In every building erected or altered after February 20 1917, except frame buildings, all walls or partitions forming interior light or vent shafts shall be built in accordance with the requirements for stair and elevator shafts in new buildings as specified in Section 5-25-830. The walls of the dumbwaiter shafts, except those in dwellings which extend only one story above the basement or cellar, shall be of fire-resistive construction and shall be not less than three inches thick, if constructed of brick, hollow or solid blocks, or of steel studding and metal lath with three-quarter inch of portland cement plaster on each side or a two-inch solid metal lath and portland cement plaster wall may be permitted, if securely anchored at each floor. The material and method of construction shall be as specified for stair and elevator shafts in existing buildings in Section 5-25-830. In frame buildings, outside the fire limits, the enclosure partitions of all such shafts may be constructed as provided in Section 5-25-830 for stair and elevator shafts in buildings existing on February 20 1917. Where a dumb-waiter shaft does not extend through the roof, the top of the shaft shall be of fire-resistive construction of the same thickness as the walls of the shaft. All openings in dumb-waiter shafts shall be protected by fire doors mounted in incombustible frames securely anchored to the walls. The walls of all light and vent shafts erected after February 20 1917 shall extend not less than three feet above the roof level, except that when a shaft is covered by an incombustible ventilating skylight, the walls need not extend more than two feet above the roof. Masonry walls shall be properly coped. When metal louvres are used for ventilating purposes, the louvres or slats shall be riveted to the metal frame.

HISTORY: 1962 Code Section 47-1253; 1952 Code Section 47-1253; 1942 Code Section 7518; 1932 Code Section 7518; Civ. C. '22 Section 4633; 1917 (30) 77.