1220.15   TIME LIMIT FOR PLAT APPROVAL.
   The Planning Commission shall approve, modify or disapprove a plat within sixty days after the submission thereof to it; otherwise such plat shall be deemed to have been approved, and a certificate to that effect shall be issued by the Planning Commission on demand; provided, however, that the applicant for the Planning Commission's approval may waive this requirement and consent to an extension of such period.
(1981 Code § 5.15)