Should my wet vent wye's be horizontal or rolled up?

[egonline]

Hello all,

I am a DIYer and I am redoing my primary bathroom, and I'm looking for advice/review of my plumbing plan to ensure I'm interpreting the code correctly.

I have a double lavatory (with a single p trap and drain), a water closet, and a shower drain in this bathroom group. Here is a sketch of my current plan:

I'm fairly certain this is wet vented properly (please correct me if I'm wrong), but my main concern is the orientation of the wye fittings. Should the LAV drain/wet vent connect (wye #2) to the main drain line horizontally, or should it be rolled up to ~45 degrees? same with the shower drain connection (wye #1) - horizontal or rolled up? This is all in a crawl space, and vertical height isn't a large concern.

I feel like I've seen conflicting information on this.
For example, this brochure referencing IPC 2018 shows a combination vent system very similar to this, with the LAV sink coming in from above, not horizontally (figure 3 below).

However the latest version of the Florida plumbing code that I can find (2020 IPC amended), it seems to call out that it should connect horizontally.

Any advice/insight into this distinction would be very helpful! Thanks in advance - I know I'm not a plumber, just a DIYer doing his best.

Evan

 

[tkpopeye]

Great questions; I am in pretty much the same situation as you. Still waiting to hear from someone about my question that I had posted yesterday. Good luck Evan!

 

[Sponsor]

 

[Jeff H Young]

Hello all,

I am a DIYer and I am redoing my primary bathroom, and I'm looking for advice/review of my plumbing plan to ensure I'm interpreting the code correctly.

I have a double lavatory (with a single p trap and drain), a water closet, and a shower drain in this bathroom group. Here is a sketch of my current plan:
View attachment 107119

I'm fairly certain this is wet vented properly (please correct me if I'm wrong), but my main concern is the orientation of the wye fittings. Should the LAV drain/wet vent connect (wye #2) to the main drain line horizontally, or should it be rolled up to ~45 degrees? same with the shower drain connection (wye #1) - horizontal or rolled up? This is all in a crawl space, and vertical height isn't a large concern.

I feel like I've seen conflicting information on this.
For example, this brochure referencing IPC 2018 shows a combination vent system very similar to this, with the LAV sink coming in from above, not horizontally (figure 3 below).
View attachment 107120

However the latest version of the Florida plumbing code that I can find (2020 IPC amended), it seems to call out that it should connect horizontally.

View attachment 107121

Any advice/insight into this distinction would be very helpful! Thanks in advance - I know I'm not a plumber, just a DIYer doing his best.

Evan

they should be flat but with 1/4in per ft fall

 

[wwhitney]

Angle of wye at (2) (wet venting lav coming in) doesn't matter for the IPC.

Angle of wye at (1) (shower being wet vented) is fine "flat", i.e. 1/4" per foot fall on the side inlet. The rule is the drop from the shower trap outlet to the edge of the 3" portion of the wye is limited to one pipe diameter (typically 2" for a shower, although the IPC allows 1-1/2"). So rolling it up a little is OK if the trap is close and you're not in danger of hitting the maximum drop, but there's no benefit to rolling it up, DWV-wise.

Cheers, Wayne