Site feasibility, zoning review, plans, and the full permit package pulled and managed with the City of Bellingham or Whatcom County, so your build is approved before we break ground.
Most homeowners do not know that Bellingham changed its ADU rules in 2025, and the rules are the hardest part of an ADU. This service is the whole front end of a project: we run a site feasibility check against your zoning, setbacks, and lot size, draw the plans and elevations, handle the engineering, and pull and manage the full permit package with the City of Bellingham or Whatcom County.
The path is different inside city limits than outside, and the impact and connection fees, the setbacks, the stormwater rules, and the parking all run through different desks. We know which path your address is on and what each one needs. You can hire us for design and permitting on its own, or roll it into a full build, where the cost usually folds into the project. Either way, you end up with an approved permit and a clear path to construction.
What it actually costs.
ADU design & permitting $8,000 to $25,000
Design scopeA simple plan set vs. a custom design
EngineeringStructural, geotechnical, or stormwater engineering
JurisdictionCity of Bellingham vs. Whatcom County review
Rolled into buildOften folds into the full project cost
Our four-step process.
Site feasibility
We check your zoning, setbacks, and lot size against the 2025 rules and tell you exactly what your lot allows.
Plans and design
We draw the floor plan, elevations, and the details, and coordinate any engineering the unit needs.
Permit submittal
We assemble the full package and submit it to the City of Bellingham or Whatcom County.
Permit management
We answer the reviewer comments, make corrections, and carry it through to an approved permit.
Why hire a real crew for this.
Free, up-front feasibility check against the 2025 rules
Plans, elevations, and engineering coordinated for you
Full permit package submitted to the City or County
We answer reviewer comments and carry it to approval
Cost often rolls into the full build
Frequently asked questions.
How much does ADU design and permitting cost in Bellingham?
Design and permitting for an ADU in Bellingham usually runs $8,000 to $25,000, depending on how custom the design is and what engineering the unit needs. A straightforward plan set on a flat lot lands lower; a custom design with structural or stormwater engineering lands higher. When you build with us, this cost usually folds into the full project rather than being a separate bill.
Can I build an ADU on my lot in Bellingham?
Often yes, and more easily than a year ago. Under Bellingham's 2025 ordinance update (BMC 20.10.036), most single-family lots can now have up to two ADUs, a detached unit can reach 1,000 square feet and 24 feet tall, and off-street parking requirements are waived in the current ordinance window. Whether your specific lot works depends on setbacks and lot size, which is exactly what our free feasibility check confirms before you spend anything on design.
Who pulls the permit for an ADU in Bellingham?
We do, start to finish. We assemble the full permit package, submit it to the City of Bellingham if you are inside city limits or to Whatcom County if you are outside, and manage the review, including answering the reviewer comments and making corrections. You end up with an approved permit without having to navigate the counter yourself.
Ready for a free adu design & permitting quote?
Tell us about your project and your lot. We'll reply within 15 minutes during business hours.