302.1 Existing Buildings or Structures

Additions or alterations to any building or structure shall comply with the requirements of the Building Code of New York State for new construction. Additions or alterations shall not be made to an existing building or structure that will cause the existing building or structure to be in violation of any provisions of the Building Code of New York State. An existing building plus additions shall comply with the height and area provisions of the Building Code of New York State. Portions of the structure not altered and not affected by the alteration are not required to comply with the code requirements for a new structure. [B]

For buildings and structures in flood hazard areas established in Section 1612.3 of the Building Code of New York State , any additions, alterations or repairs that constitute substantial improvement of the existing structure, as defined in Section 1612.2 of the Building Code of New York State, shall comply with the flood design requirements for new construction and all aspects of the existing structure shall be brought into compliance with the requirements for new construction for flood design. [B]