A building or structure or part or appurtenance thereof or a construction condition found to be hazardous to life, limb or health, upon order of the building commissioner or enacting authority, shall be corrected, repaired, replaced, vacated, demolished or removed and the premises or work restored to or put in a safe condition within thirty (30) days after such a finding has been made in writing, written notice of the finding and order has been given to the owner or his agent or the contractor, and except in emergencies, a hearing on the order has been held before the building commissioner. (Ord. 71-O-168, 4-1-1971)