How Much Does A Home Addition Cost?

Home Addition by Type of Room

The room type you’re building is one of the first factors in determining your project cost. Rooms with plumbing, such as a kitchen or bathroom, are typically more expensive to add than rooms without, like a primary bedroom or sunroom.

Attic

Converting an attic into a livable space costs about $40,000. This conversion needs to have enough insulation and ventilation for comfortable year-round use. Plus, remember to account for the cost of installing a staircase in this room.

Bathroom

Adding a bathroom costs around $35,000, while adding a more luxurious and larger bathroom of 100 square feet will cost about $90,000. Bathrooms are a more expensive addition because they require plumbing, plus fixtures like showers and toilets.

Bedroom

A primary bedroom addition costs around $62,500, but if you’re planning to add an en suite bathroom, expect to spend up to $100,000.

Dining Room

A standard dining room is about 14-by-16 feet, and this costs about $20,000 to $45,000 to add to your home. Expect to pay more if you plan to add a wet bar or built-in cabinets and shelves.

Kitchen

A kitchen addition costs around $20,000 to $90,000. Kitchens are one of the most expensive home additions because they require electrical work, plumbing, and appliances.

Laundry Room

A laundry room addition costs about $8,070, including the cost of newer appliances, additional storage, and waterproof flooring.

Living Room

You’ll spend about $20,000 to $45,000 for a 12-by-18-foot living or family room. The cost will increase for larger rooms with high-end finishes and custom entertainment centers.

Mudroom and Sunroom

Mudrooms and sunrooms cost around $8,000 to $16,000. These are popular additions for added storage and living space. A 50-square-foot mudroom, including storage and built-in organization systems, costs around $12,000. Expect to spend $8,000 to $11,000 for a simple sunroom or upward of $80,000 for a 200-square-foot space with electrical wiring and heating.

Home Addition by Style 

Home addition add-ons can vary by the style you choose. Balconies and bump-outs are generally more economical options and can sometimes be completed for as little as $5,000 to $10,000. On the more expensive end, an in-law suite can range from $50,000 to over $100,000, and a second-story addition can run between $300 to $500 per square foot. Below is a list of style options to consider.

Balcony

For the cost of a balcony addition, expect to pay roughly $5,000 to $10,000. Adding a balcony is a less expensive alternative to porches or decks if you want more outdoor space.

Bump-Out

A bump-out is an addition to a home's square footage—typically between a few feet and a single room—and a bump-out addition costs about $5,000 to $10,000. This is one of the least expensive home addition options, but it also tends to add the smallest amount of space to a home.

Cantilever

A cantilever costs around $15,000 to $25,000 and is an upper-floor home addition that juts out past the first floor. This style requires additional support beams either angled and attached to the house or anchored into the ground.

Dormer

A dormer addition costs between $5,000 to $10,000 and is a roofed structure that usually includes a window. It’s commonly added to increase a loft or attic's usable space and create window openings in a roof plane.

Garage

Adding a garage costs around $25,000 to $50,000, depending on whether you want an HVAC system and electricity. Adding a garage is ideal if you want covered shelter for your car, a space for handy work, or additional storage.

In-Law Suite

An in-law suite is a small studio or apartment that adds separate living quarters to your property. In-law suite additions cost around $50,000 to over $100,000. 

Modular Room

Modular or prefabricated rooms will generally cost between $20,000 and $30,000, or around $25 per square foot. This is a less expensive option for a home addition because it's manufactured and delivered to your property, but it often has fewer customization options. Speak with a pro before adding a room to a modular home, as it may not be equipped to support an addition.

Porch

Building a porch costs between $5,000 and $25,000. A new porch can add extra square footage to your home while also offering space to take a breath of fresh air.

Second-Story Addition

A second-story addition costs upward of $500 per square foot and is one of the most expensive addition types because it requires removing and replacing the existing roof.

Home Addition by Size

Most home additions cost about $80 to $200 per square foot, including materials and labor. The cost is likely to be much higher for a second-story addition, at around $300 to $500 per square foot.

Home Addition by Material 

Material prices fluctuate vastly based on the design type and style you choose. A reasonable estimate will include all interior materials (like floors and paint), plus exterior materials (such as roofing and siding) to match the addition to the rest of the home.

