Multi-family: 3+ units governed by IBC (not IRC). R-2 occupancy. Types: garden-style (2-3 story, Type VB wood), mid-rise (4-7 story, Type IIIA/VA wood over Type IA podium), high-rise (>75 ft, Type IA/IB steel/concrete). Key requirements: fire-rated separation between units (STC 50, IIC 50), sprinklers (all R-2), accessible units (Type A 5% in I-1/R-1, Type B per Ch 11). Parking: per zoning. Timeline: 12-36 months. Budget: $200-$500/sf.