Notwithstanding the provisions of CMC 10.04.010 and 10.04.020, the provisions of CMC 10.04.020 shall not be applicable to the use of the streets therein listed by a vehicle when it is necessary for a vehicle to travel over such streets for the purpose of delivering materials to be used in the actual and bona fide conduct of a business located on such street or repair, alteration, remodeling, or construction of any building or structure located upon such streets and for which a building permit has previously been obtained and is in full force and effect. The provisions of CMC 10.04.020 shall not be effective until appropriate signs have been erected. (Ord. 481 § 1. 2002 Code § 8-3).