All permits issued under this chapter shall expire by limitation 6 months after the date of issuance, if the work authorized by the permit has not been commenced. If, after commencement, the work is discontinued for a period of 12 months, the permit therefor shall immediately expire. No work authorized by any permit which has expired shall thereafter be performed, until a new permit therefor has been secured.
(G.S. § 160A-418) Penalty, see § 10.99