79-401 - Special permit for development over streets LAST AMENDED 2/2/2011 In a #large-scale community facility development# containing #schools#, hospitals or functionally related facilities in R6 or R7-1 Districts, in C1 or C2 Districts mapped within such #Residence Districts#, when the air space above a #narrow street# or portion thereof is closed and demapped, the City Planning Commission may, by special permit, allow the demapped air space to be considered as part of the adjoining #zoning lots# constituting a single #zoning lot#, and may allow within such demapped air space the #development# or #enlargement# of a #building# which is a necessary expansion of an existing #school#, hospital or functionally related facility located on adjoining #zoning lots#. As a condition for granting a permit for such #building#, or portion thereof, within the demapped air space, the Commission shall find: (a) that there is a Master Plan for institutional development which demonstrates that the #building# over the #street# is necessary to avoid or minimize demolition of existing facilities, or #buildings designed for residential use#, and expansion on existing #zoning lots# owned by the #community facility# is not feasible to meet its expansion needs; (b) that the location of such #building#, or portion thereof, will not impair the existing residential character of the area; (c) that such #building#, or portion thereof, utilizes only unused #floor area# from adjoining #zoning lots# and no #floor area# credit is received from the demapped air space, and such #building# complies with the off-street parking and loading requirements of the underlying district or districts; (d) that such #building#, or portion thereof, is contained entirely within the buildable area of the air space plane as defined in this Section, conforms with the height and setback regulations set forth in this Section, is no more than 200 feet in length and is the only such #building# on a #block# front; (e) that such #building#, or portion thereof, links the #zoning lots# across the #street#, in the same ownership, with adequate clearance above the #street# bed, and there is no intrusion on the existing #street#, including column supports; (f) that all #street# frontages of the #zoning lots# under such #building#, or portion thereof, are provided with fenestration or natural light along at least 75 percent of such frontages, and such #street# frontages when #developed# with #uses# other than open area, contain only #uses# requiring human occupancy such as amusement, education, dining, shopping and other similar #uses# permitted by the underlying district regulations; that the main entrance for principal pedestrian access to the #development# is located along the #street# frontages under such #building# and that no storage rooms, mechanical equipment rooms, parking and loading facilities or curb cuts are located along such #street# frontage unless authorized by the Commission; (g) that a satisfactory lighting and ventilation plan consistent with current environmental standards is provided for the #development#; and (h) that an additional amount of #open space# for public use at #street# level, linked with the pedestrian circulation system of the area, equivalent to the #street# area covered by such #building#, is provided within 1,000 feet of the #building# and such #open space# maintained as usable public area in the ownership of the applicant. #Curb levels# of the pre-existing #zoning lots# shall not be affected by the closing and demapping of air space over such #street#. The Commission may impose additional conditions and safeguards to improve the quality of the development and minimize adverse effects on the character of the surrounding area. For the purposes of paragraph (d) of this Section: Air space plane is a plane above a #narrow street# located at the same elevation as the lower limiting plane of a volume of #street# eliminated, discontinued and closed by the Board of Estimate, or its successors. The length "L1" of such air space plane is the length of the common lot frontage of two #zoning lots# opposite and across the #street# in the same ownership and its width is the width of the #narrow street# "SW" (See illustration of Required Setback for the Buildable Area). The buildable area "C" is the lower limiting plane of the volume of #street# eliminated, discontinued and closed by the Board of Estimate, or its successors, except that in no case shall the edge of the buildable area be closer to the edge of the air space plane by a distance equal to one half the #street# width "SW/2" (See illustration of Required Setback for the Buildable Area). REQUIRED SETBACK FOR THE BUILDABLE AREA The #building# over the #street# shall comply with the height and setback regulations of this Section and the buildable area shall be completely covered by such #building#, except that such #building# may be set back from the edge of the buildable area which traverses the #street# provided that such setback area is open and obstructed from the lowest level of the #street# to the sky. The #development# or #enlargement# of such #building# on the buildable area of the air space plane shall comply with the following #sky exposure plane# regulations (See illustration of Required Sky Exposure Plane): Height above #street# #Sky Exposure Plane# District bed (in feet) Slope over buildable area (expressed as a ratio of vertical distance to horizontal distance) Vertical Distance Horizontal Distance 60 2.7 to 1 R6 R7-1 C1 C2 REQUIRED SKY EXPOSURE PLANE The height of the vertical wall or any other portion of a #building# over the #street#, shall not penetrate the #sky exposure plane#. The #sky exposure plane# shall be measured from a point above the edge of the buildable area which traverses the #street#.