DADU Rules in Bellevue: What Eastside Homeowners Should Know

Bellevue: Premium DADU Market

Bellevue’s combination of high property values, strong tech-driven rental demand, and relatively large residential lots makes it an excellent market for DADU construction. As the Eastside’s largest city, Bellevue has developed its own ADU-friendly regulations that align with HB 1337 while reflecting the city’s unique character.

Bellevue DADU Regulations

Key Rules

Maximum size: 1,000 square feet
Two ADUs allowed: Per HB 1337 requirements
Minimum lot size: Varies by zone — typically 3,200+ sq ft in residential zones
No owner occupancy requirement
No additional parking required for ADUs
Height: Must comply with base zone height limits

Setbacks

Side and rear: 5 feet minimum
Front: Same as primary home
Special considerations: Some Bellevue neighborhoods have design guidelines that affect exterior appearance

Bellevue Construction Costs

Eastside construction costs run 10–15% higher than the King County average due to higher labor costs and premium expectations:

All-in cost range: $450,000–$700,000 for a typical 800 sq ft DADU
Permit fees: $45,000–$85,000
Per-square-foot construction cost: $320–$420

For a detailed breakdown, see our construction cost guide.

Bellevue Rental Market

Bellevue’s proximity to Microsoft, Meta, Amazon’s Eastside offices, and other tech employers creates exceptional rental demand:

Studio/1-bed DADU: $2,200–$3,200/month
2-bed DADU: $2,800–$3,800/month
Annual gross income: $26,400–$45,600

Tech workers relocating to the Eastside often prefer DADUs for their privacy and residential setting. See our rental income guide.

Bellevue Permit Process

Department: Bellevue Development Services
Timeline: 3–6 months typical — generally efficient review process
Submission: Online through the city’s permit portal
Pre-application: Available and recommended for sites with unique conditions

Bellevue Neighborhood Opportunities

West Bellevue (Medina, Clyde Hill adjacent)

Large lots with established trees and significant setback areas
Premium finishes expected to match neighborhood character
Highest rental rates on the Eastside

Central Bellevue (Downtown adjacent)

Smaller lots but excellent transit access
Strong demand from downtown workers
Walking distance to restaurants, shopping, and Light Rail

East Bellevue (Crossroads, Lake Hills)

More affordable properties with good DADU ROI potential
Family-oriented neighborhoods
Good lot sizes for DADU construction

Factoria/Newport/Somerset

Larger lots on hillsides — foundation choice is especially important
Many properties have views that DADUs can take advantage of
Strong property values support premium DADU investments

Tips for Bellevue DADU Projects

Match the quality. Bellevue buyers and renters expect premium finishes. Invest in quality materials and design.
Consider the trees. Bellevue has significant tree canopy — tree protection plans are common requirements.
Design for the neighborhood. Many Bellevue neighborhoods have strong visual character. Your DADU should complement, not clash. See our PNW design guide.
Factor in Eastside premium. Budget 10–15% above average King County costs for labor and materials.
Leverage the rental market. Eastside rents justify premium construction — a high-quality DADU rents faster and for more.

APEX DADU Knows the Eastside

We’ve built DADUs throughout Bellevue and the Eastside — we know the permit process, the neighborhood expectations, and the construction realities. APEX DADU delivers premium DADUs that meet Bellevue’s standards.

Contact APEX DADU for your Bellevue DADU consultation