City of Bothell, WA

Common application types

• New Single Family Building Permit
• Single Family Addition/Remodel
• Accessory Dwelling Unit
• Residential Deck Permit
• Tenant Improvement
• Pre-Application Meeting
• SEPA Checklist

New homes and additions

New single-family submittals include a site plan with contours (2 ft intervals under 15% slope, 5 ft at 15% or steeper), a maximum hard surface coverage table per BMC 12.14.140(B), structural calculations, energy code worksheets and a geotechnical/soils report unless adjacent data shows one is unnecessary. Environmentally sensitive areas and surface waters within 200 ft must be shown. A Technical Information Report is required when impervious area increases by more than 5,000 sq ft, per the King County Surface Water Design Manual, along with a fire flow letter from the water provider and water and sewer availability certificates.

ADUs and middle housing

Bothell amended its comprehensive plan in Ordinance 2407 (adopted December 5, 2023, effective December 13, 2023) to allow middle housing in all residential zones, and Ordinance 2479, adopted December 9, 2025 and effective December 17, 2025, amends the middle housing provisions of BMC 12.06.140(B)(14). Per the City's ADU checklist, ADUs may be up to 1,200 sq ft; conversions of existing space may exceed this with Director approval but not 40% of the primary unit's gross floor area. Detached ADUs are limited to 30 ft in height, or 33 ft over an existing accessory structure.

Commercial tenant improvements and change of use

Tenant improvements are submitted through MyBuildingPermit.com with a Building Code Summary Worksheet and a plan set. A licensed architect or engineer must prepare plans for projects over 4,000 sq ft, first-time tenant spaces, or work affecting fire-rated construction, fire sprinklers or detection, egress, accessibility features or occupant load. A change of use may trigger sprinklers, ADA upgrades, added exiting or parking, structural upgrades and traffic impact fees.

Land use review

Pre-application meetings are required for Type I actions involving structures of 5,000 sq ft or more, for Type II, III and IVA actions and for new wireless communication facilities, and are optional for other types. Meetings are held within 45 days of the request being filed and paid, with a narrative, scaled site plan and preliminary elevations. Projects vest to zoning and land use ordinances when a complete subdivision or building permit application is submitted, not at pre-application.

Tips from SASHKOV

• Assembly, educational and institutional uses are strongly encouraged to hold a pre-application meeting early in design.
• Driveway grade must be less than 15% on new single-family site plans.
• Buildings over 30 ft need a narrative justifying height up to 35 ft.
• Request an address assignment (Form 54) before submitting a new single-family permit.

Where to apply

Permitting authority: Permit Center (Building Services and Permit Services Divisions). Online submittals: MyBuildingPermit.com.