The Cost To Add A Second Story To A House And What To Expect

Emma Tomsich

7 - Minute Read

UPDATED: Dec 16, 2023

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Homeowners who live in a single-story house may consider adding a second floor to increase the size of their home. Adding another floor is a practical option for many reasons, from accommodating a growing family to increasing home value to wanting more living space.

But doubling the size of your home’s square footage with a second-story addition is a bigger investment and challenge than many people might realize. A second-story addition is a huge project. You should understand the process and its costs before remodeling or moving to get a place that meets your newfound need for more space.

Let’s take a deeper look at the realities of adding a second story to your home and its potential impact on your life and finances.

Can You Add A Second Story To A House?

In short: Yes, you can usually add a second story to a house. But before you start making plans for your new second-story addition, you must take many factors into account. Not every house can support a vertical expansion. To confirm that you can add a second story to your house, you’ll need a permit approving the build.

You also need a clear understanding of pricing before starting the remodel and any potential limitations or obstacles that may crop up.

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How Much Does It Cost To Add A Second Story?

First things first: Figure out how much the project will cost before committing to anything.

The average cost of adding a second story to a house ranges from $80,000 – $600,000, or $100 – $500 per square foot, according to HomeAdvisor.

The final cost of renovating will depend on several factors associated with the addition.

Types Of Second-Story Additions

As you research and plan your second-story addition, you may have various options to explore to renovate your space. Your best option will depend on your budget. And you’ll need to keep the home’s resale value in mind.

Here are a few second-story builds to consider:

Full Addition

A full addition installs a complete second floor on the home. The entire roof is removed and replaced, and the floor is built over the home’s total square footage. Full additions are usually better for smaller homes. The average cost of adding an entire new floor to your home ranges from $100,000 – $600,000 or more.

Partial Addition

A partial addition usually costs less and builds a smaller second floor on a portion of the home. The average cost of adding a partial second-story addition ranges from $80,000 – $250,000.

Bonus Room

A bonus room – which usually doesn’t feature a bathroom – can be anything from a playroom to a home office. And it’s a more affordable option than a full or partial addition. The average cost of adding a bonus room as a second-story addition is $50,000 or more.

Second-Story Addition Cost Factors

An inspection must be completed on the home’s foundation to ensure it can hold the extra weight of a second floor.

Certain types of soil can only support a specific weight load. You don’t want to overburden the ground and risk damaging your house or creating unsafe conditions. Any contractor will make sure this is the first step of the project. A structural engineer will inspect the home for foundation issues and make recommendations. Most required foundation work for additions costs $9,100 on average.

Here are other expenses to factor into your remodel:

Size

The size of your home will impact the overall cost of adding a second story. More square footage to cover means more materials and labor. It will likely cost more to add a full second-story addition to a 2,500-square-foot, single-story home than a home that’s 1,000 square feet.

Unique home shapes and features will also increase the cost of adding a second story because these features can complicate the work.

Location

The state or city you’re in will also influence the overall cost of your second-story addition. Environmental factors may require additional features like heat or air conditioning. The cost of permits will vary depending on where you live, including the cost and availability of local contractors.

A contractor in a busy metropolitan area may be easier to find but will likely cost more to hire than contractors in rural areas.

Labor

You’ll likely need the help of a few professionals to ensure the project’s safety and draft its style. Depending on your plans for the space, you may need to hire a structural engineer, a general contractor, an architect and an interior designer. The cost of these professionals will vary based on where you live, but on average, they can cost up to $500 an hour.

Materials

Materials are typically around half of a project’s total cost. The materials and quantities you need will depend on the size of your addition and how you plan on using the space.

For example, you may need to install plumbing if you’re including a kitchen or bathroom. If you’re redoing the roof, you’ll need to purchase roofing materials.

The quality of the finish on your materials also contributes to the project’s overall cost. For example, subway tile may cost less than marble, and laminate floors may be less expensive than white oak flooring.

Permits

The cost of building permits for your second-story addition will depend on where you live and typically range from $460 to $2,773. Your general contractor can help you obtain the necessary permits for your remodel.

