Above the maximum height of a front wall at the ** street line** as set forth in Section 81-262, a

**may only encroach beyond the**

*building***if it complies with the provisions of this Section and if the area of**

*half-setback line***equals or exceeds the area of**

*compensating recess***in**

*encroachment***and**

*Zones B***in accordance with the provisions of Section 81-264 (Encroachments and compensating recesses).**

*C*(a) Special limitations

No ** encroachment** beyond the

**shall be within 30 feet of a**

*half-setback line***. (See illustration of Prohibited and Allowed Encroachment Beyond Half-Setback Line)**

*side lot line*PROHIBITED AND ALLOWED ENCROACHMENT BEYOND

HALF-SETBACK LINE

(81-265a)

(b) General provisions

The length, depth, height and area of ** encroachments** along any

**frontage all contribute to a**

*street***impact on daylight access. In order to determine whether the depth of a**

*building's***into**

*building's encroachment***is justified, the length of the**

*Zone C***, measured parallel to the**

*encroachment***, and its height above**

*street line***must also be evaluated. The extent of**

*curb level***also must be considered in relation to the extent of the area of**

*encroachment***in the same**

*compensating recess***. The purpose of the length and height rule is to ensure, in the case of**

*street frontage zone***beyond the**

*encroachments***, that the closer a**

*half-setback line***comes to the**

*building***, the less will be the length of its**

*street line***, its height or both. (See illustration of Elements Analyzed)**

*encroachment*The elements comprising this analysis are represented by symbols and are as follows:

(1)

De | = | depth of |

D | depth of |

De (depth of ** encroachment**) means depth of

**beyond the**

*encroachment***. Depth of**

*setback line***is measured perpendicularly to the**

*encroachment***.**

*setback line*D (depth of ** setback line**) means depth of

**from the**

*setback line***or depth of**

*street line***from the**

*ten-foot setback line***, whichever depth is greater.**

*street line*(2)

Le | = | length of |

L | length of |

Le (length of ** encroachment**) means total length of

**outside the**

*encroachment***. Length of**

*half-setback line***is measured as the total length of the**

*encroachment***projections on the**

*encroachments'***.**

*street line*L (length of ** front lot line**) means the length of the

**along the particular**

*front lot line***. However, the length of the**

*street***for the purposes of this Section shall not exceed 300 feet, irrespective of the actual**

*front lot line***length.**

*lot line*(3)

Le | = | length of |

Lr | length of recess |

Le (length of ** encroachment**) as defined in paragraph (b)(2) of this Section.

Lr (length of recess) means total length of ** setback line** not encroached upon by a

**.**

*building*(4)

H | = | height of |

L | length of |

H (height of ** encroachment**) means the height of the

**above**

*encroachment***.**

*curb level*L (length of ** front lot line**) as defined in paragraph (2) of this Section.

(5)

Ar | = | area of |

Ae | area of |

Ar (area of ** compensating recess**) means area of

**in the particular**

*compensating recess***. Area of**

*street frontage zone***is calculated to a depth of 100 feet from the**

*compensating recess***.**

*street line*Ae (area of ** encroachment**) means area of

**beyond the**

*encroachment***. Area of**

*setback line***is calculated to a depth of 100 feet from the**

*encroachment***.**

*street line*Values for the elements in paragraphs (b)(1) through (b)(5) shall be found for each ** street frontage zone** on which there is any

**beyond the**

*encroachment***.**

*half-setback line*ELEMENTS ANALYZED

(81-265b)

The elements, weighted according to the effects on daylight access, are represented in the formulas and charts that control the depth, length and height of ** encroachments**, as set forth in paragraph (c) of this Section.

**of proposed**

*Encroachments***or**

*buildings***beyond the**

*enlargements***are permitted only if in compliance at every point with the formulas in paragraph (c) of this Section. Aside from this general requirement, specified points at which the length, depth, height and area rules shall be applied are presented in paragraphs (d) and (e) of this Section.**

*half-setback line*(c) ** Encroachment** limitations by Formulas 1 and 2

Where applicants elect to have their

**regulated by the formulas,**

*buildings***shall comply with both Formula 1 and Formula 2 as set forth in this paragraph. Elements of the formulas and the symbols by which they are represented are as set forth in paragraph (b) of this Section.**

*buildings*Formula 1: | Maximum | H | = | 5.5—4 | ( | De | ) | —2.5 | ( | Le | ) |

L | D | L |

Formula 2: | Minimum | Lr | = | L |

3.5 |

The maximum height of ** encroachment** (H) allowed by Formula 1 may be modified for certain conditions, as follows:

(1) For short frontages

For any frontage less than 200 feet in length, the maximum

H |

L |

found by applying Formula 1 may be increased by the following multiplier:

2 | — | L |

200 |

(2) For large areas of *compensating recess*

To the extent that the aggregate area of ** compensating recess** (Ar) exceeds the aggregate area of

