(1) General. The supports for all signs shall be placed in or upon private property and shall be securely built, constructed, and erected in conformance with the requirement of this title.
(2) Materials. Materials of construction for signs shall be of the quality and grade as specified for buildings in the building code.
In all signs, the materials and details of construction shall, in the absence of specified requirements, conform to the following:
(a) Structural steel shall be of such quality as to conform to standards of the building code. The thickness of sheet metal, when formed integrally with the display surface, shall be not less than No. 24 gauge. When not formed integrally with the display surface, the minimum thickness of the secondary members shall be not less than No. 12 gauge. The minimum thickness of hot-rolled steel members furnishing structural support for signs shall be of sufficient strength to support the loads imposed upon them. Steel pipes shall be of such quality as to conform to the building code. Steel members may be connected with one galvanized bolt provided the connection is adequate to transfer the stresses in the member;
(b) Anchors and supports for signs when of wood which are embedded in the soil, or in direct contact with, shall be pressure treated with an approved preservative before erection.
(c) No material, part, portion, or equipment shall be used in any sign that might become dangerous because of vibration, corrosion, disintegration, or any other reason.
(3) Restrictions on Combustible Materials. Freestanding signs may be constructed of any materials meeting the requirements of this title.
Wall signs, blade or projecting signs, and signs on awnings or canopies or marquees shall be constructed of incombustible materials, except as provided in subsection (4) of this section. No combustible materials other than approved plastics shall be used in the construction of electric signs.
(4) Nonstructural Trim. Nonstructural trim may be of wood, metal, approved plastic or any combination thereof.
(5) Anchorage. Members supporting unbraced signs shall be so proportioned that the bearing loads imposed on the soil in either direction, horizontal or vertical, shall not exceed the safe values. Braced signs shall be anchored to resist the specified wind or seismic load acting in any direction. Anchors and supports to the ground shall be designed for safe bearing load on the soil and for an effective resistance to pull-out amounting to a force 25 percent greater than the required resistance to overturning.
Signs supported by frames or posts rigidly attached to the base but not anchored into the ground shall be so proportioned that the weight and size of the base will be adequate to resist the wind pressure specified in PMC 17.30.010(1).
Signs attached to masonry, concrete, or steel shall be safely and securely fastened thereto by means of metal anchors, bolts, or approved expansion screws of sufficient size and anchorage to safely support the loads applied.
No wooden blocks or plugs or anchors with wood used in connection with screws or nails shall be considered proper anchorage, except in the case of signs attached to wood framing.
No anchor or support of any sign shall be connected to, or supported by, a parapet wall, unless such wall is designed in accordance with the requirements specified in the building code for parapet walls.
Cables, chains, wires or other flexible or loosely connected members shall not be considered as adequate fastening, except for cloth signs and banners.
No sign shall be erected within the City unless the same is securely affixed to a solid foundation or constructed so as to prevent the movement of the sign in a swinging motion.
(6) Sign Quality. All signs, and the copy thereon, visible from the street, shall be designed and constructed to reduce distraction to motorists, and the copy thereon shall be clear, legible, and compatible with other permitted signs within that zoning district.