Demolition

Demolition also contributes to the overall cost of adding a second story. Depending on the scope of your remodel, demolition can have a small or large impact on your overall budget.

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Adding A Second Story To A House Yourself Vs. Hiring A Contractor

You can cut the cost of many renovations and remodeling projects by taking the DIY route and completing them yourself. However, based on the difficulty and length of adding a second story to a house, building code requirements and other considerations, we recommend hiring a professional to handle your addition.

While you might prefer to avoid the cost of hiring a contractor, they have experience keeping projects on track, on budget, and most importantly, safe.

The Cost Of Building Up Vs. Building Out

As you begin planning your home renovation, compare the cost of adding a second story to expanding your first story. There are many benefits to building out instead of up. In most cases, building out can be significantly less expensive than building up. But you can only build out if there is enough land available.

Many homeowners pay additional expenses when adding a second story to their homes, including the addition of a staircase, structural supports and footings, building permits, repairs to the first floor, architectural and structural engineering, plumbing, a new HVAC system, removal and storage of personal items during the renovation and cost of rent or a hotel during the construction of the second floor.

You can save money on these expenses by building out or renovating your lower level or basement. After adding up all their expenses, the most cost-effective option for some homeowners is to sell their homes and purchase a home with a second story.

How To Reduce Your Second-Story Addition Costs

Luckily, there are a few ways to reduce the cost of a second-story addition:

  • Design a simple layout with your architect
  • Choose inexpensive materials and furnishings
  • DIY painting inside and outside the home or laying down flooring
  • Opt for a partial addition so you can stay in your home or move in sooner
  • Find a friend or family member to stay with during renovations

You also don’t have to take on the entire expense of the addition at once. You can make an initial investment in the basic structure of the second floor and the roof, ensuring that you can continue to live on the first floor. You can also stretch out the finishes to each room on the second floor according to your budget and timeline.

FAQs On Second-Story Home Additions

Review these important questions to ask yourself and your contractor before beginning a second-story addition:

Why does it cost more to build a second story than a first story?

It can cost more to build a second-story addition because it typically requires the complete removal and replacement of a home’s existing roof. Depending on the condition of your existing roof, you may be able to lift it off in one or two sections with a crane and reinstall it on top of the new addition.

Additionally, more support structures may need to be installed to ensure the second story is stable and connected to the first floor. And if you relocate during the build, you’ll be spending money to stay at a hotel or a rental.

Can I live in my house while adding a second story?

You can sometimes stay in your home during the construction of a second-story addition. However, we’d recommend that you live somewhere else during the build to ensure your safety and timely completion of the project.

Finding a temporary living space allows builders to keep the project on schedule and will protect you and your family from the dust and the potential dangers of construction.

How long does it take to build a second story?

Many factors influence the time it takes to complete a second-story build, including weather conditions and the availability of materials. On average, a second-story addition should take 6 – 12 months to complete. A partial addition will likely take 3 – 5 months.

How do I know if I can add a second story within my zoning district?

Visit your local government zoning office to confirm whether you can add a second story to your home. Many zoning districts have limits for the height of structures. If other houses in your area have second stories, use them as a benchmark for how high you can build, but it’s best to check with an official agency before beginning your project.

How do I find a good contractor?

Make sure your contractor is licensed and certified before you hire them. A good contractor will discuss the project with you in detail, making sure to gain a clear understanding of your needs and expectations. They should also be upfront about pricing and not tack on hidden costs.

The Bottom Line: A Second-Story Addition Can Expand Your Home

At the end of the day, building a second story will depend on your budget. Consider less expensive home addition options and ways to save on your second-story addition to keep your expansion within your budget. You’ll increase the space in your home, and done right, your home’s value.

If you’re ready to finance this or any home improvement project, apply for a cash-out refinance today.

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Emma Tomsich

Emma Tomsich is a student at Marquette University studying Corporate Communications, Marketing and Public Relations. She has a passion for writing, and hopes to one day own her own business. In her free time, Emma likes to travel, shop, run and drink coffee.