All permits issued by this department shall expire by limitation and become null and void if the work authorized by the permit is not commenced within (6) six months; or if construction or work is suspended for a period of (6) six months at a time; or if the work as authorized by such permit is abandoned at any time after the work is commenced. Before such work can begin again, a new permit shall first be secured for the unfinished portion of the work.

No refund of the permit price shall be allowed or applied to another permit.