Typical Lot Size
7,000–15,000+
sq ft
Max ADUs
2
per lot
Permit Type
type_i
Timeline
6-10 weeks
Median Home Price
$450,000–$750,000
Est. ADU Rent
$1,200–$1,700/month
Neighborhood Overview
Blaine is a border city at the northern tip of Whatcom County, known for its Semiahmoo Resort area and proximity to the Canadian border. The city has been developing a permit-ready ADU program and offers unique opportunities with generally larger lots.
Border city with resort-area charm, waterfront properties, and a mix of year-round residents and vacation homeowners. Semiahmoo, Birch Bay, and historic downtown each have distinct character.
ADU Construction Allowed
Blaine qualifies for ADU construction under Bellingham's updated ordinance (BMC 20.10.036) and Washington's HB 1337.
- Detached ADUs (DADUs) allowed
- Attached ADUs allowed (basement, addition, above-garage)
- Up to 2 ADUs per lot
Why Build an ADU in Blaine
- Permit-ready ADU program in development — streamlined approval process
- Large lots provide excellent detached ADU potential
- Waterfront and resort-area properties command premium rental rates
- Cross-border appeal — Canadian visitors and workers create unique rental demand
- HB 1337 compliance ensures ADU rights on residential lots
Special Considerations
Coastal and waterfront properties may have Shoreline Management Act restrictions
Several HOAs in Blaine — while HB 1337 preempts ADU bans, design standards may still apply
Limited transit means parking requirements will apply for most properties
Vacation rental market can be seasonal — plan for year-round viability
Learn more about ADU regulations: Review Bellingham ADU laws, understand the permitting process, or see the complete cost breakdown for Whatcom County.
Ready to get started? Our free feasibility study analyzes your specific parcel in 48 hours.
Frequently Asked Questions
Can I build an ADU in Blaine?
Yes. Blaine allows ADUs on residential lots, and the city is developing a permit-ready program to streamline approvals. Both attached and detached ADUs are generally allowed, with up to 2 ADUs per lot under HB 1337 compliance.
Do Blaine HOAs affect ADU construction?
Several Blaine neighborhoods (including Semiahmoo) have HOAs. Under HB 1337, HOAs cannot prohibit ADU construction, but they may still enforce design standards for materials, colors, and architectural style. Review your HOA documents and contact us for guidance.
Are waterfront ADUs allowed in Blaine?
Waterfront properties may have additional restrictions under the Shoreline Management Act. Building within shoreline jurisdiction requires additional review and may limit where you can place an ADU. Our feasibility study checks all applicable shoreline overlays.
