ICC A117.1-2017: the technical companion to ADA/IBC accessibility. Chapter 3: building blocks — clear floor space 30x48in, knee clearance 27in high x 8in deep, forward reach 48in max/15in min, side reach 48in max. Chapter 4: accessible routes — 36in min width (44in at turns), 60in passing space, max slope 1:12 (ramp), 1:48 (walking surface). Chapter 5: general site — parking (96in van + 96in access aisle), curb ramps. Chapter 6: plumbing — WC 18in centerline, 17-19in AFF seat, grab bars (42in side, 36in rear), lavatory 34in max rim, 27in knee clearance. Chapter 7: communication — visual alarms (75 candela in 20x20ft room), TTY, assistive listening (25% of fixed seating). Chapter 8: assembly — dispersed wheelchair spaces, companion seats, line-of-sight over standing spectators. Referenced by IBC Chapter 11 and Fair Housing Act.