How Much Does It Cost to Add a Second Story to Your Home in Chicago, IL? [2026 Data]

The cost to add a second story in Chicago, IL, ranges from $82,880 to $621,600, with an average price of $181,300. The size and type of your home addition are the main factors affecting your total price, since full-size stories require more involved structural engineering and building plans. Many homes in Chicago, IL, are also located in historic neighborhoods and are subject to additional permit and review costs.

Second-Story Addition Cost Factors

The cost to add a second story in Chicago, IL, depends on the size and type of your addition. Structural reinforcement, demolition, staircases, and other factors also contribute to your final price.

Second-Story Size

A second-story addition costs between $300 and $700 per square foot on average, but complex projects with high-end materials could reach even higher.

Addition Type

When you can picture your second-story design idea but can't quite put it into words, take a look at the costs by the type of addition. Every second story will be unique, but they typically fall into one of the following categories:

• Full second story: Building a full second story over your current layout comes with stiffer foundation requirements. You will also spend more on windows, roofing, insulation, and all of the homey features that round out your second floor.

• Partial second story: These additions are popular for their flexibility and comparatively lower costs. They may include a guest bedroom, an extra bathroom, or a flexible space for an office.

• Converting a vaulted ceiling into a second story: A vaulted ceiling adds lots of airy space to a house, but some see all that space and wonder if it could be used differently. If the ceiling is higher, it’s possible to convert it into a partial addition or loft to create usable space. 

• Dormer addition: A dormer is a triangular window space on top of a roof. Dormers cost less than full second-story additions but can expand an existing second story and give rooms more light and a bigger feel.

• Add a bonus room above the garage: When adding a room above a garage, square footage matters, but you'll also need to ensure the garage's structure can handle the extra weight. The second floor may also require additional insulation and vapor barriers.

Finish Quality

If you choose higher-end materials, such as stone siding or marble bathroom flooring, expect your costs to be higher than those of builder-grade materials. While some high-end materials reduce maintenance costs, many standard finishes are still durable and save money in the total project price.

Foundation Reinforcement

Depending on the structure of your existing home, your foundation may not be strong enough to support a second-floor addition. You'll want to hire a local structural engineer to evaluate your foundation and determine what you may need to strengthen it.

Foundation support work costs $1,500 to $7,000. Where you live, seasonal weather patterns, and ground characteristics all factor into the amount of work needed. 

Demolition

In many cases, building a second story requires that your contractor remove the roof and then open up walls and ceilings to reinforce your home’s framing. Removing a room costs an average of $1,295, and the cost to replace the roof when all is said and done usually falls between $6,050 and $14,515. While designers often work around existing chimneys, the price to remove a chimney for a second story adds an average of $4,660.

Adding a Staircase

Installing the main staircase in your home costs between $2,485 and $4,145, but high-end designs can reach $6,220. General contractors will often include this price in the second-story price estimate, as it's a crucial element of the design. However, the placement of your stairs, the design, and additional elements like carpeting can raise the price.

Landscaping

While not as common, the landscape surrounding your home may change when you add a second story. Construction equipment can damage your lawn, garden, and surrounding trees. Due to a shift in the shadows of your lawn, you may choose to move certain plants and flowers that sat in direct sun before the build. Professional landscaping costs between $40 and $70 per hour.

Temporary Housing

For safety purposes, you'll need to be out of your house during the construction of your second-story addition. A partial addition can take three to six months to complete, while a full second-story addition can take six to 12 months. If you don't have a nearby relative or a motorhome to stay in, factor in the cost of a rental into your project.

Home Builder Pro Costs

Hiring a local home builder in Chicago, IL, will come with different costs according to labor rates, taxes, permits, and other factors.

Labor

Labor accounts for 40% to 60% of the total cost of a second-story home addition in Chicago, IL. Home builders or general contractors also charge 10% to 20% of the total project cost as their fee, covering oversight of the entire project, including materials, crews, and permits.

The city also has a strong union labor presence and a competitive labor market for tradespeople, both of which can drive up costs. Project complexity, as measured by the Project Complexity Scale, also determines how many workers or specialized professionals are needed, so older brick homes, accessibility challenges, structural modifications, and other factors common in Chicago, IL, can further increase labor costs.

Cost of Living

The cost of living in Chicago, IL, is about 18% higher than the national average, which also affects residential construction rates. Materials, wages, and other operating expenses correlate to the cost of living and influence home builder overhead costs, which they consider when building project estimates.

Taxes

The combined sales tax rate in Chicago, IL, is just over 10%. Sales tax applies to the construction materials your home builder purchases, so they pay the tax as the consumer. Taxes don’t apply to most construction labor, but your home builder will use the taxes they pay in their estimate calculations and pass the cost on to you.

Permits

You’ll need to make sure you pull the proper building permits for your second-story addition from the City of Chicago Department of Buildings. Your building contractor typically handles this, but the cost of a building permit ranges from $500 to $5,000, depending on the project value and square footage. 

Chicago, IL, enforces energy and building codes strictly, so make sure to leave room in your budget for additional plan reviews and inspections. If you come up against strict laws in your area and your permit is turned down, keep in mind that you may also need to pay for legal assistance. Historic homes, homeowner associations, and areas with strict air rights can be complex to understand without a legally trained eye.

Additional Pros to Consider Hiring 

Building a second-story addition is a big job that requires large crews and specialized professionals. Depending on your project and contract details, the home builder may subcontract other professionals:

• Structural engineers: $120–$250 per hour

• Interior designers: $100–$500 per hour

• HVAC technicians: $50–$150 per hour

• Plumbers: $45–$200 per hour

• Electricians: $45–$95 per hour

Does Adding a Second Story Increase Home Value?

Adding a second story in Chicago, IL, can increase home value, offering a 20% to 50% return on investment (ROI). Many neighborhoods in the city are dense and have limited lot sizes, so expanding upward allows for more living space without sacrificing valuable yard space. Second-story additions tend to offer the best ROI when they expand household capacity with extra bedrooms or bathrooms.

How Angi Gets Its Local Cost Data 

To help homeowners plan their next project, Angi provides readers with carefully researched cost data and upholds strict editorial standards. We start with national average project costs, which we collect by analyzing competitor information, retailer material costs, and input from professional contractors. We then apply local price index data to calculate location-specific estimates that reflect what homeowners typically pay in their local area. To do that, we use data from the U.S. Bureau of Economic Analysis (BEA), including its Regional Price Parities (RPPs), which measure price differences across cities. This helps us account for differences in labor, materials, and overall cost of living, so estimates in higher- or lower-cost areas better reflect real-world local pricing.

Every estimate undergoes a thorough editorial review to verify accuracy, consistency, and alignment with observed market conditions.

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