In order to promote healthful living conditions and to stabilize the value and character of residential areas, dwelling units shall be erected, altered, moved, maintained or occupied only in accordance with the minimum floor area requirements set forth below:
(a) Attached One-Family Dwelling:
(1) The minimum total floor area per dwelling unit shall be 1,000 square feet.
(2) The minimum ground floor area per dwelling unit shall be 750 square feet.
(b) Multi-Family Dwelling: The minimum floor area per dwelling unit shall be 650 square feet plus 200 square feet for every bedroom over one.