New York City operates under the 2022 NYC Building Code, which is more stringent than the base IBC. The Department of Buildings (DOB) manages all permitting with typical timelines of 4-16 weeks depending on complexity. The city has a population of 8.3 million and covers 302 square miles. NYC requires extensive architectural and engineering reviews for most projects. The city is in Seismic Design Category C and requires compliance with NYC energy code (Chapter 28). Notable requirements include rigorous fire protection standards, mandatory lead-safe practices, and extensive environmental reviews. Permit costs average 0.5-1.2% of construction value. The city offers expedited review programs for projects meeting sustainability criteria.