Edmonds ADU rules
✓ Verified against code · August 19, 2026
Current rules under ECDC 16.20.060 (Edmonds Community Development Code), adopted by Ordinance 4360 (amended by Ords 4397, 4398), in effect since June 19, 2024. Edmonds complied with HB 1337 a full year early — Ordinance 4360 took effect June 19, 2024 — then reshaped the details again in mid-2025 with its middle-housing rezone (Ord 4397) and a follow-up amendment (Ord 4398). Note the city's own handout still cites the old code section number.
Common questions, answered from the code
How big can an Edmonds ADU be?
It depends on your zone: 1,200 sq ft of gross floor area in LDR-L and LDR-M, 1,000 sq ft in LDR-S — and garage space doesn't count, since GFA excludes unconditioned areas.
ECDC 16.20.060(C) · Permalink
Do I need parking for an Edmonds ADU?
Not for the first one. A second ADU needs one space (tandem is fine, and it must get a Level-II EV charging circuit) — unless you're within a half mile of a major transit stop, where it's waived too.
ECDC 16.20.060(C); 17.50.020 · Permalink
I recorded an owner-occupancy covenant under the old rules — am I still bound?
No. Ordinance 4360 bars the city from enforcing previously recorded ADU covenants and authorizes staff to release them on request.
Ord 4360 §10 · Permalink
What will Edmonds impact fees cost on an ADU?
Unlike several neighboring cities, Edmonds charges them — and the structure changed January 1, 2026: park impact fees are now $1.35 per sq ft of residential space under the 2026 Fee Guide (a 1,000 sq ft ADU ≈ $1,350; the flat $1,367.03 figure still circulating is the superseded 2025 rate), plus transportation fees per ITE trip rates and a sewer general facility charge per unit. Budget for utilities too — one meter and one lateral per parcel, with a 6-inch sewer line where more than one unit is served.
2026 Planning & Development Fee Guide (eff. 1/1/2026); ECDC 16.20.060(D),(F) · Permalink
When did Edmonds' current ADU rules take effect?
The core rules on June 19, 2024 — a year ahead of the state deadline — with the zone structure and setback details revised in July 2025 by the middle-housing package (Ords 4397/4398). Anything written before mid-2025 may cite superseded zone names and setbacks.
Ord 4360; Ord 4397 · Permalink
The rules at a glance
| ADUs allowed per lot | Two ADUs per detached single-family principal dwelling — one attached plus one detached, two attached, or two detached. Not available on townhouse, duplex, plex, or cottage-housing lots.ECDC 16.20.060(B) |
| Maximum size | Gross floor area of 1,200 sq ft in the LDR-L and LDR-M zones, 1,000 sq ft in LDR-S. GFA counts interior habitable area including basements and attics but excludes unconditioned space such as a garage.ECDC 16.20.060(C); 21.35.013 |
| Detached ADU height | 24 ft for detached ADUs; attached ADUs follow the 25-ft primary-dwelling limit.ECDC 16.20.060(C) |
| Detached ADU setbacks | Street/side setbacks per zone (LDR-L 25/10 ft; LDR-M 25/7.5; LDR-S 20/5). DADU rear setbacks: 25 ft in LDR-L; 15 ft in LDR-M (reducible to 10 if the DADU is 15 ft or shorter); 10 ft in LDR-S (reducible to 7.5). Zero rear setback where the rear lot line abuts a public alley.ECDC 16.20.060(C) + footnotes |
| Off-street parking | First ADU: no parking. Second ADU: one off-street space (tandem allowed) — waived within a half mile of a major transit stop. A Level-II EV circuit is required for the second ADU's space.ECDC 16.20.060(C); 17.50.020 |
| Owner-occupancy | None. Ordinance 4360 repealed the old owner-occupancy chapter entirely, barred enforcement of previously recorded ADU covenants, and authorized staff to release them.Ord 4360 §§8, 10 |
| Lot coverage / floor area | 35% structural lot coverage on all lots — the council cut it from the proposed 45%. No FAR.ECDC 16.20.030 (Ord 4397) |
| Permit path & timeline | Residential building permit only — the old conditional use permit is gone. Apply via MyBuildingPermit.com. No published review timeline.Ord 4360 §7; city B2 handout |
Worth knowing
- Impact fees are NOT waived — and the math changed January 1, 2026: the 2026 Fee Guide moved park impact fees to $1.35 per sq ft of residential space (superseding the earlier flat $1,367.03-per-ADU rate that many guides still quote), plus transportation fees per ITE rates and a sewer general facility charge per ADU.
- One water meter and one sewer lateral per parcel — private submetering allowed; the sewer line must be 6-inch where serving more than one unit.
- DADUs may be created inside existing detached garages, even nonconforming ones; manufactured and modular units are allowed.
- Old recorded owner-occupancy covenants from the previous regime are unenforceable and releasable on request.
- The DADU prohibition in Critical Aquifer Recharge Areas sunset on June 30, 2025.
On our watchlist
Ordinance 4398 (July 2025) is the last word on the ADU standards table — including whether the LDR-M DADU rear setback is 15 or 20 ft (the current city handout says 15; the Ord 4397 exhibit printed 20). We follow the city's April 2026 handout pending the codified text.
Whether any DADU restriction remains in Critical Aquifer Recharge Areas now that the sunset clause lapsed — unverified.
Check your parcel
The rules above are citywide — what you can build depends on your lot’s zone, size, and setbacks. Look yours up on the official viewers:
Primary sources
- Ordinance 4360 (adopted text)
- City B2 ADU handout (rev. 4/17/2026)
- Middle Housing code page (Ord 4397)
Other Washington cities
Bellevue · Bothell · Burien · Everett · Issaquah · Kent · Kirkland · Lynnwood · Olympia · Redmond · Renton · Sammamish · Seattle · Shoreline · Tacoma
Not legal advice. Every fact above cites the code section it comes from — check the cite, or ask your city’s planning department to confirm your specific lot. Spotted an error or a new ordinance? See about to reach us; corrections are logged in the changelog.