Any legal nonconforming use may be continued, except as set forth in §§ 68-12, 68-341.IF and 68-401; provided, however, that a legal nonconforming use shall not be changed unless changed to a conforming use. A legal nonconforming use, if changed to a conforming use, may not be thereafter changed to any nonconforming use.

The substantial discontinuance of any nonconforming use for a period of one year or more terminates such nonconforming use of a structure or premises, and thereafter said structure or premises shall not be used, except in conformity with provisions of this ordinance.

No building which has been damaged by fire or other causes to the extent of more than 50% of physical structure, as determined by the Commissioner of Planning and Development, or his designee, exclusive of foundations, shall be repaired, rebuilt or used except in conformity with the provisions of this ordinance.

Notwithstanding the foregoing provisions, no junkyard may continue as a nonconforming use for more than three years after the effective date of this amendment unless such use is made conforming by a change of zoning and a special permit granted by the Town Board.

(Reserved)[1]

The subdivision of any parcel(s) on which a legal nonconforming use(s) exists terminates such legal nonconforming use of a structure or premises, and, thereafter, said structure or premises shall not be used except in conformity with the provisions of the ordinance. However, this subsection shall not apply to the merger of parcels improved with principal structures if the subdivision shall restore the parcels and structures to the identical dimensions and densities which existed prior to the merger.

Merger of nonconforming lots. If at any time a nonconforming lot shall be held in the same ownership as one or more adjoining parcels, the lot shall lose its status as a nonconforming lot, except to the extent that the lot created by the merger of the adjoining parcels remains nonconforming with respect to one or more dimensional regulations of the district in which it is situated

A building arranged, designed or devoted to a nonconforming use at the time of the passage of this ordinance may not be reconstructed or structurally altered to an extent exceeding 25% of the ground area of that specific building, unless the use of said building is changed to a conforming use. The aggregate ground area of any additional nonconforming structures shall not be considered in this calculation.

A nonconforming use of land may not be extended in the aggregate more than 25% of the area occupied at the time of the passage of this ordinance.

No legal nonconforming use within a building may be expanded to more than 25% of the existing floor area occupied by the nonconforming use.

No extension of a nonconforming use may be made pursuant to the foregoing provisions of this section except after the granting of a special exception by the Board of Appeals in accordance with the provisions of § 68-415A of the Code of the Town of Islip.

This section shall not apply to existing structures that maintain a certificate of occupancy or certificate of compliance, provided they are being used for the permitted uses of the district within which they are located. Any addition or alteration to a structure in this category shall be subject to the dimensional requirements of the district in which it is located or shall apply for any necessary area variances from the Zoning Board of Appeals.

This section shall not apply to existing structures on substandard lots that maintain a certificate of occupancy or certificate of compliance, provided they are being used for the permitted uses of the district within which they are located. Any addition or alteration to a structure in this category shall be subject to the dimensional requirements of the district in which it is located or shall apply for any necessary area variances from the Zoning Board of Appeals.

Parcels being used for the permitted uses of the district but existing in a nonconforming location on a property will be allowed to expand or modify without variance provided the following conditions are met:

An applicant must send due notice of said application to the owner or owners of real property within 200 feet of the subject property. The notice must be mailed by certified mail, return receipt requested. Upon the day of the hearing, said receipt must be submitted to the Board, along with a copy of a Tax Map showing the premises and all premises within 200 feet.

Upon confirmation by the Board of any legal non-conforming use, a Building Inspector or other persons charged with the issuance of certificates of occupancy and/or certificates of compliance shall issue said document with an endorsement specifying the legal nonconforming use, and said document shall constitute presumptive use in any action or proceeding brought under this ordinance.

Upon proof satisfactory to the Board of Appeals after due public hearing, a structure, or additions thereto, which is intended to contain a permitted use only may be erected on any lot separately owned at the time of its rezoning to its current zoning district which does not meet the width and area requirements for said district, provided that the width and area requirements of the amended Zoning Ordinance were met prior to such rezoning, and further provided that all other requirements of the amended Zoning Ordinance associated with that district are met.

Proof of single and separate ownership shall be submitted to the Board of Appeals in the form of a recognized title company on a form prescribed by the Board, accompanied by a chain of title of the subject property and all contiguous property and also a survey prepared by a licensed surveyor identifying the contiguous lot numbers and/or properties.

Single and separately owned parcels may be merged with adjacent single and separate parcels to create larger parcels which more closely conform to the zoning requirements. In accordance with this policy, single and separate parcels located between adjacent single and separate parcels may be split and merged with the adjacent single and separate parcels. In order to encourage the merger of adjacent parcels to create larger parcels, the owner of a parcel of land which is in single and separate ownership may also merge an adjacent parcel that is not in single and separate ownership with the subject parcel, provided that the parcel not in single and separate ownership was a separate tax parcel on April 11, 1928.