How much does it cost to add a second story?

Growth is a natural part of life, and it’s very common for individuals and families to outgrow their homes. No matter how much you declutter or reorganize, sometimes you just can’t create any more space. When that time comes, you must either buy a new, larger home, or it’s time to put an addition on your home.

Space is a premium in many places and sometimes it makes more sense to build up rather than build out. The cost to add a second story to your home isn’t cheap, but it’s still likely less expensive than buying a new home outright. If you need more space and aren’t ready to move, here’s what to consider when building a second story in your home.

How much does it cost to add a second story to a home?

As you might expect, the cost to add a second story to a home ranges significantly based on a number of factors. However, it’s never going to be cheap.

The cost to add a second story to a home generally ranges between $100 and $300 per square foot, according to HomeAdvisor. Doing some math, expect to pay $100,000 to $300,000 for a 1,000 square-foot addition. If you’re building on a smaller home, you could do the project for $60,000 to $180,000. 

However, there are myriad factors that impact the potential cost, including where you live. Some areas simply cost more to build than others.

What factors impact how much it costs to add a second story?

There are many small items that could impact how much it costs to add a second story to a home, but let’s touch on some of the biggest cost factors.

Location

Where you live has a large bearing on how much you’ll spend to add a second story. Location can affect:

• Cost of local permits
• Labor and material costs in your area
• HVAC and insulation requirements based on local climate
• Assessment oflocal property taxes based on square footage

Labor

While labor is impacted by the location of your home, it merits its own section here. That’s because not all projects require the same labor.

For instance, while you’ll certainly need a dedicated team of contractors to build the second story, you may also want to hire an architect to design the addition. That will cost an average of $2,000 to $5,000, according to HomeGuide. A general contractor team that will manage the budgeting, hiring, and construction (and sometimes design) will cost between 10% and 20% of the total project cost.

That doesn’t include specialists like plumbers, electricians, carpenters, HVAC specialists, and more that you might need for your project. All told, labor will likely amount for 30% to 60% of the complete project cost.

Shape and size of the story

Of course, the bigger your addition, the more you can expect to pay. As we’ve said before, adding a second story usually costs between $100 to $300 per square foot. The larger the project gets, the more you’ll spend. Likewise, if you’re pursuing any sort of unique shape that doesn’t simply align with the first story, you may have to spend more, too.

Materials

Like any home improvement or renovation project, if you choose higher quality materials, you will pay more. This is an area where you have a significant amount of control on budget, at least. If you’re tight on budget, consider some lower quality or easier to find materials rather than splurging on that rich mahogany.

Foundation inspection

A single-story home was built on a single-story foundation. While some foundations can support another story built on top without making any changes, many can’t. Before you do anything, hire an inspector to verify that your foundation can support another story. Otherwise, you may have to budget another $5,000 to $10,000 to make foundation improvements.

Temporary housing

Adding a second story to your home is a major project. It will turn your home into a construction zone, so if you have kids or pets, it’s not advisable to stay in the house. That means budgeting for a short-term rental or an extended hotel stay for the weeks or months it takes to build the second story.

Type of second story addition

Finally, not all second story additions are created equal. There are three types of second story additions: Full-story, partial, and prefabricated.

Like the name suggests, a full-story addition essentially builds a second story that aligns with the first story, doubling the square footage of your home. A partial addition adds just some extra space, like an additional bedroom and bathroom, that doesn’t cover the entire footprint of the first floor. 

Another option that is becoming more popular is adding a prefabricated room or unit to your home. This is an easy way to add a little square footage to your home in the form of a bedroom, a home office, an in-law suite, a storage room, or whatever else you choose to use it for. This is most commonly done over attached garages. Some people opt to build a separate garage and accessory-dwelling unit (ADU) to add to the livable space on the property rather than adding a second story.

Is it better to add a second story or build out?

The decision to either add a second story or add an addition to the first story of your home depends largely on your home’s footprint.

HomeAdvisor estimates that adding a major addition to your home costs between $21,705 and $69,887. That’s certainly less expensive than most instances of building a second story. However, to do so, you’ll still need to jump through a number of the same hoops, including finding temporary housing and building and incorporating a new foundation. That said, it’s still less expensive and less of a hassle than removing the roof.

If you have the space on your lot to spare, building out is less expensive and less of a hassle than adding a second story to your house. The most cost-effective option to add square footage, however, is likely finishing your basement if you have one. This can cost as little as $6,500 depending on materials and the size of the basement.

One last thing to consider when deciding adding a second story and building an addition is the return on investment (ROI). This Old House estimates a second-story addition comes with a roughly 83% ROI on average when you resell the home, compared to 78% for a family room addition.