No lot area, yard or other open space, or required off-street parking area existing on or after the effective date of the ordinance codified in this title shall be reduced in area, dimension or size below the minimum required by this title, nor shall any lot area, yard or other open space, or off-street parking area which is required by this title for one use, be used as the lot area, yard or other open space or off-street parking requirement for any other use.

A use specifically mentioned as allowed outright or by conditional use permit in one district is not allowed in another district unless that use is specifically mentioned as the allowed or conditional use in that district.