The board shall decide all applications and appeals within 30 days after the final hearing thereon. A copy of the board's decision shall be transmitted to the applicant or appellant, and to the planning commission by the zoning administrator. Such decision shall be binding upon the zoning administrator and observed by him and he shall incorporate the terms and conditions of the same in the permit to the applicant or appellant whenever a permit is authorized by the board. A decision of the board shall not become final until the expiration of five days from the date such decision is made unless the board shall find the immediate effect of such decision is necessary for the preservation of property of personal rights and shall so certify of the record.