Except as otherwise provided in this article and except for the application of the performance standards provided for industry, the lawful use of land or structures existing at the date of the adoption of this chapter may be continued although such use or structure does not conform to the regulations specified by this chapter for the zone in which such land or structure is located; provided, however, that no such nonconforming use or structure shall be enlarged, increased or changed nor shall any nonconforming use be extended to occupy a greater area of land or structure than that occupied by such use or structure at the date of the adoption of this chapter.

Anything herein to the contrary notwithstanding, where a residence in a residential zone is nonconforming because it fails to meet the minimum lot requirements and/or the minimum yard requirements set forth in the Schedule of Dimensional Requirements,[1] the residence may be added to, provided that such addition does not in itself encroach upon the minimum setbacks or height requirements or exceed the maximum lot coverage requirement (when added to the coverage of other buildings) set forth in the Schedule of Dimensional Requirements. Should the addition itself encroach upon the minimum setback or height requirements or exceed the maximum lot coverage requirements set forth in the Schedule of Dimensional Requirements, a variance shall be required. Where an improvement and/or addition triggers the enhanced side yard setback requirements pursuant to § 186-66, a variance shall be required where the setback is deficient, even when the improvement and/or addition is not located within such required side yard setback.

Whenever a new principal structure is proposed to be constructed on a nonconforming lot, variance approval from the appropriate land use board shall be required even if the proposed new structure conforms to the minimum requirements contained in the schedule of dimensional requirements.