No order of the Board of Zoning of Appeals that grants a variance shall be valid for a period longer than twelve months from the date of such order, unless all required zoning, building, occupancy and/or other appropriate permits and/or certificates are obtained within such period and the erection or alteration of a building is started, or the use is commenced, within such period.
(Ord. 186-91. Passed 10-15-92.)