All roofs and paved areas, yards, courts and
courtyards shall be drained into the stormwater sewerage system but
not into sewers intended for sewage only. Where there is no sewer
accessible, such connections shall be discharged into the public gutter,
unless otherwise permitted by the proper authorities, and in such
case need not be trapped.
When placed within the walls of any building
or run in an inner or interior court or ventilating pipe shaft, all
conductors or roof leaders shall be constructed of cast iron or galvanized
wrought iron or steel pipe.
Where an existing sheet metal conductor pipe
within the walls of any building becomes defective, such conductor
shall be replaced by one which conforms to this article.
Conductor pipes shall not be used as soil, waste
or vent pipes, nor shall any soil, waste or vent pipes be used as
conductors. House or intercepting traps and fresh air inlets are prohibited
in connection with house drains.
Overflow pipes from cisterns, supply tanks,
expansion tanks and drip pans shall connect only indirectly with any
house sewer, house drain or soil, waste or vent pipe.
Where subsoil drains are placed under the cellar
floor or used to encircle the outer walls of a building, the same
shall be made of open-jointed drain tile or earthenware pipe, not
less than four inches in diameter, and shall be properly trapped and
protected against back pressure by an automatic back pressure valve
accessibly located before entering the storm sewer or drain. They
may discharge through a cellar drain.