Addition cost guide
What does a home addition cost in Suffolk County?
Typical price ranges for first-floor, full, and second-story additions — and the factors that move your number. These are planning ranges, not quotes; your real price comes from an on-site estimate.
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Typical cost ranges by addition type
Ranges are typical for Suffolk County and for planning only. Your estimate depends on your home and the scope you choose.
First-floor bump-out / rear addition
Lower end of the addition range
No stairs. Great for a bigger kitchen or family room. Foundation and roof tie-ins drive cost.
Full two-story addition
Higher end of the addition range
Maximum space — a whole new wing. Foundation, structure, stairs, and two floors of finish.
Second-story addition
Highest end — new structure underneath
Building a new second floor on a one-story home. Major structural work before any finish.
These are not quotes. Cost depends on your home's structure, your lot, your town's zoning, and the finishes you choose. Get a free on-site estimate for a number tied to your house.
What drives the price?
- Total square footage added
- Foundation work and any new structural walls
- Plumbing and electrical — kitchens and baths add the most
- Permitting and zoning for your Suffolk County town
- Interior and exterior finishes — roofing, siding, flooring, windows
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Cost questions homeowners ask before calling.
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