Chapter 4 - Non-Complying Buildings
Except as otherwise provided in Section 54-313, a non-complying building or other structure may be enlarged or converted, provided that no enlargement or conversion may be made which would either create a new non-compliance or increase the degree of non-compliance of a building or other structure or any portion thereof.
If a building or portion of a building contains rooming units, such rooming units may be converted to dwelling units in accordance with the provisions of Section 15-111 (Number of permitted dwelling units).
(a) In R4 Districts, except R4-1, R4A and R4B Districts, and in R5 Districts other than R5B Districts, for an existing single- or two-family residence with a non-complying front yard, an enlargement involving a vertical extension of existing building walls facing such non-complying front yard is permitted, provided the following conditions are met:
(1) the portion of the building which is being vertically extended complies with the height and setback regulations specified for the district in which it is located; and
(2) the non-complying front yard where the building wall is being vertically extended is at least 10 feet in depth.
Notwithstanding the above, the provisions of this paragraph (a) shall also be applicable in R4A Districts in lower density growth management areas.
(b) In all districts, for an existing single- or two-family residence with a non-complying side yard, an enlargement involving a vertical extension of existing building walls facing such non-complying side yard is permitted, provided the following conditions are met:
(1) the portion of the building which is being vertically extended complies with the height and setback regulations applicable to an R3-2 District;
(2) the non-complying side yard where the building wall is being vertically extended is at least three feet in width and the minimum distance between such building wall and the nearest building wall or vertical prolongation thereof on an adjoining zoning lot across the common side lot line is eight feet;
(3) the enlarged building does not contain more than two dwelling units;
(4) there is no encroachment on the existing non-complying side yard, except as set forth in this Section; and
(5) the enlargement does not otherwise result in the creation of a new non-compliance or in an increase in the degree of non-compliance.
Notwithstanding the provisions set forth in paragraphs (a)(1) and (b)(1) of this Section, when an existing building has added exterior wall thickness pursuant to Section 23-44 (Permitted Obstructions in Required Yards or Rear Yard Equivalents), such vertical extensions may align with the location of the finished exterior building wall of the existing building.
In R6, R7 or R8 Districts, for any substantial rehabilitation of one or more non-complying multiple dwellings which were in existence prior to December 15, 1961, the City Planning Commission may authorize the existing open space on the zoning lot to be reduced by not more than five percent and the existing building floor area on such zoning lot to be increased by not more than five percent, if the Commission finds that such modification of the applicable bulk regulations as set forth in Section 54-31 will result in an improved apartment design with adequate access of light and air and an improved circulation system. In the Special Clinton District, such authorizations may apply to complying multiple dwellings and may include a five percent increase in lot coverage and floor area. The Commission, in making the findings above may round out the floor area or lot coverage increase to the nearest percent.
No increase in the existing density and apartment floor area shall be permitted for such buildings.
For the purposes of this Section, buildings that abutted one another on a single zoning lot on the date of such damage or destruction shall be considered a single building.
If a non-complying building or other structure is damaged or destroyed by any means, including any demolition as set forth in this Section, to the extent of 75 percent or more of its total floor area, such building may be reconstructed only in accordance with the applicable district bulk regulations, except in the case of a one- or two-family residence, such residence may be reconstructed provided that such reconstruction shall not create a new non-compliance nor increase the pre-existing degree of non-compliance with the applicable bulk regulations. If the extent of such damage or destruction is less than 75 percent, a non-complying building may be reconstructed provided that such reconstruction shall not create a new non-compliance nor increase the pre-existing degree of non-compliance with the applicable bulk regulations.
In addition, the alteration of such existing building resulting in both the removal of more than 75 percent of the floor area and more than 25 percent of the perimeter walls of such existing building, and the replacement of any portion thereof, shall be considered a development for the purposes of the provisions set forth in Section 11-23 (Demolition and Replacement).
In the event that any demolition, damage or destruction of an existing building other than one- or two-family residences produces an unsafe condition requiring a Department of Buildings order or permit for further demolition of floor area to remove or rectify the unsafe condition, and the aggregate floor area demolished, damaged or destroyed including that ordered or permitted by the Department of Buildings constitutes 75 percent or more of the total floor area of such building, then such building may be reconstructed only in accordance with the applicable district bulk regulations.
In any case where the applicant alleges that floor area is an inappropriate measure of the extent of damage or destruction, and elects to substitute reconstruction costs for floor area, an application may be made to the Board of Standards and Appeals to determine the extent of the damage or destruction. Such a building may be reconstructed as provided in Section 54-41 (Permitted Reconstruction), substituting the ratio which the cost of reconstructing the damaged or destroyed portion of such building bears to the cost of reconstructing the entire building, for the percentage of total floor area. In determining reconstruction costs, the cost of land shall be excluded.