How Much Does It Cost To Add A Second Story In 2024? (2024)

Always begin by investigating whether a second story is right for your house. Not all structures can withstand the weight of a second story without additional support. You will need to hire a structural engineer to inspect your foundation.

Permits, the local cost of materials and site preparation also all add to your price tag. On average, labor, materials and related costs come out to the following price ranges.

In order to add a new story to your home, you’ll need to remove the roof above it. While you may be able to keep part of the roof intact and add to the top of the new story, your team may need to replace the roof from scratch. Overall, the more roof that needs to go, the higher the price to add a second story.

Full Addition

Adding a full second-story addition costs between $100,000 and $600,000 depending on the size of your home. Removing the entirety of the roof is complex and you will likely need to fortify or repair your foundation to handle the extra weight.

Partial Addition

Partial second stories only sit on one portion of the house, leaving space for existing chimneys, vents and roofing. You’ll pay between $100,000 and $250,000 on average, though the price heavily depends on size and which rooms are going upstairs.

Room Addition

The average cost to add one room on the second story of your home is $65,000. While you will still need to add steps and alter the roof, the majority of your home’s structure remains the same. Yet again, the type of room and design choices you choose can sway this cost.

Home additions cost an average of $100 to $300 per square foot when you add a second story. As we noted above, the costs depend on the size of the space and which features are already included in the build.

On average, the cost to add a second story ranges from $100 to $300 per square foot. If your one-story house is 1,500 square feet and you’re looking to double that, you’ll pay between $150,000 and $450,000 for a full addition. Partial additions—such as an extra bedroom and ensuite bathroom—could range around 500 square feet, costing $50,000 to $150,000 on average.

All homes are unique, especially when you begin adding customized additions. Consider these factors to determine your home’s second-story price tag.

Location

Where you live has several hands in determining your home addition budget. Prices can vary due to:

• The cost of local permits
• Labor and material costs in your area
• The local climate and how it affects HVAC and insulation requirements
• The style of local homes
• The increase of local property taxes by adding more square footage

Labor

You’ll need a dedicated team of contractors to make your second-story build a success. A general contractor—the pro that often oversees the design, budgeting and hiring for the project—typically charges between 10% and 20% of the total project cost.

Additional labor costs for adding a second story are similar to the price of building a house. Labor will account for between 30% and 60% of the price, covering plumbers, electricians, carpenters, HVAC specialists and all the specialized pros for your project.

Materials

The other half to two-thirds of the costs go toward materials. Some of the most important materials and their average costs—not including labor—for a second story include:

• Lumber: $33,000
• Rough-In Plumbing: $5,700
• Insulation: $4.10 per square foot
• Roofing: $7 per square foot
• Siding: $5.50 per square foot
• Flooring: $6 per square foot
• Electrical wiring: $0.70 per square foot

Building Up vs. Building Out

There is a lot of debate about whether it is cheaper to build up or build out. If your foundation is solid enough to bear the weight of a second floor, building up will cost less in most cases.

Not having to pay for new foundation installation, ground leveling and utility adjustments will often cost less than changing the structure of your existing home. However, this highly depends on your design. In some cases, tearing off the roof and building up requires more costly changes than building on open land.

Permits

There is no question that you will need building permits to add a second story to your home. Budget an extra $1,000 to $2,000 depending on the extent of the build and your local laws.

Site Preparation and Demolition

Demolition will account for the first major phase of adding a second story to your home. The roof, attic and ceiling need to come off, adding to the hourly total of work by your crew. In some cases, the team will use a crane to disconnect the roof, or part of the roof, in one piece for later.

Expanding beyond the basic second-story price breakdown, let’s take a look at the more dynamic cost factors.

Project Size and Scope

As we mentioned above, full versus partial second-story additions alter the price significantly. At an average of $200 per square foot, often the larger the second story, the higher the price. The scope, however, can expand depending on the rooms you place on the second floor and features on the roof such as a chimney, vents or dormer windows.

For example, the cost to add a bathroom to your home averages $90,000 depending on its size and existing plumbing hookups. Kitchen installation and remodels cost an average of $150 per square foot, which accounts for water-resistant finishes, countertops and appliances.

Finishes Used

The finishes chosen for your project provide some of the most flexibility. Prices will be higher if you install hardwood floors over DIYable engineered wood planks. Finishes also widely vary in kitchens and bathrooms based on the type of tile, vanities and countertop materials chosen.

Foundation Quality

Reinforcing the foundation to handle the addition’s weight adds an average of $5,000 to the total cost. Installing a new support beam costs an average of $3,000, though fluctuates depending on its material and how much weight it holds.

Temporary Housing

You’ll rarely be able to live in your home as the team adds a second story. It’s important to account for the average of two to six months of temporary housing. Prices vastly depend on where you live and the size of the rental you need, but be sure to include moving costs for basic amenities.

The construction stages of building a second story are not DIYable, practically or often legally. But it doesn’t mean that you can’t have a hands-on approach to the process. Work with your architect and general contractor to match your vision with your budget.

You can also step in when it comes time to paint the new exterior of your house, hook up basic appliances or install click-and-lock flooring.

Taking on as many DIY tasks as safely possible will cut out the 50% fee for installation. Though as we mentioned above, this is only appropriate for tasks that do not require a permit. Additional ways to cut costs on a second story include:

• Working with standard floor plans and designs provided by your architect or general contractor
• Considering the cost of a floor plan designer to choose the best plan for your budget
• Speaking with at least three general contractors for estimates before choosing
• Scheduling your build far in advance to prepare and wait for deals on materials
• Opting for budget-friendly finishes, fixtures and roofing options
• Handling the cleanup and junk hauling by yourself

To arrive at the average costs in this article, editorial team members surveyed nine cost databases on national and local levels. All averaged figures were correct at the time of publication and may be subject to change.