(a) Within the business and residential district no premises shall be constructed or erected which are intended, arranged or designed for use other than the following specified uses which shall conform to the following minimum standards set forth for each use class.
(b) Residential uses as are set forth in Section 1305.02.
(c) Office buildings, store buildings, post offices, banks, hospitals, schools, hotels, motels, motor courts, restaurants, bakery shops, theatres, garages, parking lots and other such buildings and businesses as may be permitted by the Planning and Zoning Commission and of which buildings there shall not be permitted unless the exterior walls are constructed of incombustible building materials and unless such building fronts on a public street. Mobile home camps may be permitted in Business and Residential Districts.
(d) No residence, apartment building or other efficiency apartment shall be constructed on the second floor of any building used primarily for business purposes unless the inside measurements of the living area of the unit is at least 400 square feet per unit, and unless each unit shall be provided with separate toilet and separate cooking facilities and is equipped with municipal water supply
(1960 Code 7-302.2)