1.   No land shall be occupied or used, and no building hereafter erected or structurally altered shall be occupied or used in whole or in part for any purpose whatsoever, until a certificate is issued by the Zoning Administrator, stating that the building and use comply with the provisions of this chapter.

   2.   No change of use shall be made in any building or part thereof, now or hereafter erected or structurally altered, without a permit being issued therefor by the Zoning Administrator. No permit shall be issued to make a change unless the changes are in conformity with the provisions of this chapter.

   3.   Nothing in this part shall prevent the continuance of a nonconforming use as hereinbefore authorized, unless a discontinuance is necessary for the safety of life or property.

   4.   Certificates for zoning compliance shall be applied for coincidentally with the application for a building permit, and shall be issued within 10 days after the lawful erection or alteration of the building is completed. A record of all certificates shall be kept on file in the office of the Zoning Administrator, and copies shall be furnished on request to any person having a proprietary or tenancy interest in the building affected.

   5.   No permit for excavation for, or the erection or alteration of any building shall be issued before the application has been made for certificate of zoning compliance, and no building or premises shall be occupied until that certificate and permit is issued.