Fences (including retaining walls) shall be constructed of new or suitable used material, shall conform with the methods of construction pursuant to the requirements of the Uniform Building Code as adopted by reference and modified by Chapter 15.04 of this code, and shall be maintained in a state of good repair. Any dilapidated, dangerous or unsightly fence or retaining wall shall be repaired or removed. Temporary materials shall not be permitted as a fencing material.