Home Addition Cost in New York City [2025 Data]

Space is at a premium, and the cost of living is high in New York City, so homeowners looking to build a home addition will need to budget appropriately for this project. The average cost of a home addition in New York City is $69,773, with most homeowners paying between $26,333 and $113,450. The size and type of addition will be the major determining factors in how much you’ll pay, with materials, labor costs, and permit fees also contributing to the total project cost. 

Home Addition Cost Factors 

The cost to build an addition in New York City is based on factors including the addition size, how the space will be used, whether the addition is building up to another story or out as a bump-out addition, labor costs, and more. We break down some of the key factors that determine how much you’ll pay for a home addition in New York City.

Size

Home additions cost between $80 and $300 per square foot if you’re building out and between $400 and $700 per square foot if you’re building up. The cost to add a 10x10 room to a house costs an average of about $20,000 if you build out and $55,000 if you build up. The size of your home addition can also affect how long the addition takes to build, which can increase your labor costs over the course of the project.

Where in those ranges your total falls also depends on the complexity of the room and its finishes. For example, adding a bathroom will often cost more than a bedroom since it requires additional plumbing and electrical work.

Materials

As you can imagine, it takes many kinds of building materials to complete a custom home addition. Material prices vary widely, so your price could push closer to $113,450 if you choose luxury or high-end materials at each step of the way.

Framing Materials Cost:

Insulation Materials Cost:

Roofing Materials Cost:

Flooring Materials Cost:

Siding Materials Cost

Type

The cost to add on a room varies based on the size and type of home addition you’re building. Rooms like kitchens and bathrooms require plumbing work that a bedroom doesn’t, while an unfinished attic home addition may not require electrical or HVAC work that a bedroom needs. The cost per square foot for your home addition will vary based on utilities and the finishes required for how you plan on using the extra square footage.

Site Prep

On average, site prep for a home addition costs between $1,500 and $5,000. You may not need any site prep in some cases, while other home addition projects may require grading land, demolishing concrete patios, removing trees, and other work that can add to your total.

Permits

Building an addition to your New York City home requires a permit from the NYC Department of Buildings. Permit fees are based on the total cost of the project and the square footage. You’ll pay $0.25 per square foot for the first $100,000 of the project, then $0.20 per square foot after that for projects with a cost of up to $1 million. 

In most cases, a New York state-licensed Professional Engineer (PE) or Registered Architect (RA) will need to file the plans and pull the permits. Confirm that all permits to build an addition have been obtained and you’ve paid all applicable fees before work begins. 

Home Addition Pro Costs

Home Builder Pro Costs

Hiring a general contractor or homebuilder in New York City to build your addition will cost 10% to 20% of your total project cost. A qualified homebuilder will coordinate your project, from bringing on subcontractors to answering your home addition questions and keeping the project on schedule and within budget. 

Additional Pros to Consider Hiring

Building an addition requires the skills of the same professionals it takes to build a house, just on a smaller scale. You’ll need to hire a structural engineer to ensure the build is structurally sound, and pros like electricians, plumbers, and HVAC techs to run utilities to the new space. Finish carpenters, drywall installers, and interior painters will help finish your addition and get it ready to use. Here are some of the pros to consider hiring and how much they may cost: 

• Interior painter cost: $2–$6 per sq. ft.

• Roofer cost: $4–$11 per sq. ft.

• Electrician cost: $50–$100 per hour

• HVAC technician cost: $100–$250 per hour

• Plumber cost: $45–$200 per hour

• Carpenter cost: $75–$125 per hour

• Structural engineer cost: $200–$1,500

• Landscaper cost: $1,200–$6,200

Does a Home Addition Increase Property Value?

Building a home addition can add value to your property, with an average return on investment (ROI) of 20% to 50%, depending on the type and size of the addition. In New York City, the additions with the highest ROI include additional bathrooms and expanded kitchens, since space is at a premium in the city and additional space for these rooms is highly desired. Adding on to your NYC home can allow you to ask a higher price when it comes time to sell, and make your home more appealing to prospective buyers. 

How Angi Gets Its Cost Data

Home is the most important place on earth, which is why Angi has helped more than 150 million homeowners transform their houses into homes they adore. To help homeowners with their next project, Angi provides readers with the most accurate cost data and upholds strict editorial standards. We survey real Angi customers about their project costs to develop the pricing data you see, so you can make the best decisions for you and your home. We pair this data with research from reputable sources, including the U.S. Bureau of Labor Statistics, academic journals, market studies, and interviews with industry experts—all to ensure our prices reflect real-world projects. 

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