TORCHENGINEERING (480) 490-0064 Get a Quote

ADU Design in Seattle, WA

Seattle's construction market is driven by tech-campus expansion, port and maritime industry, and a wave of multifamily and mixed-use infill. The city sits in the Cascadia subduction zone and enforces one of the strictest energy codes in the country.

Get a Quote

Best price · Quotes back fast · PE stamps backed by Apex Grid Engineering

ADU plans, start to permit

Site plan, floor plans, elevations, structural design, and energy compliance — the complete drawing set your city needs to approve an accessory dwelling unit.

Designed for ADU rules

Many states now streamline ADU approvals with state-level rules on size, setbacks, and fees. We design to the current rules in your jurisdiction so nothing gets kicked back.

Fast and affordable

ADUs are small projects — they shouldn't carry big-firm fees or timelines. Lean process, best price, quotes back fast.

Project types

  • Tech office campuses and tenant improvements
  • Mid-rise and high-rise multifamily
  • Life-science and research labs
  • Waterfront and maritime industrial
  • Hospital and healthcare expansions
  • Mass-timber mixed-use

Everything else your project needs

MEP Engineering in Seattle

Mechanical, electrical & plumbing design — permit-ready drawings, best price.

Structural Engineering in Seattle

Structural design, analysis & PE stamping — permit-ready drawings, best price.

Civil Engineering in Seattle

Site civil & land development — permit-ready drawings, best price.

PE Stamping in Seattle

Licensed PE stamps on your plans — fast turnaround, best price.

Pool Engineering in Seattle

Pool structural, systems & permits — engineered for plan check approval.

Engineering Cost Guide in Seattle

Straight answers on what engineering really costs.

ADU Design nearby

Auburn · Bellevue · Bellingham · Everett · Kennewick · Kent · Olympia · Redmond · Renton · Spokane · Tacoma · Vancouver