Roof signs shall be constructed entirely of metal or other approved noncombustible material except as provided for in Sections H 106.1.1 and H107.1. Provisions shall be made for electric grounding of metallic parts. Where combustible materials are permitted in letters or other ornamental features, wiring and tubing shall be kept free and insulated therefrom. Roof signs shall be so constructed as to leave a clear space of not less than 6 feet (1829 mm) between the roof level and the lowest part of the sign and shall have at least 5 feet (1524 mm) clearance between the vertical supports thereof. No portion of any roof sign structure shall project beyond an exterior wall.
Exception: Signs on flat roofs with every part of the roof accessible.
A roof sign having a solid surface shall not exceed, at any point, a height of 24 feet (7315 mm) measured from the roof surface.
Open roof signs in which the uniform open area is not less than 40 percent of total gross area shall not exceed a height of 75 feet (22860 mm) on buildings of Type 1 or Type 2 construction. On buildings of other construction types, the height shall not exceed 40 feet (12192 mm). Such signs shall be thoroughly secured to the building upon which they are installed, erected or constructed by iron, metal anchors, bolts, supports, chains, stranded cables, steel rods or braces and they shall be maintained in good condition.
A closed roof sign shall not be erected to a height greater than 50 feet (15240 mm) above the roof of buildings of Type 1 or Type 2 construction or more than 35 feet (10668 mm) above the roof of buildings of Type 3, 4 or 5 construction.