Section R302.1: Exterior walls — fire separation distance <3 ft: 1-hr rated with 0% openings. 3-5 ft: 1-hr rated with 25% openings. ≥5 ft: no rating, unlimited openings. Projections within 2 ft of property line limited. Section R302.2: Townhouse separation — 1-hr common wall (each side rated independently) or 2-hr common wall (tested as assembly). Through-penetration protection. Section R302.3: Two-family dwellings — 1-hr separation between units. Section R302.5: Dwelling-garage separation — 1/2-hr gypsum (5/8 Type X) on garage side of common walls. Self-closing door (20-min rated). No openings from garage to sleeping rooms. Section R302.6: Dwelling-garage fire sprinklers — IRC P2904 sprinkler system permits reduction of garage separation. Section R302.7: Under-stair protection — enclosed space under stairs protected with 1/2 in gypsum. Section R302.11: Fireblocking — required at ceiling/floor levels, soffits, stair stringers, 10 ft intervals in concealed spaces.