How Much Does It Cost to Add a Second Story? (2024 Guide)
Hello, my friend, hello again; today we come together to talk about How Much Does It Cost to Add a Second Story? (2024 Guide) and hope the blog can help you.
The cost to add a second story ranges from $100,000 to $250,000, though many homeowners spend about $175,000 to gain some much-needed extra living space.
Highlights
- The cost to add a second story is about $175,000, but a typical average is $100,000 to $250,000.
- The size of the addition and the home are the biggest cost factors, but homeowners will also need to consider the cost of adding plumbing, electrical lines, HVAC, and any foundation structural work.
- Adding a second story gives homeowners more living space without sacrificing existing outdoor living space, and it also increases the home’s value.
- Any major construction project that alters the home’s design is a job that’s best left to general contractors and licensed professionals who have the experience, equipment, and time to complete the job to code.
Thinking about adding a second story to your home?
Talk to top-rated local experts to know what you can do with your budget.
Homeowners can choose from a number of home projects to improve the look and functionality of the house. Sometimes the house simply does not have enough space, so homeowners can opt to install an addition or second story. Generally, an addition will be added to the exterior of the home on the ground floor. However, single-level homes may be able to increase the living area by adding a second story.
According to Angi, the cost to add a second story to an existing house is about $175,000 on average, though the cost can range from $100,000 to $250,000, depending on the size of the addition, current home size, and many other cost factors. Given the financial investment required for this project, it’s a good idea for homeowners to find out more about the project scope and cost considerations.
Key Cost Factors
Building a second-story addition is a complicated project that involves a wide variety of elements, such as framing, plumbing, electrical work, HVAC installation, drywall, floor installation, and more. The project complexity means that the cost to add a second story can vary greatly depending on the size of the addition, the existing layout of the home, and the local labor rates. Keeping these cost factors in mind can help homeowners create an accurate budget for this job.
Thinking about adding a second story to your home?
Talk to top-rated local experts to know what you can do with your budget.
Addition Size
The size of the addition has the greatest impact on the cost to add a second story. Contractors will estimate costs for the amount of material required, the weight of the addition and other structural needs, labor, and any additional permitting. Homeowners will want to know the estimated size of the second-story addition they need. For instance, the cost to add a room to a house will be less than the cost to add a full second story, since additional structural support, HVAC, plumbing, and electrical systems will be needed beyond the basic construction materials.
The second-story addition cost per square foot works out to about $100 to $500 on average. The larger the second-story addition, the more material and time it will require to complete the upgrade. Since larger additions will take longer to complete, homeowners can expect higher labor costs for extensive jobs. Before starting this project, homeowners are advised to work with the contractor to come up with a basic plan and cost estimate to minimize unexpected costs.
| Size of Addition | Average Cost (Materials and Labor) |
| 250 square feet | $25,000 to $125,000 |
| 500 square feet | $50,000 to $250,000 |
| 750 square feet | $75,000 to $375,000 |
| 1,000 square feet | $100,000 to $500,000 |
Home Size and Shape
The square footage of the second-story addition is one cost consideration, but the homeowner also needs to keep in mind the size and shape of the existing home. It’s common to install a second story that matches or complements the existing layout of the home, which could lead to higher costs on large homes.
Also, if the existing layout of the home can’t accommodate the installation of the preferred second-story floor plans, then the contractor may need to make updates to the house, which can increase the overall cost of the job. In this case, homeowners are advised to work with a structural engineer and a contractor to determine the best possible layout for the second-story addition to ensure the occupants’ safety.
Plumbing and Electrical Work
Adding a second story to the home helps to increase the available living area, but the contractor will need to add appropriate plumbing and electrical lines to ensure that the new addition is both comfortable and functional. Typically, a general contractor will subcontract with a professional plumber and electrician to handle this work. Homeowners can review how much a plumber costs and how much an electrician costs as part of the budget planning process.
