15-8-470 Insulation.

   In all cases where finished flooring is applied directly to the floor construction or to sleepers, a resilient insulating base not exceeding one-half inch in thickness and applied directly to the floor construction shall be permitted.

(Prior code §  62-10.2)

15-8-480 Fire-resistive or noncombustible construction.

   (a)   In buildings of fire-resistive or noncombustible construction, all wood flooring and subflooring shall be applied directly to a floor construction of noncombustible material or may be attached to sleepers of combustible material. In buildings exceeding 100 feet in height, the space between the floor construction and the finished flooring shall be solidly filled with noncombustible materials.

   (b)   Combustible composition flooring not exceeding one-half inch in thickness may be applied directly to the noncombustible floor construction or to subflooring.

   (c)   When the subflooring and the structural elements are of fire-retardant treated wood, the space between the floor construction and the subflooring need not be filled.

(Prior code §  62-10.3)

15-8-490 Heavy timber construction.

   (a)   In buildings of heavy timber construction, all wood finished flooring and subflooring shall be applied directly to the floor construction or may be attached to sleepers of combustible materials provided that the space between the floor construction and the finished flooring is solidly filled with noncombustible materials.

   (b)   Combustible composition flooring not exceeding one-half inch in thickness may be applied directly to the floor construction or to subflooring.

   (c)   When the subflooring and the structural elements are of fire-retardant wood, the space between the floor construction and the subflooring need not be filled.

(Prior code §  62-10.4)

15-8-500 Stairways and exitways.

   In stairways required by Section 15-8-490 to be of noncombustible construction, finish flooring of combustible materials shall not exceed one-sixth inch in thickness.

(Prior code §  62-10.5)

15-8-510 Roof structures.

   Except aerial supports, not exceeding 12 feet in height, all roof structures hereafter placed above the roof of any building within the fire limits, or above the roof of any building exceeding 55 feet in height, shall be constructed of noncombustible materials and shall be supported by construction of noncombustible materials, except the walking surface of a rooftop deck may be of combustible materials meeting the requirements for Class A roof coverings if constructed above a roof of noncombustible material and supported by construction of noncombustible material. Such structures shall also comply with the special requirements of Sections 15-8-520 to 15-8-560, inclusive.

(Prior code § 62-11; Amend Coun. J. 3-29-17, p. 45477, § 5)

15-8-520 Skylights and monitors.

   (a)   Sashes and frames of skylights which are inclined more than 30 degrees from the vertical shall be constructed of noncombustible materials, except, as provided by the building commissioner, in buildings where acid fumes deleterious to metal are incidental to the use of the building.

   (b)   All skylights, except in greenhouses, shall be glazed with wired glass having no single pane exceeding 720 square inches in area or 48 inches in any dimension.

   (c)   Walls of skylights and monitors shall be of construction not less fire-resistant than required for the roof on which they are erected; provided, however, the walls which extend more than ten feet above the roof shall be constructed of noncombustible materials.

(Prior code § 62-11.1; Amend Coun. J. 9-13-89, p. 4604; Amend Coun. J. 3-5-03, p. 104990, § 42; Amend Coun. J. 11-13-07, p. 14999, Art. II, § 1)

15-8-530 Penthouses.

   (a)   A penthouse is hereby defined as an enclosed space located on a roof for the housing of a stairway or equipment used in the operation of a building such as tanks, fans or elevator machinery, but containing no habitable or storage space.

   (b)   Penthouses occupying an aggregate area exceeding one-third of the roof area shall be considered a story of the building and shall be subject to all applicable requirements of this Code.

   (c)   Walls of penthouses located less than five feet from the exterior walls of the building shall provide fire resistance as required for the exterior wall. Walls of penthouses located five feet or more from the exterior wall of a building, except in buildings of Types II, IV-A and IV-B construction, shall provide fire resistance of not less than one hour.

   (d)   Roofs of penthouses shall provide fire resistance as required for the roof construction on which the penthouse is located.

(Prior code §  62-11.2)