A. 
The lawful nonconforming use of a structure or land, including but not limited to fences, parking and zoning setbacks, existing at the time of the adoption or amendment of this chapter may be continued although the use does not conform to the provisions of this chapter. However, only that portion of the land in actual use may be so continued, and the structure may not be extended, enlarged, reconstructed, substituted, moved or structurally altered except when required to do so by law or order or so as to comply with the provisions of this chapter.
B. 
If no structural alterations are made, a nonconforming use of a building may be changed to any use permitted in the same use district as that in which the use existing is permitted according to the provisions of this chapter, provided that when a use district is changed, any existing nonconforming use in such changed district may be continued or changed to a use permitted in the same use district as that in which the existing use is permitted, provided that all other regulations governing the new use are complied with.
C. 
Substitution of new equipment may be permitted by the Board of Appeals if such equipment will reduce the incompatibility of the nonconforming use with the neighboring uses.
A. 
Termination. If such nonconforming use is discontinued or terminated for a period of 12 months, any future use of the structure or land shall conform to the provisions of this chapter.
B. 
Building destroyed by fire. Where a building located in a district restricted against its use has been destroyed by fire or other calamity to the extent of not more than 50% of its assessed value the same may be rebuilt, but where such a building is destroyed to the extent of more than 50% of its assessed value, a permit may be granted for its reconstruction within 12 months from the date of such fire or other calamity, except that any public utility located in a restricted district shall be permitted to rebuild, alter or enlarge in any business or industrial district as the interest of the public demands.
A lawful nonconforming structure existing at the time of the adoption or amendment of this chapter may be continued although its size or location does not conform to the lot width, lot area, yard, height, parking and loading, and access provisions of this chapter. However, it shall not be extended, enlarged, reconstructed, moved or structurally altered except when required to do so by law or order or so as to comply with the provisions of this chapter.
Once a nonconforming use or structure has been changed to conform, it shall not revert back to a nonconforming use or structure. Once the Board of Appeals has permitted the substitution of a more restrictive nonconforming use for an existing nonconforming use, the substituted use shall lose its status as a legal nonconforming use and become subject to all the conditions required by the Board of Appeals.
Unless otherwise provided, there shall be a setback line of not less than that required by the appropriate district, provided that:
A. 
Where 40% or more of the frontage is occupied with buildings having an average setback line of more, or of less, than 25 feet, the setback line in any vacant interior lot in such frontage shall be established at the point of intersection of its center line, drawn from the front street line, and a line connecting the nearest points on the setback lines of the next existing buildings on each side of such vacant lot.
B. 
On any corner lot less than 60 feet wide and of record at the time of the original passage of this chapter, where reversed frontage exists, the setback on the side street shall be not less than 50% of the setback required on the lot in the rear, and no accessory building shall project beyond the setback line of the lot in the rear, provided further that in no case shall the buildable width of such corner lot be reduced to less than 24 feet.