Seattle adopts the 2024 International Building Code with Washington State amendments. The City of Seattle Department of Construction and Inspections manages permits with typical timelines of 3-10 weeks. The city has a population of approximately 753,675 and covers 142 square miles. Seattle is in Seismic Design Category D requiring enhanced seismic design and damping systems. The city has stringent environmental standards including air quality, water quality, and green infrastructure requirements. Notable requirements include acoustic performance, energy efficiency beyond code minimum, and tree preservation. Permit fees range from 0.6-1.0% of construction value. The city offers fast-track processing for LEED-certified projects and has established standards for sustainable development.