For any Tier II site, the City Planning Commission may grant special permits to allow single-family semi-detached residences in R1 and R2 Districts, single-family attached residences in R1, R2 and R3-1 Districts or two-family attached residences in R3-1 Districts.

As a condition for granting such special permits, the minimum required lot area of the underlying district shall not be reduced, and the aggregate width of street walls of a building, or a number of buildings separated by party walls, shall not exceed 100 feet.

In order to grant such special permits, the Commission shall find that:

(a)        development is not feasible without such modifications, or that the requested modification will permit a development, enlargement or site alteration that better satisfies the purposes of this Chapter;

(b)        the change of housing type requested constitutes the most effective method of preserving the existing topography and vegetation;

(c)        the preservation of existing topography and vegetation requires the permitted development to be concentrated, to the extent feasible, in the remaining portion of the tract;

(d)        for such concentration of development, better standards of privacy and usable open space can be and are achieved under the development plan by inclusion of the proposed building type;

(e)        such modification is the least modification required to achieve the purpose for which it is granted;

(f)        the proposed street or private road system for the development is so located as to draw a minimum of vehicular traffic to and through streets in the adjacent area;

(g)        the siting of the building or buildings will not adversely affect adjacent properties by impairing privacy or access of light and air; and

(h)        the existing topography and vegetation and the proposed planting effectively screen all attached one-family residences from the lot lines along the development perimeter.

The Commission may impose appropriate conditions or safeguards, such as special landscaping requirements, to minimize any adverse effects on the character of the surrounding area.

All developments, enlargements or site alterations that require a special permit pursuant to this Section shall also be subject to the provisions of Sections 119-33 (Special Erosion and Sedimentation Prevention Requirements for Certain Authorizations and Special Permits) and 119-34 (Special Submission Requirements for Certain Authorizations and Special Permits).