Plumbing tasks include running new water lines, drain lines, and vent pipes as well as installing any water-using appliances or fixtures. Adding plumbing will generally cost about $4.50 per square foot. An electrician will run new wires for the space and install suitable electrical outlets, lights, and any other electrical components that are required. These tasks cost about $6 to $8 per linear foot.
HVAC Installation
Second-story additions are usually ideal for creating extra bedrooms and living areas, but these areas also need climate control for comfort. For this reason, an HVAC professional is needed to install new ductwork so that the second floor of the home can be properly heated and cooled.
HVAC installation ranges in cost from about $40 to $65 per linear foot. Generally this work is handled by a licensed HVAC technician, just as a licensed plumber and electrician are brought in to handle plumbing and electrical work. Some home builders may have one or more individuals on staff who have an HVAC license, so it’s worth asking who will be doing this work.
Depending on the existing HVAC unit and the size of the home addition, a new HVAC unit might be needed to accommodate the additional square footage. On average, HVAC unit replacement cost is $7,500, though this will vary from one geographic area to another.
Interior Finishes
Beyond the plumbing, electrical, and HVAC work, the contractors will also need to complete a wide variety of interior finishes, from drywall to door installation. The cost for this part of the project can vary significantly depending on the size of the addition, the layout, and the second-story design.
Larger additions will generally be more expensive, since they require more materials like flooring, insulation, and drywall. The number of windows to be installed will also greatly affect the cost, since double-pane window costs can be significant. The same holds true for doors, which can range greatly in style and cost.
| Type of Interior Finish | Average Cost (Materials and Labor) |
| Door installation | $40 to $500 per door |
| Drywall | $0.40 to $0.65 per square foot |
| Flooring | $0.50 to $15 per square foot |
| Framing | $3 to $6 per square foot |
| Insulation installation | $0.50 to $5 per square foot |
| Interior painting | $1 to $3 per square foot |
| Light installation | $70 to $300 per fixture |
| Window installation | $150 to $650 per window |
Exterior Finishes
The exterior finishes are just as important as the interior finishes, if not more so, since the exterior of the home protects everything from electrical wires to insulation and wood framework. Depending on the design, the contractor may need to hire a mason to install new brickwork or work with a siding contractor to put in new cedar or vinyl siding.
The second story will also require new gutters and a new roof to ensure that rain, snow, and ice drain properly away from the home. It might be a good idea to have the contractor touch up the paint on the existing window trim, door trim, and gutter system to avoid a distinct difference between the old and new parts of the home. Alternatively, homeowners could ask about house painting costs if it’s time to refresh the entire look.
| Type of Exterior Finish | Average Cost (Materials and Labor) |
| Exterior painting | $1 to $4 per square foot |
| Gutter installation | $5 to $15 per linear foot |
| Roofing | $3 to $6 per square foot |
| Siding | $4 to $13 per square foot |
Labor and Permits
Labor rates vary based on the profession and location, so while the general contractor may charge 10 percent to 25 percent of the total project cost, an electrician may charge only about $50 to $100 per hour. The overall cost of the job can range significantly based on the type and amount of labor required, so it’s a good idea to have a basic understanding of local labor rates.
The addition of a second story means homeowners will need to acquire a building permit and submit building plans. Permit acquisition is generally handled by the contractor, but homeowners can ask the contractor to ensure that’s the case. Building permits for this type of work typically range from about $1,200 to $2,000, depending on the location and scope of work.
| Type of Contractor | Average Labor Rate (per Hour) |
| Architect | $125 to $250 |
| Carpenter | $75 to $100 |
| Draftsperson | $50 to $130 |
| Electrician | $50 to $100 |
| HVAC technician | $50 to $100 |
| Interior designer | $50 to $200 |
| Plumber | $45 to $200 |
| Structural engineer | $100 to $200 |
Geographic Location
The location of the home can impact the cost of materials and labor, so it’s recommended that homeowners get estimates from several reputable companies in the area to better understand the local average cost of adding a second story. Homeowners with properties that are located in major urban centers will typically pay higher rates for both materials and labor.
