The street wall of any building for the first two stories or 23 feet, whichever is greater, shall be located on the street line and extend the entire length of the street line of the zoning lot not occupied by existing buildings to remain. However, at the intersection of two street lines, the street wall may be located anywhere within an area bounded by the two street lines and lines parallel to, and 10 feet from each street line. No street wall shall be required along a street line bounding any portion of a zoning lot which is less than 25 feet in depth measured from the street line of a wide street.

For street walls above the level of the second story or 23 feet, whichever is greater, at least 50 percent of the aggregate length of the street walls shall be located on the street line. The remainder of the aggregate length of the mandatory street walls at each story may be recessed from the street line to a depth not exceeding 10 feet provided that the length of any such recess does not exceed 25 percent of the aggregate length of the street walls at each story.

The mandatory minimum height above curb level of a required street wall without setback shall be 60 feet on a wide street and 23 feet on a narrow street, or the height of the building, whichever is less. No setback shall be permitted on a narrow street below a height of 55 feet.

The maximum permitted height of a street wall at the street line without setback shall not exceed 100 feet above curb level and, above this height, no portion of a building or other structure shall penetrate a sky exposure plane commencing at 100 feet and rising over the zoning lot at a ratio of 1.5 to 1.0.

In addition, no portion of a building or other structure shall penetrate a rear sky exposure plane commencing at a height of 100 feet above curb level and at a distance of 100 feet from and parallel to the street line, and rising over the zoning lot at a ratio of 1.5 to 1.0 along wide streets and at a ratio of 1.0 to 1.0 along narrow streets.

However, energy infrastructure equipment and accessory mechanical equipment shall be permitted obstructions above such height limits, subject to the provisions of Section 33-42.