When repairs are made to any existing lateral connection constructed on vitrified tile pipe, PVC or material other than extra-heavy pipe of cast iron as described in §
222-26 hereof and where such repairs necessitate the excavating of the line from the house connection to the curb or in the public streets or highways or in both, said vitrified tile or PVC pipe or pipe consisting of materials other than extra-heavy iron as provided for in this article shall be removed, and the extra-heavy cast-iron pipe as described in §
222-26 hereof shall be substituted therefor.