I have an unpermitted ADU — can I make it legal?
✓ Verified against code · August 19, 2026
Yes. Burien's code provides an explicit legalization path: apply for the applicable permits and bring the unit into compliance.
Citation: BMC 19.17.070(3)
How current is this?
Burien’s ADU rules run under BMC 19.17.070 (Burien Municipal Code, post-Ordinance 868) (Ordinance 868). Ordinance 868 — Burien's comprehensive Title 19 rewrite for HB 1110/1337 — took effect July 9, 2025. Fair warning: the city's own ADU handout (last updated May 2024) still shows the pre-868 rules, including an 800 sq ft detached cap that no longer exists. We verified this answer against primary sources on August 19, 2026, and every change we catch is logged in the changelog.
More Burien ADU questions
- How big can a detached ADU be in Burien?
- Do I need parking for a Burien ADU?
- How tall can a Burien DADU be?
- What utility work should I budget for?
All Burien ADU rules → · Compare Washington cities →
Not legal advice — lot-specific overlays can change the answer for your parcel. The citation above points at the governing code section; check it, or ask the city to confirm.