Home Addition by Labor

Successful home additions require skilled laborers. Your project may require design services, an electrician near you, a local plumber, plus contractors for demolition and construction. It’s wise to reserve 30% to 50% of your overall project budget for installation costs. Here’s a list of pros to consider for your home addition project.

General Contractor 

General contractors oversee and manage the full scope of a project, typically after the designs have been drawn up and agreed upon. General contractors charge about 10% to 20% of your total construction project cost, also called "cost plus." For larger projects, you might pay closer to 25% for their services. They typically don't charge an hourly rate.

Architect

A local architect can help ensure that your home addition matches seamlessly with the rest of your house. It’s usually not required to hire an architect for a home addition. However, these services can help the addition look and function its best and save you headaches and costs down the line. Architect fees typically fall 5% to 20% of the total project cost. 

Excavation and Demolition Pro

To prepare the site for the new addition, there will need to be demolition and land excavation costs. Excavation alone will cost about $1,500 to $5,800, although these prices can be closer to $10,000 for bigger projects, like adding a second floor, installing a basement, or converting an attic.

• Permits: Even a small 2-feet bump-out requires a permit from your city and will cost about $400–$2,000.

• Cleanup: Construction cleanup costs around $470 and gets broken into two types: rough cleaning and final cleaning. Most general contractors will handle the rough cleanup, but you'll want to do a final, thorough cleaning. Many factors contribute to the final cost of any post-construction cleanup job, including:

• Addition size: Larger projects command a higher overall price but usually at a lower per square foot rate.

• Local competition: If you live in an area with several construction cleanup contractors available, you can get a more competitive price.

• Supplies and equipment needed (for DIY solutions): If you’re tackling this job yourself, you’ll need to supply all the cleaning tools and equipment for dumping. 

Home Addition by Geographic Location

Depending on where you live, construction costs can vary drastically from one location to another. Similar to how home prices with the same square footage can fluctuate remarkably between markets, so can the cost of an addition. Also, consider the regional labor cost and the state of the construction market when budgeting for your project.

Benefits of Building a Home Addition 

Adding more space by building a home addition comes with many great benefits, including increased space, increasing your home value, and the potential for a better quality of life. Below, we explore the benefits of building a home addition. 

More space: An addition is an excellent option when you're starting to feel cramped in your home. Adding another bedroom, storage space, or recreation room can help tailor your house to your current needs and lifestyle. 

Added property value: Investing in a home addition can give you more space, but it may also increase your home value if you decide to sell.

• Bathroom: 53% return on investment (ROI)

• Primary bedroom and bathroom: 63% ROI

• Sunroom: 49% ROI

• Two-story addition: 65% ROI

No need to move: Just because your family grows or needs more room doesn't mean you're ready to leave your house or neighborhood behind. An addition might offer you a way to stay where you're at without sacrificing space. 

More luxury: Growing your current home might be your best bet for finally getting that new gourmet kitchen, home office, or first-floor primary bedroom. Customizing the space you're already in could accommodate your unique hobbies and activities. 

Building a Home Addition on a Budget 

Home additions can quickly grow in price and, in most cases, everything won’t go exactly as planned. It's important to set aside a percentage of your overall budget (2% to 20%) for contingency funds if any unforeseen costs present themselves during the construction. 

Here are a few tips for keeping prices down:

• Keep things simple. 

• Get several bids from various contractors to make sure you’re getting the right person for the job. The least expensive contractor isn't always your best option and doesn’t always save you money in the long run, so getting references can ensure you’re getting a quality pro.

• Consider premade standalone options instead of customized versions to keep your overall budget down. 

• Check for tax credits or refunds. Home additions are considered capital improvements, and local governments and utility companies often offer rebates for energy-efficient purchases.

• Be flexible. Remodels, renovations, or home additions almost always have a hiccup or two along the way. A willingness to adapt and modify as you go might keep you from completely blowing your budget. 

DIY vs. Hiring a Home Addition Pro

Building a home addition isn't recommended as a DIY project, as this process involves demolition, construction, electrical work, and possibly plumbing, all dangerous and technical jobs. You could also make costly mistakes if you don't correctly lay the foundation or build the support beams. If you're skilled at tasks like painting or flooring, you could save money by doing those tasks yourself. 

Hiring a local general contractor with home addition experience may be the wisest move you can make since they’ll take the burden off and get you the best result. The general contractor will handle hiring and working with all the other pros as part of their service.