The R-1 single-family residential district is the most restrictive residential district. The principal use of land is for single-family dwellings and related recreational, religious and educational facilities normally required to provide an orderly and attractive residential area. These residential areas are intended to be defined and protected from the encroachment of uses which are not appropriate to residential environment. Stability of property values, attractiveness, order and efficiency are encouraged by providing for adequate light, air and open space for dwellings and related facilities and through consideration of the proper functional relationship of the different uses. (Prior code § 16-11)