dealing with load-bearing walls, electrical, and general construction. Not getting a building project right can present a significant danger to yourself and anyone who enters your home. Unless you're a pro, this really is a job better left to those who are more qualified.
Tips to Reduce Costs While Extending a Garage
There’s no getting around it: the cost to add a garage to the side of the house or to extend an existing garage can be expensive. Here are some tips to keep prices down:
Limit the project scope: If you currently have a one-car garage, it will be much more affordable to extend it to a two-car garage rather than three. However, if you need a larger three-car garage, there’s no getting around this.
Avoid extras: If your garage does not currently have features like plumbing and heating, you’ll have to hire a plumber to install plumbing for appliances like a washer, dryer, or utility sink and a local HVAC specialist to extend ductwork into the garage or install a separate heating system. If you don’t need these features, skip them altogether to save money. Plus, you would need to insulate a garage with plumbing and heating—and the cost to insulate a garage (especially one made larger by extending) would drive up the price further.
DIY part of the project: Extending your garage is a challenging project, and one that absolutely requires professional contractors. However, you can cut some costs by taking on some of the easier work yourself, such as drywalling, installing the garage door opener, and, if you’re a more experienced DIYer, even adding the exterior siding yourself. You may also be able to handle the demo, junk removal, and insulation—here’s how to insulate your garage on your own.
Get multiple quotes: As with any major construction project at home, we recommend getting quotes from at least three contractors. Assuming all the contractors have strong reviews, proper certifications and experience, and similar timelines, you can hire the one with the lowest bid.
How Angi Gets Its Cost Data
Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We extensively research project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We rely on reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects.
Want to help us improve our cost data? Send us a recent project quote to costquotes@angi.com. Quotes and personal information will not be shared publicly.
Frequently Asked Questions
It makes sense to extend your garage if you need more room to work or store your belongings. In addition to having that extra breathing room, you don't have to worry about the money you spend on the project going down the drain. As far as the value a garage adds to a home, you can often recoup 75% to 85% of your investment into a garage extension or garage bump-out addition.
The cost to tear down a garage averages $2,000 to $10,000. You might consider this option if your existing garage is damaged beyond repair or if you have grand renovation ideas that are best suited to a fresh build.
Other ways exist to increase the usefulness of your garage space. There are even options for turning your carport into a garage. Another method is to extend the length of your garage by making it deeper. The process is similar to traditional garage extensions. However, the end product is a garage with a different floorplan rather than additional parking spaces to accommodate more storage or other space.
