Seattle NR3
Neighborhood Residential 3
Seattle zone NR3 (Neighborhood Residential 3) permits ADU construction. Detached ADUs up to 1,000 sqft are allowed, with a 22ft maximum height.
Last updated 2026-05-15Refreshing this quarter
| DADU permitted | Yes |
|---|---|
| AADU permitted | Yes |
| Two ADUs per lot | Yes |
| Max DADU size | 1,000 sqft |
| Max AADU size | — |
| Max height | 22 ft |
| Rear setback | 5 ft |
| Side setback | 5 ft |
| Lot coverage | 40% |
Higher density; 22ft DADU height with green-roof bonuses up to 24ft.
Seattle NR3 ADU questions
Can I build a DADU on a Seattle NR3 lot?
Yes. Seattle zone NR3 allows detached ADU construction up to 1,000 sqft, with a 22 ft height limit. Setbacks and lot coverage still apply — see the spec table above.
Go deeper: Read the DADU vs AADU in Puget Sound: which to build (2026) guide
Can I build an AADU on a Seattle NR3 lot?
Yes. Attached ADUs are permitted in Seattle zone NR3. AADUs typically share utilities and structure with the primary house.
Go deeper: Read the DADU vs AADU in Puget Sound: which to build (2026) guide
Can I build two ADUs on one Seattle NR3 lot?
Yes. Seattle NR3 permits a DADU + AADU combination on a single qualifying lot, subject to lot coverage and parking rules.
Go deeper: Read the DADU vs AADU in Puget Sound: which to build (2026) guide
What are the setback and height limits for Seattle NR3?
Seattle NR3 caps height at 22 ft, with a 5 ft rear setback and 5 ft side setbacks. Maximum lot coverage is 40%.
How do I confirm NR3 applies to my specific Seattle parcel?
Pull the parcel on the Seattle GIS viewer or send us the address — we verify zoning, overlays (critical area, shoreline, historic), and the practical buildable envelope at no cost.
Go deeper: Read the Seattle Design Review for ADUs: when it applies (2026) guide
Adjacent data
INTERNAL_LINKS / Deep Map