ADU Builder Index

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Haas Development & Const Co David Hass Delafield

0completed ADU permits
1total ADU permits
2025–2025active years on record
median est. project cost

Washington state license

No exact business-name match in the WA L&I registry — this builder may hold a license under a different legal name. Check the registry directly.

Permit record

Every ADU-related permit in covered city records naming this contractor. Links go to each city's official permit portal.

PermitCityIssuedStatusEst. costAddressDescription
24 129550 BR2025-09-03Issued1505 143rd Ave NEBODELL COTTAGE — NEW BACKYARD COTTAGE - 393GSF. Includes clearing & grading. Does not include mechanical, electrical or plumbing. Guest Cottage Agreement Recording Number: 20250408000222

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