Current through Register Vol. 50, No. 3, March 20, 2024
A. Horizontal Branches. A horizontal waste
branch meeting the following criteria shall effectively provide an exception to
the need for a revent pipe(s).
1. Provided:
a. the horizontal branch is full size
throughout its length;
b. each
fixture drain enters the horizontal branch via a wye and 1/8th bend or a
combination wye and 1/8th bend;
c.
the wastes are connected with a pitch of not more than 1/4 inch per foot (21 mm
per meter);
d. that a 2-inch "P"
trap shall be the minimum for tubs and showers;
e. the waste openings in the horizontal
branch shall not be less than 1 1/4 inches for lavatories and 1 1/2 inches for
a sink; and,
f. that one drinking
fountain shall be considered as one lavatory; then, without the use of
reventing:
i. one sink and one lavatory, or
one tub, or one shower, or three lavatories within 8 feet (2438 mm) developed
length of a main vented line may be installed on a 2-inch horizontal waste
branch; or,
ii. two lavatories
within 5 feet (1524 mm) developed length of a main vented line may be installed
on a 1 1/2-inch horizontal waste branch.
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Figure 923.A
B. Where Required. All fixtures discharging
downstream from a water closet shall be individually vented.
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Figure 923.B - Required Individual Vents
C. Limits of Fixture Units Above Bathtubs and
Water Closets. Up to a total of three fixture units may be placed on a soil or
waste stack on floors above the highest water closet or bathtub connection
without the use of a revent pipe(s) provided:
1. the soil or waste stack is not less than
3-inch diameter;
2. the total
fixture unit load on the stack does not exceed the limitations of Table 725.A.2
of this code;
3. the largest
fixture drain opening into the stack does not exceed the nominal diameter of
the trap of the fixture to be connected except as permitted in §923. A of this
code. Such opening for multiple fixture connections shall be limited to use on
one floor only;
4. each fixture
above the highest tub or water closet is no farther from the stack than
permitted in Table 913.A of this code; and,
5. all fixtures on lower floors are vented as
otherwise required by this Chapter.
AUTHORITY NOTE:
Promulgated in accordance with
R.S.
40:4(A)(7) and
R.S.
40:5(2)(3)(7)(9)(16)(17)(20).
