Mich. Admin. Code R. 408.30534 - [Effective until 8/29/2025] Venting

Rule 534. Section P3105.1 is amended and section 3105.4 and figure P3105.4 are added to the code and figure N3 in appendix N of the code is amended to read as follows:

P3105.1. Distance of trap from vent. Each fixture trap shall have a protecting vent located so that the slope and the developed length in the fixture drain from the trap weir to the vent fitting are within the requirements in table P3105.1 of the code.

P3105.4. Vertical leg for waste fixture drains. A vertical leg (see figure P3105.4) is permitted within a fixture drain of a waste fixture in accordance with the following criteria:

(1) Minimum trap diameter shall be in accordance with table P3201.7 of the code.

(2) The diameter of section A shall be equal to the diameter of the trap.

(3) The length of section A shall not be less than 8 inches (2032 mm) and in accordance with table P3105.1 of the code.

(4) The diameter of section B shall be 1 pipe size larger than the diameter of Section A.

(5) The length of section B shall not be more than 36 inches (9144 mm).

(6) The diameter of section C shall be 1 pipe size larger than the diameter of section B.

(7) The total length of section A and section C shall not exceed the distance allowed in table P3105.1 of the code.

(8) Bends shall be the diameter of the largest connected section.

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FIGURE P3105.4

VERTICAL LEG FIXTURE DRAIN SCHEMATIC

Figure N3. Typical liorizontal wet venting.

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Notes

Mich. Admin. Code R. 408.30534

2001 AACS; 2004 AACS.; 2008 AACS; 2010 AACS