St. Paul's 2023 zoning reform is one of the most ADU-friendly ordinances in Minnesota. Here's what homeowners need to know about size limits, setbacks, and permits.
| ADU type | Max size | Max height | Notes |
|---|---|---|---|
| Detached (accessory building) | 800 sq ft or 75% of the principal dwelling's floor area, whichever is greater | 25 ft | Requires its own lockable entrance, full kitchen, and full bathroom |
| Attached / internal (basement, addition) | Sized within the primary structure | Same as primary structure | Common for basement conversions |
Lot size minimum: eliminated under Ordinance 23-43 - no minimum lot size is required to qualify.
| Units per lot | Up to 2 ADUs permitted in addition to the principal dwelling |
| Owner-occupancy | Not required - you don't need to live on site to rent out an ADU or the main house, provided each is properly rental-licensed |
| Parking | No additional off-street parking required for the ADU |
| Rental license | A separate St. Paul rental license is required for each unit before placing tenants |
| Historic districts | Properties in the Hill District or on Summit Avenue require additional design review |
| Building code | Must meet 2020 Minnesota Residential Code standards |
Check your property's zoning district and whether historic design review applies (Hill District / Summit Avenue).
Include a site plan showing setbacks and the ADU's relationship to the principal dwelling.
Standard review typically takes 2–4 weeks; historic districts add roughly 4–8 weeks for design review.
Apply for a separate rental license for each unit before placing tenants.
Timelines are approximate and vary by application completeness and whether design review is required - confirm current figures with DSI.