All main, soil, waste or vent pipes must be
cast iron, galvanized wrought iron, galvanized steel, brass or Type
K or L copper tubing. Vent piping may be copper, Type DWV.
Necessary offsets above the highest fixture
branch must not be made at an angle of less than 45° to the horizontal.
Soil and waste pipes must have proper Y- and
TY-branches for all fixture connections.
No connections to lead branches for water closets
or slop sinks will be permitted, except required branch vent.
Branch soil and waste pipe must have a fall
of at least 1/4 inch per foot.
Short TY-branches will be permitted on vertical
lines only. Long 1/4 bends and long TY's are permitted. Short 1/4
bends, double hubs, common offsets, bends and saddles are prohibited.
At the foot of a stack where connection is made to drain, short one-quarter
bends and short T's are prohibited.
The diameter of all riser lines in plumbing
systems shall be not less than 3/4 inch where there is more than one
fixture on the second floor.
Separate stopcocks or valves, so located as
to be accessible at all times, shall be placed at the foot of each
riser and in all buildings other than residence buildings occupied
exclusively by one or two families or having not more than 15 sleeping
rooms, on each branch line from the riser for each isolated fixture
or each group of fixtures, such as bathroom fixtures, kitchen fixtures,
etc.; except that only one stopcock or valve shall be required for
the fixtures contained in any one apartment, suite, store or loft
occupied by one tenant when all the fixtures contained in each such
apartment, suite, store or loft are supplied from one branch line.
Diameters of branches to any fixtures must not
be less than 1/2 inch except when used to supply water closets, cisterns
or lavatories. When the material used is lead, brass or copper pipe,
the minimum diameter may be 3/8 inch. Branches for flush valves for
water closets must not be less than one inch in diameter, and for
urinals, not less than 1/2 inch in diameter.
All risers and branches must be properly fastened.