Second-story addition cost calculator
Price your second floor with Southeast Michigan numbers
Move the slider, pick a finish level and count the bathrooms. The range updates as you go and uses the same $260 to $400 per square foot band we quote from.
Planning range
$220,000 to $273,000
About $275 to $341 per square foot, all in
Includes engineering, permits, tear-off, reinforcement, framing, roof, mechanicals, stairs and finishes. Excludes your relocation, furniture and anything found once the roof comes off.
Get a fixed-price proposalWhat a second-story addition costs in Southeast Michigan
A second-story addition in Southeast Michigan runs $260 to $400 per square foot. That puts a 600-square-foot addition at $156,000 to $240,000. A full second floor over a 1,200-square-foot ranch lands at $312,000 to $480,000. Going up costs more per foot than building out, because you’re paying for a roof tear-off and structural work before a single new room exists.
Those numbers aren’t pulled from a national database. They’re the ranges Wright’s prices second floors from in Southeast Michigan, and they match our Michigan second-story guide. The calculator above uses the same band, so the number you see there is the number we’d start a conversation with.
Real second-story proposals from 2026
Here’s what five second-story proposals Wright’s sent this year actually came to. Names and addresses stay private. The totals are the real figures from those proposals, before any client changes.
| Scope | Proposal total |
|---|---|
| Second-story addition | $183,517 |
| Second-story addition plus a remodel | $254,082 |
| Second-story addition | $255,960 |
| Second-floor addition | $262,058 |
| Second-story addition | $290,428 |
Notice the floor. Not one of them came in under $180,000. If your budget is closer to $100,000, a second story probably isn’t the right tool, and a dormer addition, a loft conversion or a bump-out will get you more room for the money. We’d rather tell you that on the first call than in the proposal.
Second-story addition cost per square foot, by finish level
Finish level moves the number more than anything except structure. The structural work, the tear-off and the new roof cost about the same whether the bedrooms get carpet or white oak. What changes is everything you touch once you’re upstairs.
| Finish level | Cost per sq. ft. | 600 sq. ft. | 1,000 sq. ft. |
|---|---|---|---|
| Standard | $260 to $310 | $156,000 to $186,000 | $260,000 to $310,000 |
| Upgraded | $300 to $350 | $180,000 to $210,000 | $300,000 to $350,000 |
| High end | $350 to $400 | $210,000 to $240,000 | $350,000 to $400,000 |
Bathrooms add on top. Each full bath upstairs adds roughly $12,000 to $25,000, depending on tile and fixtures, because it brings new supply, drain and vent lines up through a house that wasn’t built with them in mind. The calculator adds those for you.
What’s in the price and what isn’t
A Wright’s second-story budget covers structural engineering and stamped drawings, permits and inspections, demolition and roof tear-off, temporary weather protection, foundation and first-floor reinforcement, framing, the new roof, windows, siding and the exterior tie-in. It also covers full mechanical, electrical and plumbing for the new floor, the staircase, insulation, drywall, trim, paint and flooring. You’ll get daily photo updates the whole way through.
It doesn’t cover furniture, your relocation, landscape repair beyond the work zone, or a service or furnace upgrade if the new floor outgrows what you have. Conditions found once the roof comes off, like knob-and-tube wiring or water damage in the attic, come to you as a written change order with the cost and schedule effect before work continues. Our design-build process explains how that conversation runs.
The costs that never show up in a construction bid
A full roof removal means you move out for four to eight weeks. There’s no version where the roof comes off and you sleep under it. Budget for two months of a rental, a storage unit and more takeout than you’d like. That money is real, and no contractor’s proposal will include it, ours included.
Time is the other cost. Construction runs five to eight months from permit approval. Add design and permitting and the whole project takes eight to twelve months. A partial addition over one wing sometimes lets you stay home through the whole build, which is worth designing toward if moving out is the deal breaker.
What drives the price up or down
- Your foundation. Most 1940s to 1970s Michigan houses sit on concrete block. Sound block can usually carry a second floor with reinforcement. Crumbling mortar or a bowed wall gets fixed first, and that’s added cost.
- Footprint shape. A simple rectangle over a ranch is the cheapest floor to add. Wings, offsets and hips add framing and roof complexity.
- The stair. A new staircase takes first-floor space. If it means moving a wall or a bathroom downstairs, that’s part of the scope.
- Mechanical capacity. An older furnace or a 100-amp panel may not carry another floor. A new HVAC system runs about $5,000 to $12,000, and a panel upgrade about $2,500 to $5,500.
- Zoning. Height caps and nonconforming setbacks can turn a building permit into a variance request, which adds two to four months.
Second story vs. building out vs. moving
A ground-level addition runs $200 to $400 per square foot, so going out is usually cheaper per foot. Going up wins when your lot is tight, setbacks block a footprint expansion or you don’t want to give up the yard. Run both on the home addition cost calculator before you decide.
Moving is the third option, and it deserves an honest look. Selling costs, a higher mortgage rate and the price gap between your house and the next one up can add up to a big share of what the addition would cost. If you love the street and the schools, building up keeps both. If you don’t, a second story is a lot of money to spend on a house you’re lukewarm about.
Paying for a second-story addition
Most homeowners fund a second story with a home equity line, a cash-out refinance or a renovation loan that lends against the finished value. A second floor adds bedrooms and square footage, which is what appraisers price, so the after-improvement value often supports the loan. Our renovation financing page walks through the options.
Questions homeowners ask about second-story cost
How much does it cost to add a second story to a ranch in Michigan?
A full second floor over a 1,200-square-foot ranch runs $312,000 to $480,000 in Southeast Michigan. A partial floor over part of the house, around 600 square feet, runs $156,000 to $240,000. Foundation condition is the biggest unknown, which is why an engineer looks at it before a fixed price goes out.
Is a second story cheaper than an addition out the back?
Usually not per square foot. Building out runs $200 to $400 per square foot versus $260 to $400 to go up. A second story can still be the cheaper project overall when it avoids a new foundation, a variance or the loss of yard you’d otherwise have to replace.
Can my foundation hold a second floor?
Often, with help. Most Michigan houses need some reinforcement, such as underpinning piers, footing extensions, basement beams or sistered first-floor framing. The engineer decides after looking at the actual foundation. If the answer is no, we’ll say so and point you at a dormer or attic option instead.
How accurate is the calculator?
It’s a planning range, not a quote. It uses the same per-square-foot band we price from in Southeast Michigan, but your foundation, roof shape and finishes decide where in that band you land. The fixed number comes after a site visit, an engineering review and a design you’ve signed off on.
Get a fixed price for your second floor
Wright’s designs and builds second-story additions across Ann Arbor, Ypsilanti and the rest of Southeast Michigan. One team handles the engineering, permits and construction, and the price you approve is the price you pay. See finished work in our projects, then book a consultation to get a fixed-price proposal for your house.
