(1) Use Regulations. The specific uses permitted in this district shall be the erection, construction, alteration, or use of buildings and/or land for:

(a) The uses permitted in "R-10" Residential Districts, subject to all qualifications imposed on such uses;

(2) Area Regulations.

(a) General Provision. Irrespective of the size of the property concerned, every main building and/or use thereon shall have its lot lines indicated, and all buildings shall be erected, constructed, altered or used in accordance with the area provisions herein contained as applied to the lot so indicated.

(b) Lot Width and Area.

(.1) Single-family and duplex dwellings: The minimum lot width shall be 18 feet and the minimum lot area shall be 1,620 square feet.

(.2) Multiple dwellings: The minimum lot width shall be 18 feet for a one, two or three-story dwelling, 24 feet for a four-story dwelling, and 30 feet for a dwelling of five stories, and the minimum lot area shall be 540 square feet for every family contained therein.

(.3) Buildings other than dwellings: The minimum lot width shall be 35 feet and the minimum lot area shall be 3,150 square feet.

(c) Occupied Area and Floor Area.

(.1) Single-family and duplex dwellings: Not more than 50% of the area of the lot shall be occupied by buildings.
(.2) Multiple dwellings and buildings other than dwellings: Not more than 50% of the area of the lot shall be occupied by buildings nor shall the gross floor area of the building exceed an area equal to 150% of the area of the lot.

(d) Open Area. The open area shall be not less than 50% of the lot area and shall consist of at least the required minimum front and rear yards in all cases, plus such other open courts and/or side yards as shall be required to equal an area not less than the total open area above required.

(e) Building Set-back Line. The building set-back line shall be 15 feet from all street lines.

(f) Yards.

(.1) Front. The minimum depth of a front yard shall be the depth required between a street line and the building set-back line, as herein specified.

(.2) Side. When one or more side yards are used, each shall have the following minimum required widths; provided, that every building located on a corner lot shall have the building set-back on the intersecting street adjudged a side yard, which shall be not less than the set-back required:

(.a) Single-family dwellings and duplex dwellings: five feet;

(.b) Multiple dwellings and buildings other than dwellings: eight feet.

(.3) Rear.

(.a) Single-family dwellings and duplex dwellings: The minimum depth of a rear yard shall be 20 feet;

(.b) Multiple dwellings and buildings other than dwellings: The minimum depth of a rear yard shall be 30 feet.

(.4) Courts.

(.a) Open courts, when used, except between the wings of the same building, shall have a minimum width of not less than the required minimum width of a side yard.

(.b) Inner courts and open courts between the wings of the same building, when used, shall be governed by the provisions of § 14-231(1) of this Title.

(3) Height Regulations.

(a) Single-family and duplex dwellings: The maximum height of a building shall be 35 feet above the average ground level at the base of the building, but in no case over three stories;

(b) Multiple dwellings: The maximum height of a building shall be 50 feet above the average ground level at the base of the building, but in no case over five stories;

(c) Buildings other than dwellings: The permitted height of nonresidential buildings shall be 35 feet except that one foot of additional height may be added for each foot the building sets back from all lot lines; provided, however, that the maximum height of any such building shall be 60 feet (subject to the provisions of § 14-231(2)).

(4) Application to Existing Dwellings. Any dwelling in this district may be converted to contain a greater number of families under the following provisions:

(a) If said dwelling, as converted, will meet the Use, Area, and Height Regulations as set forth above;

(b) If, in lieu of meeting the Use, Area, and Height Regulations as set forth above, the following provisions are complied with:

(.1) In order to convert from a single-family dwelling to a duplex dwelling, a dwelling shall either:

(.a) Have a rear yard with a minimum depth of 20 feet; or

(.b) Comply with the requirements of subparagraphs (.2) and (.3) below.

(.2) For the number of families in a dwelling to be increased, the majority of the floors of said dwelling must have an area of at least 700 square feet per floor and the total floor area must be a minimum of 1,600 square feet. In such a case, additional families may be added as follows:

(.3) In addition, families shall not be added unless there is provided at least 300 square feet of yard space (including any area used for open-air parking), for each family contained in the building.

(c) Any construction or alteration made in connection with any conversion permitted in this paragraph shall conform to the area and height regulations of this district; provided, that where necessary, legally required fire escapes may exceed such regulations.

(5) Off-street Parking. See § 14-1400 of this Title.