How Edmonds Handles Accessory Structures: A Practical Guide

Edmonds maintains 27 local ordinances across all categories, and 3 of those deal specifically with accessory structures. Here is a breakdown of what the city actually requires, what is prohibited, and where Edmonds falls on the strict-to-permissive spectrum compared to other cities.

ADU Rules

Edmonds City Council adopted an ADU code update on June 11, 2024, complying with state HB 1337. Up to 2 ADUs (attached and/or detached) are allowed per single-family lot. Maximum ADU size: 1,200 sq ft. Maximum height: 24 ft. No owner-occupancy requirement. Impact fees capped at 50% of principal unit. Building permit required.

Key details: Maximum ADUs: 2 per single-family lot. Maximum Size: 1,200 sq ft. Maximum Height: 24 ft. State Mandate: HB 1337 (2023); adopted June 11, 2024.

Unpermitted ADUs face stop-work orders and removal or legalization requirements. Fines of $500–$2,000 apply for unpermitted construction. Properties with illegal ADUs may face title issues at sale.

Shed Rules

Sheds and detached accessory structures in Edmonds must comply with ECDC zoning setbacks and the Washington State Building Code (WAC 51-50). Permit requirements depend on size; small structures under 200 sq ft may be exempt from a full building permit but still must meet setback requirements.

Key details: Code: ECDC; WAC 51-50. Small Shed Exemption: Possible under 200 sq ft (confirm with building dept.). Setbacks: Must comply with residential zone requirements. Contact: Building Division: 425-771-0220.

Unpermitted structures receive a notice to either obtain a retroactive permit (with double fees) or remove the structure within 60 days. Fines of $100–$500 apply for non-compliance.

Garage Conversions

Garage conversions to living space or ADUs require a building permit under WAC 51-50 and ECDC. Conversions must meet all applicable zoning, energy code, and habitability standards. HB 1337 (2023) facilitates garage-to-ADU conversions with relaxed requirements for impact fees and design.

Key details: Permit Required: Yes — building permit (WAC 51-50). ADU Conversion: Facilitated by HB 1337 (2023). Standards: Energy code, habitability, zoning setbacks. Contact: Building Division: 425-771-0220.

Unpermitted garage conversions face fines of $500–$2,000, mandatory permit acquisition (double fees), and may need to be restored to garage use if code requirements cannot be met.

The Bottom Line

Edmonds's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Edmonds is broadly strict or permissive.

Keep in mind that Edmonds can amend these rules at any council meeting. For the most current version of any rule mentioned here, check the specific ordinance page, where we track updates as they happen.