Attached in-law suite vs Detached ADU cottage
Both configurations create independent living space for family or rental income; the structural project, privacy profile, and regulatory framework differ. Florida's 2026 ADU rules clarified detached ADU permissions.
Attached in-law suite
Connected wing of the main house
Detached ADU cottage
Separate structure on the same lot
How they stack up.
| Dimension | Attached in-law suite | Detached ADU cottage |
|---|---|---|
| Cost (typical) | $140,000–$320,000 | $180,000–$400,000 |
| Privacy from main house | Moderate; shared wall | High; separate building |
| Setback requirements | Same as primary structure | Specific ADU setbacks per county |
| Septic capacity check | Required for added fixtures | Required + sometimes separate system |
| Utility metering | Shared | Can be separate (where allowed) |
| Rental income potential | Restricted by some HOAs/zones | Generally permitted in most NE FL counties |
| Construction time | 16–22 weeks | 20–28 weeks |
Attached is the right call for aging parents who want close caregiving access, when lot size constrains a detached footprint, and when budget favors a single connected build over a separate structure.
Detached is the right call when privacy matters most (adult children, long-term guests, rental income), when the lot supports a separate footprint, and when separate utility metering is desired.
- Florida ADU rules update 2026
- Clay County, Duval County, St. Johns County zoning ordinances
Tivey services for this work.
Recent field notes.
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