For each sanitary building sewer, at least one three-inch vent stack (or stack vent) carried full size through the roof shall be installed as provided in part 4715.2330. A vent stack or main vent shall be installed with a soil or waste stack whenever individual vents, relief vents, or branch vents are required for stacks of three or more branch intervals.
For stacks of three or four branch intervals in height, all main vents or vent stacks shall connect full size at their base to the main soil or waste stack below, through, or not more than 18 inches above the lowest fixture branch.
For stacks of five or more branch intervals in height, a main vent or vent stack shall connect full size with the soil or waste stack it serves, with a wye and one-eighth bend below the lowest fixture branch connected to such soil or waste stack, or at a point approved by the administrative authority.
Each such soil or waste stack, and vent stack shall be similarly cross-connected with a yoke vent at intervals of not more than five branch intervals as described in part 4715.2640.
As provided in part 4715.2360, soil and waste stacks offset at an angle of more than 45 degrees from the vertical, that receive the discharge of fixtures four or more branch intervals or stories above the offset, shall have a yoke vent installed (as per part 4715.2640) at the base of the upper stack section.
Where stack vents and vent stacks are connected into a vent header, such connections shall be made at the tops of the stacks. The vent header shall connect to a vent extension through the roof.
|DIAMETER OF VENT IN INCHES|
d. f. u.
|MAXIMUM DEVELOPED LENGTH OF VENT, IN FEET|
|Diameter of Vent, in Inches|
|Fixture Units connected in d.f.u.||Maximum Developed Length of Vent, in Feet|
*Except 6 fixture unit fixtures.
ul -- Unlimited length.
np -- Not permitted.
May 14, 2012
Copyright © 2012 by the Office of the Revisor of Statutes, State of Minnesota. All rights reserved.