If, after building material of any kind is delivered on the site, actual construction work is not commenced within thirty days, or if, during the course of construction, work has been suspended for a like period, the permit shall be immediately revocable and notice to that effect shall be served on the contractor. This notice shall set forth that within five days the contractor shall furnish satisfactory proof that building operations are to be started or recommenced and carried out to completion. If the contractor shall fail to furnish such proof or, having furnished the same, fails to begin or resume work, then it shall be the further duty of the Building Commissioner to revoke such permit. Written notice of such revocation, signed by the Commissioner, shall be immediately served on the owner, agent, superintendent or contractor in charge of the work, or shall be posted on the premises, and no person shall perform any work in or about such structure, building or premises after the revocation of the permit and the posting of notice thereof.
(1986 Code § 1311.02)