Individual vents to wet vent during remodel

[ajvpb]

Newbie DIY'ing this and want to make sure I understand how the different pieces of code go together. There will be dumb questions ahead so thanks for your patience with another guy stumbling through this.

In Utah which is using IPC.

Tub and shower drain are currently individually vented and connect to the waste line where the 2" pipe goes vertical down into the sewer pipe. Individual vents come through the floor of the bathroom at a 45 and then go up the exterior wall. Want to eliminate them to have a unobstructed floor to remodel on.

1) 912.3 says the maximum DFU for a 2" pipe is 4. Do my lav sinks count towards that DFU measurement?

2)909.1 is distance of trap from vent. That measurement is from the trap to where it joins the wet vent, correct? In other words, not back to the green line in my drawing where its a dry vent?

Thank you!!

 

[tamosius]

would help if you draw in some other color what you are trying to eliminate. My gut feeling is that you should keep the existing vents.

 

[Sponsor]

 

[Tuttles Revenge]

What you have drawn is a Horizontal Wet Venting (HWV) system and drawn correctly. I'm not familiar with the sizing of IPC code, but the structure of the system is good. Is there a toilet combining with all of this? Is it downstream? Is it separately vented?

Looks to me from the sizing chart that you would need 2-1/2"min (read 3") drain where the tub connects. And not sure what they expect for cleanouts. It says that at a horizontal offset of greater than 45* you need a cleanout at that offset. Not sure if you need one at the lavs.. I would. I think that the trap of the lav can serve as a cleanout and the downstream 1 size larger piping too. Not sure how IPC deals with the 3" downstream at the tub.. if that needs its own cleanout for the larger size.

rant on -- I wonder when industry will catch up and start producing 2-1/2" PVC and ABS pipe and fittings? Or when the code will catch up and realize those have basically been eliminated due to the fact that nobody wants to stock and store 1-1/4 or 2-1/2" pipe and fittings. -rant off

 

[wwhitney]

Looks to me from the sizing chart that you would need 2-1/2"min (read 3") drain where the tub connects.

Only if the lav/tub/shower drain is being used to wet vent another fixture downstream. If the wet vent ends at the tub, the branch drain can stay 2" after the tub.

rant on -- I wonder when industry will catch up and start producing 2-1/2" PVC and ABS pipe and fittings?

The inclusion of the 2-1/2" trade size in the plumbing codes primarily matters if a code section calls for something to be "more than one pipe size larger" than a 2" pipe. With 2-1/2" trade size as a recognized size, 3" pipe is in fact "two pipe sizes" larger than 2".

Cheers, Wayne

 

[Jeff H Young]

on commercial Sure nice not screwing with 1 1/2" and actually snapping 3 inch your constantly adjusting the cutters to that all the way tight or all the way loose for the chainsnaps. Id almost prefer no 3 inch if not for my weak arms and beat up body. 2 , 4 and 6 inch is easier to work with 5 inch pipe sucks too just another bastard size