No sign shall hereafter be located, erected, moved, reconstructed, extended, enlarged, converted, or structurally altered without a building permit, except those signs excepted in § 255-81 and without being in conformity with the provisions of this chapter.
All signs are prohibited in all residential, agricultural, floodplain, public and semipublic, and natural resource preservation districts except the following:
A. 
Agricultural signs pertaining to the products at the agricultural premises, not to exceed 30 square feet in area for any one farm.
B. 
Signs over show windows or doors of a nonconforming business establishment announcing, without display or elaboration, only the name and occupation of the proprietor and not to exceed two feet in height and 10 feet in length.
C. 
Real estate signs not to exceed eight square feet in area, which advertise the sale, rental or lease of the premises upon which said signs are temporarily located.
D. 
Name, occupational and warning signs, not to exceed two square feet, located on the premises.
E. 
Bulletin boards for public, charitable or religious institutions, not to exceed 16 square feet in area, located on the premises.
F. 
Memorial signs, tablets, names of buildings, and date of erection when cut into any masonry surface or when constructed of metal and affixed flat against a structure.
Signs are permitted in all commercial and manufacturing districts, subject to the following restrictions:
A. 
Wall signs placed against the exterior walls of buildings shall not extend more than six inches outside of a building's wall surface, shall not exceed 500 square feet in area for only one premises, and shall not exceed 20 feet in height above the mean center-line street grade.
B. 
Projecting signs fastened to, suspended from, or supported by structures shall not exceed 100 square feet in area for any one premises; shall not extend more than six feet into any required yard; shall not extend more than three feet into any public right-of-way; shall not be less than five feet from all side lot lines; shall not exceed a height of 23 feet above the mean center-line street grade; and shall be not less than 10 feet above the sidewalk nor 18 feet above a driveway or an alley.
C. 
Ground signs shall not exceed 20 feet in height above the mean center-line street grade, shall meet all yard requirements for the district in which they are located, and shall be limited to only one sign for each street frontage.
D. 
Roof signs shall not exceed 10 feet in height above the roof, shall meet all the yard and height requirements for the district in which they are located, and shall not exceed 300 square feet on all sides for any one premises.
E. 
Window signs shall be placed only on the inside of commercial buildings and shall not exceed 25% of the glass area of the pane upon which the sign is displayed.
F. 
Combinations of any of the above signs shall meet all requirements for the individual signs.
No sign except those permitted in § 255-82 shall be permitted to face a residential district within 100 feet of such district boundary.
Signs shall not resemble, imitate or approximate the shape, size, signals or devices, form or color of railroad or traffic signs. Signs shall not obstruct or interfere with the effectiveness of railroad or traffic signs, signals or devices. No sign shall be erected, relocated or maintained so as to prevent free ingress to or egress from any door, window or fire escape; and no sign shall be attached to a standpipe or fire escape. No sign shall be placed so as to obstruct or interfere with traffic visibility, nor be lighted in such a way as to cause glare or impair driver visibility, upon public ways.
Signs lawfully existing at the time of the adoption or amendment of this chapter may be continued although the use, size or location does not conform with the provisions of this chapter. However, such sign shall be deemed a nonconforming use or structure, and the provisions of § 255-20 shall apply.