(a) Whenever the Building Commissioner finds any dwelling, structure or premises, or any improved real estate or any part thereof, to be in violation of Section 1409.98(a), the Commissioner may give or cause to be given or delivered or mailed to the owner, agent or operator of such structure or premises a written notice stating the violation(s) therein. Such notice shall order the owner, agent, or operator to repair or improve the structure or premises within a stated reasonable time, but not less than ten (10) days. Delivery may be effected by the Commissioner or his agent leaving said notice at the address of the owner, agent or operator. Such delivery or mailing shall be deemed legal service of notice.