What did I get myself into - Plumbing with NO venting?

[Reach4]

Thanks for your input. So your saying the bathroom sink and shower drain should come into the main DOWN stream of the toilet?

He is saying that the lavatory and shower should join each other before joining the toilet flow. Then the kitchen stuff come in after the bathroom stuff has joined.

 

[wwhitney]

If by "main" you mean 3" pipe (or maybe it's 4"), then there is a difference between the sink/shower joining the 3" upstream of the WC or downstream of the WC. But if it joins upstream of the WC, that just means you made part of the sink/shower branch 3", when 2" would have been sufficient.

Cheers, Wayne

 

[Sponsor]

 

[Cabin Country]

OK, I get what your saying.

So I'm learning a lot and greatly appreciate it. One thing I'm not clear on is the importance of the timing of the connection of the kitchen. Why does the kitchen need to connect after the bathroom drains? Is it because of the venting issue?

 

[wwhitney]

Yes, wet venting is limited to bathroom groups, so kitchen drainage is not allowed in the wet vent. If each fixture were individually dry vented, the order of drain connections wouldn't matter.

Cheers, Wayne

 

[Cabin Country]

HA! This is starting to make sense. If I can get a vertical cleanout installed, what would you recommend I use to make the turn from vertical into the 4" horizontal main, combo wye to help guide the snake if needed? I think I could tie into the end of the 4" main and turn it up into the wall cavity, kind of where the kitchen comes into the 4" main now.

 

[Tuttles Revenge]

I drew it to comply with UPC wet venting requirements. In horizontal wet venting per UPC, the toilet wants to be last or most downstream and the kitchen connected after the bathroom group. The bathroom sink will still be the primary vent for the entire structure and should be a minimum of 2" (UPC) and since there are other structures with venting presumably meeting cross sectional venting, this system only needs to meet its minimum vent for the fixtures.

This would help down the road if and when the property is sold.. that the plumbing complies with some form of consensus based plumbing code.

 

[wwhitney]

If I can get a vertical cleanout installed, what would you recommend I use to make the turn from vertical into the 4" horizontal main, combo wye to help guide the snake if needed? I think I could tie into the end of the 4" main and turn it up into the wall cavity, kind of where the kitchen comes into the 4" main now.

You're talking about an upper terminus cleanout for the 4" main? 4" pipe won't fit in a 2x4 wall, but it would fit in a 2x6 wall. If you wanted access via a floor plug, you'd just turn up the horizontal main with a LT90.

For wall access, you'd turn it up into the 2x6 wall; then I'm not sure what would be best within the wall. You could obviously use a large enough access panel, and just a cleanout plug at the top of the vertical, but maybe there an option that's better looking or provides better access.

Cheers, Wayne

 

[Cabin Country]

I drew it to comply with UPC wet venting requirements. In horizontal wet venting per UPC, the toilet wants to be last or most downstream and the kitchen connected after the bathroom group.

But in your drawing, the toilet is not the most downstream, but rather the bath sink/shower are. Unless I'm misunderstanding?

 

[Cabin Country]

You're talking about an upper terminus cleanout for the 4" main? 4" pipe won't fit in a 2x4 wall, but it would fit in a 2x6 wall. If you wanted access via a floor plug, you'd just turn up the horizontal main with a LT90.

For wall access, you'd turn it up into the 2x6 wall; then I'm not sure what would be best within the wall. You could obviously use a large enough access panel, and just a cleanout plug at the top of the vertical, but maybe there an option that's better looking or provides better access.

Cheers, Wayne

Bingo, the LT90 answers it. I do have a 2x6 wall behind the toilet, I'll figure something out on how to terminate it weather it's up into the wall or at floor level like you mentioned.

 

[wwhitney]

But in your drawing, the toilet is not the most downstream, but rather the bath sink/shower are. Unless I'm misunderstanding?

In Tuttle's drawing, the WC is downstream most in terms of the flow of the bathroom fixtures, which is what matters for wet venting. It's not downstream most on the 4" main, but as per the previous comments, that doesn't matter.

Cheers, Wayne

 

[Cabin Country]

Owww I get how your looking at that. Thanks everyone for your time!