Copies of all ordinances for the establishment of the boundaries of any zone or district regulating or limiting the use, height, area, bulk and construction of buildings to be submitted to the city council shall, before the same are presented to the council, be first submitted by the city recorder to the planning commission for recommendation, and the said recorder shall immediately so notify the council, and said commission shall make its recommendation thereon in writing to the council; provided, that the planning commission shall first hold a public hearing at such time and place as may be directed by the council, and make a careful and appropriate investigation thereon; and thereafter, before final action shall be taken by the council on the location or design of any public building, bridge, stadium, park, parkway, boulevard, playground or public grounds, the same shall be submitted to the planning commission for its consideration and report. Unless the council definitely names a longer period for the return of a report specified herein, the approval of the planning commission to any matter referred to it in accordance with this chapter shall be deemed to have been given at the end of thirty (30) days after the receipt of the same in writing by its secretary, unless the planning commission shall submit a report thereon prior to that time. (1962 Code § 2-2-8)