[1982 Code § 134-8.1B]
In a One- and Two-Family Residential Zone, no building or premises shall be used, and no building or part of a building shall be erected or altered, which is arranged, intended or designed to be used, in whole or in part, for any uses except the following:
a. Those uses permitted in the R-A One-Family Residential Zone.
b. A two-family dwelling, not to exceed one (1) such dwelling on each lot.