Internal ADUs are a permitted use across every Weber County city thanks to Utah's HB 82. But the rules around detached units, parking, owner-occupancy, and design standards vary. Here's the city-by-city quick reference. Updated October 2025.
For the HB 82 background, see our plain-English HB 82 guide. For the Davis County version, see the Davis County cheat sheet.
Ogden
- Internal ADUs: Permitted use per HB 82 in residential zones
- Detached ADUs: Allowed in many residential zones; Ogden is one of the more ADU-friendly cities in northern Utah historically
- Carriage houses on top of detached garages have a long tradition in older Ogden neighborhoods — usually feasible structurally with engineering
- Historic overlay: Some neighborhoods have preservation rules that affect external structural work
- Building department: Ogden City Building Services
Roy
- Internal ADUs: Permitted use per HB 82
- Detached ADUs: Subject to lot size, setback, and lot-coverage rules
- Older housing stock means more existing-condition evaluation needed before any ADU work
- Building department: Roy City Building Department
North Ogden
- Internal ADUs: Permitted use per HB 82
- Detached ADUs: Subject to local zoning
- Bench lots may face additional review for hillside or geo-hazard considerations
South Ogden
- Internal ADUs: Permitted use per HB 82
- Mostly older housing stock in established neighborhoods — many ADU conversions are basement or above-garage
Hooper
- Internal ADUs: Permitted use per HB 82
- Detached ADUs: Often more practical here than in denser cities because of large lot sizes
- Many lots are agricultural-residential with their own use rules; confirm zoning first
Plain City, West Haven, Marriott-Slaterville
These west-side Weber County cities follow HB 82 for internal ADUs and generally allow detached units subject to lot size and setback rules. The bigger lots mean detached ADUs are more practical here than in Ogden proper. Always confirm with the specific city building department.
Riverdale
- Internal ADUs: Permitted use per HB 82
- Smaller city — quick permit turnaround in our experience
The universal rules across Weber County
- Building permit always required
- Stamped structural plans for any new framing, openings, or significant work
- IRC compliance with local snow load (varies by elevation; bench cities can be 45+ psf)
- Egress windows in any sleeping room — basement ADUs almost always need an engineered cut
- Fire separation between units (typically 1-hour rated assembly)
What we'd do next
Send your address and a description of what you're planning. We'll come back same day with a fixed fee, a real read on your specific city's requirements, and a timeline. See our ADU services page for the full scope.