Shoreline vs. Edmonds ADU rules
Shoreline and Edmonds split mainly on parking and fees. Shoreline requires zero off-street parking for any ADU citywide since a 2025 repeal, and guarantees a decision within 65 calendar days for its Type A review (SMC 20.30.140(A)(1)). Edmonds waives parking for a first ADU but requires one space plus a Level-II EV circuit for a second, with no published timeline guarantee. Edmonds also charges real impact fees — the 2026 park fee runs $1.35 per sq ft of residential space — where Shoreline's materials describe reduced ADU fees instead. Size caps run close: 1,200 sq ft in Shoreline, 1,200 or 1,000 in Edmonds by zone.
✓ Verified against code · August 19, 2026
Shoreline rules run under SMC 20.40.210 (Shoreline Municipal Code), adopted by Ordinance 1027 (amended by Ord 1043), in effect since January 28, 2025.
✓ Verified against code · August 19, 2026
Edmonds rules run under ECDC 16.20.060 (Edmonds Community Development Code), adopted by Ordinance 4360 (amended by Ords 4397, 4398), in effect since June 19, 2024.
Rule by rule
| Rule | Shoreline | Edmonds |
|---|---|---|
| ADUs allowed per lot | Two ADUs per lot, attached and/or detached — subject to the zone's units-per-lot density (NR3: 3 dwellings per lot, 4 within a half mile of a major transit stop; NR2: 4; NR1: no unit cap).SMC 20.40.210(A)–(B); Table 20.50.020(1) | 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 | 1,200 sq ft. An ADU inside the residence may exceed the limit if it occupies a separate floor sharing a common roof with the primary home. No garage/storage exclusion is stated in code.SMC 20.40.210(C) | 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 | No ADU-specific limit — base zone heights apply: 23 ft in NR3 (28 ft with a pitched roof), 30 ft in NR2 (35 pitched), 35 ft in NR1 (40 pitched).Table 20.50.020(1) | 24 ft for detached ADUs; attached ADUs follow the 25-ft primary-dwelling limit.ECDC 16.20.060(C) |
| Detached ADU setbacks | Side 5 ft; rear 10 ft (NR3/NR2) or 5 ft (NR1); front 10 ft. A DADU's side or rear setback drops to zero where it abuts an alley.Table 20.50.020(1) + Exception (25) | 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 | Zero. Shoreline repealed minimum vehicle parking citywide in August 2025 — not just for ADUs, for everything.Ord 1043 §1; SMC 20.50.390 (repealed) | 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 1027 struck the owner-occupancy requirement, the deed covenant, and the ban on selling the ADU separately.Ord 1027 §1 (Exh. A) | 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 | No building-coverage cap in the NR zones; hardscape is capped at 50% for one unit, rising with unit count (NR3 50% / NR2 60% / NR1 75% for 2+ units). No FAR.Table 20.50.020(1) + Exception (6) | 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 | Type A ministerial decision (staff-level, no hearing) plus a building permit — and Type A decisions are due within 65 calendar days, with the clock running from the completeness determination.Table 20.30.040; SMC 20.30.140(A)(1) | 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 |
Shoreline: worth knowing
- ADUs are a permitted use in every neighborhood-residential and commercial zone.
- ADUs may be sold separately from the primary home.
- City materials state ADUs pay reduced impact fees and require no street frontage improvements (exact rates live in the fee schedule).
- The citywide parking repeal makes Shoreline one of the most parking-permissive cities in the state — for any project, not just ADUs.
Shoreline: on our watchlist
Ordinance 1047 — the '2025 Development Code Batch Amendments' implementing state legislation — was adopted around early 2026; whether it touched SMC 20.40.210 is unverified pending the posted text. We re-check each pass.
ADU impact-fee dollar amounts (fee schedule, Ord 1042) not yet verified.
Edmonds: 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.
Edmonds: 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.
Full detail: Shoreline · Edmonds · back to the Washington hub. 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.