Rural locations generally have lower costs associated with this type of project since local supply and demand are lower than in densely populated cities. Additionally, if the home is located in an area that experiences severe winter weather, then the materials required to build the home may cost more than what’s needed to build a home in a more temperate area.
Additional Costs and Considerations
Beyond the upfront cost, there are several additional costs that may be required to complete this project. Whether these extra costs are necessary depends on the property. Homeowners will need to consider these potential cost factors when planning the project and work with a structural engineer or contractor to determine if they are relevant to their project.
Foundation Reinforcement
Many single-story homes do not have a foundation that is designed to support the weight of a second-story addition. Before homeowners add a second story to the home, it’s necessary to have the foundation assessed by a structural engineer. Their expertise will evaluate whether the home can support a second story or if it will need to be reinforced before proceeding.
Foundation support work will increase the time it takes to complete this job, but it’s essential to have a strong foundation for the home to avoid the risk of collapse. This extra work will typically cost at least $5,000, though the cost may increase based on where the home is located, the scope of work, and the condition of the existing foundation.
Demolition Work
A second story can’t be constructed on top of an existing roof, so the contractors will need to demolish and remove a portion of the current roof before they can build and attach the new second story to the home. Additionally, the contractor may need to open up the walls and ceilings or even remove part of a room to make space for a new staircase and ductwork.
Removing a roof will cost about $1,250, while replacing the roof once the job is complete can cost about $4.35 to $11 per square foot. If the home has an existing chimney, the contractor may be able to work around it, or they may need to remove it for an average cost of $4,500.
Staircase Construction
Generally, the added second story will need a new staircase for the homeowners to access it. Installing a new staircase for the home can range in cost from about $1,000 to $5,000, including materials and labor. The placement of the staircase should be discussed with the structural engineer and the contractor to determine the best position based on the existing layout and the layout of the new second story. However, it’s important to keep in mind that the cost of this job can increase depending on the complexity of the layout, space available, and custom additions like premium hardwood or carpeting.
Landscaping
Installing a second story is a big project that often involves the use of heavy construction equipment, which can damage the lawn, garden, and nearby plants. Once the job is complete, the house may look great, but the yard could need some attention. Homeowners may want to hire one of the best landscaping companies to restore or improve the appearance of the yard.
Professional landscaping costs about $4.50 to $12 per square foot, though the exact cost depends on the work required to restore or update the look of the yard. It’s worth discussing landscaping services with the primary building contractor to determine if they offer landscaping services or have a reliable company that they often work with for this type of job.
Temporary Housing Costs
In most cases, it isn’t safe to stay in the house during the construction of a second-story addition, so the home’s occupants will need to find a place to stay until the job is completed. Temporary housing costs range based on geographic location and the type of temporary housing.
Short-term rentals can be a good option, though some people may choose an extended stay at a motel or hotel. Another option is to purchase or rent a mobile home, RV, or trailer for the duration of the project.
Thinking about adding a second story to your home?
Talk to top-rated local experts to know what you can do with your budget.
Types of Second-Story Additions
If budget is a major consideration but extra space is needed, homeowners can decide from among other second-story addition options. Some popular choices include a garage bonus room, a bump-out addition, a full second-story addition, a partial second-story addition, and a second-story balcony.
| Type of Second-Story Addition | Average Cost (Materials and Labor) |
| Bump-out addition | $4,000 to $30,000 |
| Full second-story addition | $100,000 to $600,000 |
| Garage bonus room | $60,000 to $120,000 |
| Partial second-story addition | $80,000 to $300,000 |
| Second-story balcony | $30 to $60 per square foot |
Bump-Out Addition
Extending the home into the yard to add an extra room is one way of increasing the available living space, but if the property has a partial second story, the homeowner may be able to add a bump-out addition to the second floor instead of the ground floor. This is helpful if there isn’t enough space on a property to expand the home’s footprint.
Adding a bump-out is how a contractor creates an extra room on the second floor by building on top of only a portion of the first floor. This project is one of the more affordable ways to add a second story to a house, ranging from just $4,000 to $30,000 in cost.
Full Second-Story Addition