506.3.2 Minimum frontage distance.

To qualify for an area factor increase based on frontage, the public way or open space adjacent to the building perimeter shall have a minimum distance (W) of 20 feet (6096 mm) measured at right angles from the building face to any of the following:

   1.   The closest interior tax lot line.

   2.   The entire width of a street, alley or public way.

   3.   The exterior face of an adjacent building on the same tax lot.

Where the value of W is greater than 30 feet (9144 mm), a value of 30 feet (9144 mm) shall be used in calculating the building area increase based on frontage, regardless of the actual width of the public way or open space. Where the value of W varies along the perimeter of the building, the calculation performed in accordance with Equation 5-5 shall be based on the weighted average calculated in accordance with Equation 5-4.

W = (L1 × w1 + L2 × w2 + L3 × w3 …)/F      (Equation 5-4)

where:

   W   =   (Width: weighted average) = Calculated width of public way or open space (feet).

   Ln    =   Length of a portion of the exterior perimeter wall.

   wn    =   Width (≥ 20 feet) of a public way or open space associated with that portion of the exterior perimeter wall.

   F   =   Building perimeter that fronts on a public way or open space having a width of 20 feet (6096 mm) or more.

   Exception: Where a building meets the requirements of Section 507, as applicable, except for compliance with the minimum 60-foot (18 288 mm) public way or yard requirement, and the value of W is greater than 30 feet (9144 mm), the value of W shall not exceed 60 feet (18 288 mm).

506.3.3 Amount of increase.

The area factor increase based on frontage shall be determined in accordance with Equation 5-5:

If = (F/P - 0.25) W/30      (Equation 5-5)

where:

   If   =   Area increase factor due to frontage.

   F   =   Building perimeter that fronts on a public way or open space having minimum distance of 20 feet (6096 mm).

   P   =   Perimeter of entire building (feet).

   W   =   Width of public way or open space (feet) in accordance with Section 506.3.2.

Section BC 507: Unlimited Area Buildings

507.1 General.

The area of buildings of the occupancies and configurations specified in Sections 507.1 through 507.18 shall not be limited, except that only one cellar or one basement shall be permissible.

507.1.1 Accessory occupancies.

Accessory occupancies shall be permitted in unlimited area buildings in accordance with the provisions of Section 508.2, otherwise the requirements of Sections 507.3 through 507.18 shall be applied, where applicable.