ADUs in Whatcom County
The ADU process is going to get easier and we are studying and updating this ADU Resource page. Here is what we understand to be current, Oct 2023.
ADUs (or in-law suites) supply a lot of answers to Whatcom County housing problems, but there are still major hurdles homeowners face when it comes to building one. The principal is cost; an ADU can easily cost nearly as much as building a new house. (Read here about why per square foot costs might be on par with similarly constructed larger homes.) An ADU can provide an immense amount of flexibility around living arrangements and increase the value of your property. Beyond cost, you’ll need to know if your lot can accommodate an ADU and what it will look like. Depending on where you live these requirements differ. It is important to know now, that we expect all jurisdictions will change guidelines at the end of 2025. In some cases owner occupancy will no longer be required under future changes, but only in some areas.
Whatcom County
At this time, Whatcom County has not adopted the new guidelines we don’t expect to see an update to that information until Dec of 2025. In a nutshell, according to the Whatcom county code 20.80.910 Accessory dwelling units standards currently allow only one ADU per property and owners must occupy the property. There are many lot sizes across the county and each property has specific zoning limitations for ADU and DADU.
When Whatcom County adopts the new regulations, it will only change things for property owners in the urban growth areas and in cities themselves. The county will defer to each city in regard to how the city wants to adopt the regulations.
Additional Whatcom County Resources
City of Bellingham
WHAT TYPE OF PERMIT:
TYPE I ADU permit is a streamlined version and no longer requires notification of surrounding property owners.
Type II ADU permit with minor modifications requires notifying neighbors and a public comment period.
Type III ADU permit for new larger buildings that include a D-ADU requires more public notice and is subject to being appealed in Superior court.
WHERE: ADUs are allowed in most areas but not all of the city of Bellingham. It might be possible to have two ADU’s along with a single family home. ADUs are not allowed in the Lake Whatcom watershed within the city limits.
SIZE: 1,000 Square feet, no higher than 24 feet, and/or subject to other limitations that may be less.
OWNER OCCUPANCY: Required in single-family zones only. (this is expected to change in late 2025)
ADU OWNERSHIP: Allowed in the same way a condo is allowed to be owned. The land belongs to the homeowner, but the ADU building can be owned by others.
PRE-EXISTING ADU: These units may be permittable and in some cases, even if the building is non-conforming. Individual research is required for this type of building as with all ADU permits.
Additional City of Bellingham Resources:
Blaine
Currently Blaine is working on a Housing Action Plan that could ease the ADU process. Currently, ADU includes a conditional use process and it is expected that may change. Blaine already has a templated guide to make the process easier. We will be checking on the updates from Blaine that are expected to happen in 2024. In the interim, it would be best to contact the Blaine Community Development Services Director for assistance with ADU projects.
Additional City of Blaine Resources
Everson
Currently, the city of Everson allows accessory dwelling units attached to a single family home that is on a minimum sized lot of 10,000 sq. ft. according to their Municipal code 19.23.025. We will update here as information becomes available.
Additional City of Everson Resources
Ferndale
Ferndale’s process right now allows 1 ADU per lot. The ADU size is 800 sq. ft. or less and all ownership belongs to the single-family home owner. Information on if and when the city of Ferndale will incorporate changes to its code will be updated on this page as we learn more. We can guess that Ferndale will have some good news in the future about ADU policies if their recent ADU Metallica T-shirt contest is an indicator of their encouraging ADU attitude!
Additional City of Ferndale Resources
Lummi Nation
Information regarding ADUs in Lummi Nation is pending. This will be updated as information is made available.
Additional Lummi Nation Resources
Lynden
Currently, the city of Lynden “encourages the availability of affordable housing to all economic segments” including ADUs in their Municipal Code which can be found specifically in Chapter 19.20. We look forward to updates as they are made available.
Additional City of Lynden Resources
Nooksack
Currently, Nooksack provides opportunities for housing through the Nooksack Housing Department. We will update this page if ADU information becomes available in Nooksack.
Additional Nooksack Resources
Whatcom County ADU Contact Information
Whatcom County
Planning and Development Services
Administrative Office
5280 Northwest Drive
Bellingham, WA 98226
360-778-5900
pds@co.whatcom.wa.us
https://www.whatcomcounty.us/358/Planning-Development-Services
Bellingham
City Hall
210 Lottie Street
Bellingham, WA 98225
(360) 778-8000
info@cob.org
Planning and Community Development Department
Email: planning@cob.org
Phone: (360) 778-8300
Fax: (360) 778-8301
Call the planning department and you will be transferred to the planner of the day.
For more department resources here.
Blaine
435 Martin St, Suite 3000
Blaine, WA 98230
Ph. (360) 332-8311
Fax. (360) 543-9978
Directions to Blaine City Hall
Link to Land Use Permit Development Applications can be found here.
Everson
City Hall
111 W Main Street/ P.O. Box 315
Everson, WA 98247
(360) 966-3411
https://www.ci.everson.wa.us/index.php
Forms that maybe needed can be found here.
Ferndale
2220 Main Street
Ferndale, WA 98248
(360) 384-4302
https://www.cityofferndale.org/
Accessory Dwelling Units
Lummi Nation
Lummi Nation Planning Department
(360) 312-2343
Lynden
300 4th St
Lynden, WA 98264
(360) 354-1170
cityhall@lyndenwa.org
www.lyndenwa.org
Planning & Community Development Department
(360) 354-5532
planning@lyndenwa.org
More information on the process
All Planning and Community Development Department downloadable forms and applications can be found HERE.
All forms and applications for the City of Lynden can be found HERE.
Nooksack
City Hall
103 W. Madison St.
Nooksack, WA 98276
(360) 966-8531
info@cityofnooksack.com
http://cityofnooksack.com/
Forms that maybe need to be completed are here
Sumas
City Hall
433 Cherry Street/P.O. Box 9
Sumas, WA 98295
Phone: 360-988-5711
https://www.cityofsumas.com/
Here is where you can find the forms that may needed to be completed for your project.