Florida Building Code Section 188.8.131.52
If work has commenced and the permit is revoked, becomes null and void, or expires because of lack of progress or abandonment, a new permit covering the proposed construction shall be obtained before proceeding with the work.
Florida Building Code Section 184.108.40.206
If a new permit is not obtained within 180 days from the date the initial permit became null and void, the building official is authorized to require that any work which has been commenced or completed be removed from the building site. Alternately, a new permit may be issued on application, providing the work in place and required to complete the structure meets all applicable regulations in effect at the time the initial permit became null and void and any regulations which may have become effective between the date of expiration and the date if issuance of the new permit.
The City of Miami Beach will send the owner and/or permit holder a courtesy notification in the mail within 30 days of the expiration of their permit informing them that their permit will expire. If the work that has commenced and is ready for inspection the applicant should request an inspection from the Building Department prior to the expiration of the permit. NOTE: Only a passing inspection will extend the permit an additional 180 days.
To close a permit all required inspections for both the master permit and any linked permits must be completed and approved.
If your permit is about to expire, and you know you will not be able to request and pass a required inspection prior to the expiration date, you can request a one-time extension. This extension can only be requested when the permit is still active and not expired. You will need to submit a Permit Application with the Permit Extension box checked in the Permit Request section. A minimum permit fee will be charged. Once a permit has expired it can only be extended with a renewal permit.
If your permit has expired and you have not completed all required inspections, you must first obtain a renewal permit to reopen the permit and then you can continue requesting all remaining inspections.