Dormer or full second floor?
| Shed dormer | Full second floor | |
|---|---|---|
| Space added | Rear half of the upstairs becomes full height | Entire upstairs becomes full height |
| Typical cost | $95K–$160K finished | $200K–$350K+ |
| Street look | Still reads as a Cape | Becomes a colonial |
| Timeline | 10–16 weeks | 4–7 months |
| Can you stay home? | Usually | Often not |
Foundation and structure
A second story adds load. We have an engineer confirm the foundation and first-floor framing can carry it, and design any reinforcement needed. That check happens before you commit.
Typical cost
A full second-story addition on a Cape typically runs $200,000 to $350,000 or more, depending on size and finish.
Use the dormer cost calculator →
Questions about cape cod second floors
Is a second floor cheaper than moving?
Often, once you add up realtor fees, transfer taxes, moving costs, and a higher purchase price. It's also the only way to stay in a neighborhood you love and get the space you need.