Where, at the effective date of adoption or amendment of this code, a lawful use of a lot or structure exists that is made no longer permissible under the terms of this chapter as enacted or amended, such use may be sold or otherwise transferred to other owners and may be continued as long as it remains otherwise lawful.

Unlawful use of land or buildings. An unlawful use of land or buildings existing at the time of adoption of this chapter shall remain illegal and unlawful subject to all of the provisions and penalties of this chapter, even if located in a district where such use is permitted under the terms of this chapter, unless such use meets all of the area and bulk regulations, off-street parking regulations and all other regulations applicable to that use for the district in which it is located.

No nonconforming use of a lot or structure shall be enlarged or increased or extended to occupy a greater area than was occupied at the effective date of adoption or amendment of this code, unless the Zoning Hearing Board, after public hearing, shall interpret that the enlargement or extension is necessary by the natural expansion and growth of the nonconforming use. Any such enlargement or expansion shall conform to the area, height and yard requirements of the zoning district in which it is located.

No nonconforming use shall be moved in whole or in part to any other portion of the lot occupied by such use at the effective date of adoption or amendment of this code.

Any nonconforming use may be extended throughout any part of a structure that was designed for such use at the time the use became nonconforming; however, a nonconforming use shall not be extended to occupy another structure, unless that structure was located on the same lot at the time the use became nonconforming and has not been relocated.

No residential structure that is a legal nonconforming use in any zoning district shall be altered to add additional dwelling units unless all of the area and bulk regulations, off-street parking provisions and all other regulations applicable thereto in the district are met with respect to proposed additional dwelling units.

The new nonconforming use shall be equal to or better than the existing nonconforming use. In determining whether the new use is equal to or better than the existing nonconforming use, the Zoning Hearing Board shall consider whether the new use is listed as an authorized permitted use, conditional use or use by special exception in the most restrictive zoning district that allows the existing nonconforming use. In addition, the Board shall consider the following:

The new use shall be in keeping with the character of the neighborhood in which it is located.

The new use shall conform to the off-street parking requirements of this code for the new use. In authorizing the new use, the Zoning Hearing Board may grant a parking exemption, utilizing the applicable criteria of this code.

The new use shall be subject to the area and bulk regulations of the district in which the new use is located.

The new use shall be subject to the buffer area requirements of this code for C Zoning District uses if the use is an authorized use in the C Zoning District.

The new use shall be subject to any applicable standards and criteria of the use, if the use is authorized as a conditional use or use by special exception in the most restrictive zoning district classification where such use is authorized.

When a nonconforming use is changed to a conforming use, the use thereafter shall not be changed to a nonconforming use.

Where a nonconforming use exists on a lot, a conforming use shall not be established on the same lot unless the nonconforming use is discontinued.

In the event that damage or destruction of a structure in which a nonconforming use is conducted involves 50% or less of the gross floor area of the structure, repairs or reconstruction may be undertaken, provided that such restoration is diligently and visibly pursued under a valid building permit within 18 months of the date of such damage or destruction.

In the event that a structure in which a nonconforming use is conducted is damaged or destroyed by fire or other means to an extent of more than 50% of the gross floor area of the structure, repairs or reconstruction to the original footprint may be authorized by the Zoning Officer. New construction or alteration of the existing footprint may be authorized as a use by special exception by the Zoning Hearing Board, with the following standards and criteria:

Structural alteration.

Nonconforming signs may be repaired or reconstructed, provided that no structural alterations are made that increase the gross surface area of the sign; however, nonconforming signs that are damaged or destroyed to an extent of more than 50% of the area of the structure at the time of destruction shall not be reconstructed except in conformity with the provisions of this chapter. Nonconforming signs that are damaged or destroyed to an extent of less than 50% of the area of the structure may be repaired or reconstructed, provided that such restoration is completed within 30 days of the damage or destruction.

Nonconforming signs may not be enlarged, added to or replaced by another nonconforming sign, use or structure, except that the interchange of poster panels shall be permitted.

Repair or maintenance. Nothing in this article shall be deemed to prevent the strengthening or restoring to a safe condition of any structure or part thereof declared to be unsafe by the Borough Building Inspector or any other official charged with protecting the safety of the public.

Any lot of record existing at the effective date of this chapter may be used for the erection of a one-unit dwelling, without a lot area or lot width variance, even though its lot area and width are less than the minimum required by this chapter; however, such dwelling shall comply with the front, rear and side yard, height and lot coverage standards of the zoning district wherein it is located.

Where structures exist on adjacent nonconforming lots of record that have front yards less than the minimum depth required, the minimum front yard for an adjacent undeveloped nonconforming lot of record shall be the average depth of the nonconforming front yards on the immediately adjacent developed nonconforming lots.

The owner of a nonconforming use shall make an application for registration of the nonconforming use, and upon presentation of documentation acceptable to the Zoning Officer that the use was lawfully in existence prior to the effective date of this chapter or any amendment that created the nonconformity, the Zoning Officer shall register the same on a map and by Allegheny County Assessor’s block and lot number as a legal nonconforming use.

In the course of administering this chapter and reviewing applications for zoning certificates or variances, the Zoning Officer shall register all nonconforming structures and nonconforming lots as they become known through the application process.