In the A-P zone:
A. A structure originally designed as a residence, or as an accessory to a residence, may be used for a business or professional use under the conditions as provided for in chapter 18.156, article VI of this title.
B. No business or professional building shall be erected, constructed or established on the same lot together with a building originally designed as a residence.
C. All uses, except parking and loading, shall be conducted within a completely enclosed building.
D. Alleys may be required by the commission. (Ord. 1000 § 21.10, 1955)