How Much Does It Cost to Build an Outbuilding in 2025?
Outbuilding construction costs an average of $9,500
The average cost to build an outbuilding ranges from $13,000 to $33,000, with most homeowners spending an average of $9,500.
Structure size, materials, and design complexity are the biggest drivers of cost.
A well-built outbuilding can boost curb appeal and raise resale value.
Adding an outbuilding gives you flexible space for storage, hobbies, or even guest quarters.
This article was updated using automation technology and thoroughly reviewed for accuracy by HomeAdvisor Editor Ryan Noonan.
On average, outbuilding construction costs $13,000 to $33,000, averaging $9,500. You’ll pay $20 to $150 per square foot, depending mostly on materials and prefab or custom.
Building an outbuilding gives you custom storage, workspace, or living space. Bringing in a pro helps you secure permits and build a durable structure that lasts.
Outbuilding Construction Cost Factors
How much you spend to build an outbuilding depends on a variety of factors. Here’s a closer look at how your costs break down.
Outbuilding Type
The type of structure you build plays a significant role in your cost. Here are the average prices for various types of outbuildings.
| Outbuilding Type | Average Cost |
|---|---|
| Barn | $14,000–$96,000 |
| Shed | $1,000–$15,000 |
| Greenhouse | $3,000–$16,000 |
| Workshop | $18,000–$45,000 |
| Garage | $20,000–$45,000 |
| Guest house | $62,000–$100,000+ |
Structure Size
Plan to spend $20 to $150 per square foot when constructing an outbuilding on your property. You’ll land on the higher end if you choose premium materials like brick or add finishes such as HVAC or plumbing.
| Size (Sq. Ft.) | Average Cost |
|---|---|
| 120 | $2,400–$18,000 |
| 400 | $8,000–$60,000 |
| 600 | $12,000–$90,000 |
| 800 | $16,000–$120,000 |
| 1,000+ | $20,000–$150,000+ |
Labor
Hourly rates for professional labor range from $50 to $150, depending on the type of contractor you hire. If you hire a general contractor for your project, you’ll pay a percentage of the total cost, with rates ranging between 10% and 20%.
Plan on spending more on labor if your outbuilding requires an electrician, HVAC technician, or plumber. You’ll also pay more for labor if you live in a high-cost-of-living area where pros often command higher prices.
Building Permits
A building permit costs $200 to $2,000, depending on your location and project size. Most cities require a permit before you break ground on a second structure. Rules vary—setbacks, height limits, and distance from the main house all come into play. Ask your pro whether they’ll pull the permits for you. If you’re in an HOA, you’ll also need its approval.
Prefab vs. Custom Structures
Expect to pay $20 to $150 per square foot, including labor and materials. Prefab kits land on the lower end, while custom builds sit at the top thanks to added design work and high-end finishes.
Ways to Save on the Cost to Build an Outbuilding
Consider these cost-saving strategies to make your outbuilding construction project more budget-friendly:
Get detailed quotes from multiple general contractors in your area to compare rates and ensure competitive pricing.
Schedule your job in the off-season to take advantage of potential discounts.
Choose simple design plans over more expensive custom builds.
Opt for less expensive materials and finishes instead of higher-end ones.
How HomeAdvisor Gets Its Cost Data
No place is more important than your home, which is why HomeAdvisor connects homeowners with local pros to transform their houses into homes they love. To help homeowners prepare for their next project, HomeAdvisor provides readers with accurate cost data and follows strict editorial guidelines. After a project is complete, we survey real customers about the costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from 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.
