Meetings of the board of building appeals shall be held at the call of the chairman and at such other times as such board may determine. All hearings before such board shall be open to the public. The board shall keep minutes of its proceedings, showing the vote of each member upon every question, or if absent or failing to vote, indicating such facts, and shall also keep records of its recommendations and other official actions. Such minutes shall be public records. (M.C. 1963, § 8.803)