The lawful use of open land for storage purposes or for advertising signs and bulletin boards which does not conform to the provisions of this chapter shall be discontinued within two (2) years from the date of approval of this chapter, and the use of land for storage purposes or for signs and bulletin boards which becomes nonconforming by reason of a subsequent change in this chapter shall also be discontinued within two (2) years of the date of the change.

The lawful use of a building existing at the time of the effective date of this chapter may be continued although such use does not conform to the provisions thereof. A nonconforming use of a building may be changed to another nonconforming use of the same or of a more restricted classification. Whenever a nonconforming use has been changed to a more restricted use or to a conforming use, such use shall not thereafter be changed to a less restricted use.

Whenever the use of a building becomes nonconforming through a change in the zoning ordinance or district boundaries, such use may be continued and if no structural alterations are made it may be changed to another nonconforming use of the same or of a more restricted classification.

In the event that a nonconforming use of any building or premises is discontinued or its normal operation stopped for a period of two (2) years, the use of the same shall thereafter conform to the use permitted in the district in which it is located.

No existing building or premises devoted to a use not permitted by this chapter in the district in which such building or premises is located, except when required to do so by law or order, shall be enlarged, extended, reconstructed or structurally altered, unless such use is changed to a use permitted in the district in which such building or premises is located.

When a building, the use of which does not conform to the provisions of this chapter, is damaged by fire, explosion, act of God, or the public enemy, to the extent of more than sixty percent (60%) of its fair market value, it shall not be restored except in conformity with the district regulations of the district in which the building is situated, provided, however, that such building may be restored if the board of adjustment finds some compelling public necessity requiring the continuance of the nonconforming use.