Where the designated Residence District is an R6 through R12 District, the applicable street wall location provisions of this Section shall apply. Such provisions shall apply to the portion of a street wall located below the maximum base height and before the required setback as set forth in Section 123-652 as applicable. 

1. Percentage-based rules
   
   At least 70 percent of the aggregate width of street walls shall be located within eight feet of the street line and shall extend to at least the minimum base height specified in Section 123-652 or the height of the building, whichever is less. Up to 30 percent of the aggregate width of street walls may be recessed beyond eight feet of the street line, provided that any such recesses deeper than 10 feet along a wide street or 15 feet along a narrow street are located within an outer court.
   
   However, where the street walls surrounding the subject building are located on a block with a prevailing street wall frontage that is located further from the street line than the applicable provisions of this paragraph, the line-up provisions of paragraph (a) of Section 23-431 may be applied.
2. Modifications for large zoning lots
   
   Notwithstanding the provisions of paragraphs (a) of this Section, for street walls on buildings on a zoning lot that has a lot area of at least 40,000 square feet or that occupy an entire block, at least 70 percent of the aggregate width of street walls shall be located within 15 feet of the street line and extend to at least the minimum base height specified in Section 123-652, or the height of the building, whichever is less.
3. Articulation allowances
   
   In all districts, and along all frontages, street wall articulation, including, but not limited to, window recesses and structural expression on the building facade, shall be permitted to project or recess beyond the street wall locations established in paragraphs (a) or (b) of this Section, provided that such articulation does not exceed a depth or projection of 12 inches. In addition, to accommodate other forms of street wall articulation, such as bay windows, and facade recesses, up to 50 percent of the aggregate width of street wall, at any level, may recess or project beyond such street wall location provisions of this Section, provided that no such recess or projection exceeds a depth of three feet, as measured perpendicular to the street wall, or portion thereof. No projection shall extend beyond the street line, except where encroachments into the public right-of-way are permitted by the New York City Administrative Code.