**(Ae), the maximum**

*encroachment*( | H | ) |

L |

found by applying Formula 1 may be increased by the following multiplier:

1 | + | .067 Ar |

Ae |

For the purposes of this modification, the measurement of the area of ** compensating recess** (Ar) and the area of

**(Ae) in each particular**

*encroachment***shall be made on the**

*street frontage zone***at the height level for which**

*encroachment grid***beyond the**

*encroachments***are checked. The**

*half-setback line***shall include all**

*encroachment grid***. (Ar) shall include all areas of**

*street frontage zones***in the particular**

*compensating recess***, whether or not connected, and (Ae) shall include all**

*street frontage zone***in both**

*encroachments***and**

*Zone B***in the same**

*Zone C***, whether or not such**

*street frontage zone***are connected.**

*encroachments*(d) Measurement of *encroachments*

The points at which the formulas are applied will depend upon the shape and dimensions of the ** encroachments** beyond the

**and shall be in accordance with the provisions of this paragraph and paragraph (e) of this Section.**

*half-setback line*Where the

**along a single**

*encroachments***frontage are not connected outside the**

*street***, each**

*half-setback line***shall be measured separately in accordance with the provisions of paragraph (e). However, at any given height, where such non-contiguous**

*encroachment***occur, the**

*encroachments***shall be examined together, and the length of**

*encroachments***(Le) shall be the total of the (Le) for the individual**

*encroachment***. (See illustration of Non-contiguous**

*encroachments***)**

*Encroachments*NON-CONTIGUOUS ENCROACHMENTS

(81-265d)

(e) Heights and depths at which formulas are applied

Heights and depths at which the formulas shall be applied are set forth in this paragraph. In addition to meeting the requirements of paragraphs (e)(1) and (e)(2) of this Section, the applicant shall demonstrate that there is no height at which the proposed ** building** or

**fails to comply with the formulas in paragraph (c) of this Section.**

*enlargement*(1) Standard requirement where length of ** encroachment** is uniform

Where the length of the

**(Le) is uniform for the entire height of the**

*encroachment***(H) and the entire depth (De) at every height, the length, depth and height rules expressed in the formulas shall be applied only at the height where (De/D) is greatest and at the outermost edge of the**

*encroachment***. (See illustration of Uniform Length of**

*encroachment***)**

*Encroachment*UNIFORM LENGTH OF ENCROACHMENT

(81-265e1)

(2) Standard requirement where length of ** encroachment** is not uniform

Where the length of the

**(Le) is not uniform, the rules shall be applied at the height level where (De/D) is greatest and also at the height level where the length of**

*encroachment***(Le) is greatest. If the greatest length of**

*encroachment***is uniform for part of the**

*encroachment***height, the rules shall be applied at the highest level at which such greatest length of**

*building's***occurs. (See illustrations Where Length of**

*encroachment***Is Not Uniform).**

*Encroachment*If for a particular height level, the length of the

**(Le) varies with the depth of the**

*encroachment***(De), the largest (Le) of this**

*encroachment***shall be used together with the largest (De) in applying the rules as if the**

*encroachment***were of uniform length as provided in paragraph (e)(1) of this Section.**

*encroachment*WHERE LENGTH OF ENCROACHMENT IS NOT UNIFORM

(81-265e2)

(f) ** Encroachments** by existing

*buildings*When a

**contains an existing**

*zoning lot***which encroaches beyond a**

*building***or a**

*half-setback line***, an**

*ten-foot setback line***or**

*enlargement***on such**

*development***shall comply with the following provisions:**

*zoning lot*(1) Existing ** buildings** below specified heights

(i) Except as provided in paragraph (f)(1)(ii) of this Section, an existing ** building** not more than 120 feet in height shall not be considered in applying the length and height rules even though a portion of such

**encroaches beyond the**

*building***or**

*half-setback line***along a 60 foot wide**

*ten-foot setback line***and an existing**

*street***not more than 150 feet in height shall not be considered in applying the length and height rules even though a portion of such**

*building***encroaches beyond the**

*building***or**

*half-setback line***along a**

*ten-foot setback line***75 or more feet in width.**

*street*(ii) However, the area occupied by the existing ** building** shall be included in the calculation of (Ar/Ae) for the modification of Formula 1 allowed in the case of large areas of

**, as set forth in paragraph (c)(2) of this Section.**

*compensating recess*(2) Existing ** buildings** above specified heights

Where an existing

**more than 120 feet in height encroaches beyond the**

*building***or**

*half-setback line***along a 60-foot wide**

*ten-foot setback line***or where an existing**

*street***more than 150 feet in height encroaches beyond the**

*building***or**

*half-setback line***along a**

*ten-foot setback line***75 or more feet in width, the following provisions, in addition to those of paragraph (d)(3) of Section 81-264 (Encroachments and compensating recesses), shall apply:**

*street*(i) no new construction on the ** zoning lot** shall encroach beyond the

**along any**

*half-setback line***, and**

*street*(ii) the length and height rules of this Section shall not apply.