ADU Permitting in Bellingham & Whatcom County

Our dedicated permit specialist handles every aspect of your ADU permits — site plans, land use (county properties), and building permits. Free when we build your ADU.

Free Permits When We Build Your ADU

Most builders hand you a permit bill on top of construction costs. We don't. When you build with Bellingham ADU Builders, your entire permit package — site plans, land use permits, building permits, engineering — is absorbed into your construction contract at no additional charge.

Free

Feasibility Study

Free

Permit Package

Perfect

Build

How Our Permit Package Works

ADU permitting in Whatcom County involves navigating state mandates (HB 1337), city-specific ordinances, county regulations, and environmental overlays. Most homeowners underestimate the time and expertise required to get permits approved on the first submission.

Our permit package covers everything: professional site plans, land use permits (required for unincorporated county properties — not needed within city limits), and building permits with tiered pricing based on project complexity. The total typically runs less than 1% of your project cost, plus $1,000–$2,000 in government filing fees.

Need permits without a build contract? We offer the permit package as a standalone service — see our pricing structure below. But most clients choose the full build path where permits are included at no charge.

City vs. County: What Permits Do You Need?

Within City Limits

Bellingham, Ferndale, Lynden, Blaine, Everson

  • Site plan
  • Building permit
  • Land use permit not required

Faster & simpler process

Unincorporated County

Rural Whatcom County, UGA areas

  • Site plan
  • Land use permit (county requirement)
  • Building permit

Additional land use step required

Not sure which jurisdiction you're in? Our free feasibility study determines this automatically.

Standalone Permit Pricing

For homeowners who need permits without a build contract. All fees are waived when you build with us.

Site Plan

Component Pricing Details
Base Site Plan Flat rate Standard residential lot under 0.5 acres
Large Lot Surcharge Per-acre cost Properties over 0.5 acres
Site Plan Drafting 10% to surveyor Professional site plan by Jordan

Building Permits (Tiered by Complexity)

Standard

Garage conversion, basement ADU, simple attached

Straightforward projects with minimal structural changes

Moderate

Attached addition, above-garage unit

Projects requiring moderate engineering and design coordination

Complex

Custom detached DADU, multi-story, challenging site

Full custom design with structural engineering, site challenges, or CUP process

Total Standalone Permit Package

Less than 1% of total project cost + $1,000–$2,000 government fees

Typical total

$4,000–$6,000

Build with us? Permits are on the house.

When you sign the Letter of Intent and build with Bellingham ADU Builders, the entire permit package cost is absorbed into your construction contract. You pay nothing extra for permitting.

What's Included

  • Full zoning verification for your specific parcel
  • Setback and lot coverage analysis
  • Utility connection assessment (sewer, water, electrical)
  • Critical areas review (wetlands, flood zones, steep slopes)
  • Lake Whatcom Watershed check
  • Professional site plan by licensed surveyor
  • Land use permit application and management (county properties)
  • Building permit drawings and structural engineering
  • Building permit submission and follow-through
  • Ongoing communication with planning staff through approval
  • Pre-application meeting with planning department (if needed)

Learn More About ADU Permitting

Read our detailed permit guides: Bellingham permit process, Whatcom County permits, permit cost breakdown, and realistic timelines.

Ready to build? Explore our detached ADU and attached ADU construction services.

Frequently Asked Questions

What does the Full Permit Package include?

The package covers your complete permitting process: site plan preparation, zoning verification, setback analysis, utility assessment, critical areas review, land use permit application (for county properties), building permit drawings, engineering, and submission management. When you build with us, the entire permit cost is included in your construction contract — you pay nothing extra.

Do I need a land use permit?

Only if your property is in unincorporated Whatcom County. Properties within city limits (Bellingham, Ferndale, Lynden, etc.) do not require a separate land use permit — you go straight to building permits. Our feasibility study determines your jurisdiction automatically.

How much does permitting cost as a standalone service?

Our permit package typically totals less than 1% of your project cost, plus $1,000-$2,000 in government filing fees. However, when you build with us, the entire permit package is included at no additional charge — it's absorbed into your construction contract.

What type of permit does my ADU need?

Most ADUs in Bellingham qualify for a Type I permit — the fastest path with no neighbor notification required. Type II is needed for projects creating 7+ dwelling units. A Conditional Use Permit (CUP) is required for detached ADUs exceeding 1,000 sq ft, requiring a hearing examiner review.

How long does the ADU permitting process take?

In Bellingham, Type I permits typically take 4-6 weeks. In unincorporated Whatcom County, expect 6-10 weeks. Rural areas may take 8-12 weeks due to additional septic and well reviews. These timelines assume a complete initial submission — which is why having a specialist matters.

What if my property doesn't qualify for an ADU?

If our analysis determines your property doesn't qualify, we'll tell you honestly. We'd rather give you a straight answer than waste your time and money.

Do I need a permit for a garage conversion?

Yes. Converting a garage to a dwelling unit requires a change-of-use permit plus building permits for the conversion work (plumbing, electrical, insulation, egress windows). The good news: existing structure conversions are allowed even if the structure doesn't meet current setback or lot coverage standards.

Check Your Property's ADU Potential

Get a free feasibility report based on Whatcom County GIS data and 2026 land use rules.

Get Your Free Feasibility Study

Or call us directly: (360) 594-0120

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