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[Happycamper]

I originally mapped out option 2 seen in the image below. I'm thinking option 1 is better/faster. (Option 1 vent goes to roof from sink. Are either/both of these ok? Thanks

OPTION 1

OPTION 2

 

[Sylvan]

2 is better ... Don't forget to trap the shower

 

[Sponsor]

 

[wwhitney]

Option 1 is a standard wet arrangement for the IPC (which does not require the WC to be last on the wet vent). Presumably you have a trap at the shower, and the trap arm from the trap outlet to the 3" branch drain needs to fall no more than one inside diameter while still falling at 1/4" per foot.

In Option 2 you added some dry vents; the dry vent takeoffs have to be vertical (i.e. at most 45 degrees off plumb) and stay vertical until above the flood rim level of any fixtures upstream of the takeoffs. I can't tell from your drawing if that requirement is satisfied. But you've added the dry vent takeoffs to the branch drain, so Option 2 still relies on wet venting. If you want to dry vent each fixture, then the dry vent takeoff needs to be on the fixture drain, i.e. before it joins the branch drain, not after.

Cheers, Wayne

 

[Reach4]

I'm thinking option 1 is better/faster. (Option 1 vent goes to roof from sink. Are either/both of these ok?

Both OK under IPC.
Lav and shower need traps that are not shown.

Except for the sanitary tee for the lavatory, the waste-joining connections should be via wyes or combos.

 

[Happycamper]

Thanks everyone for the comments. I added the traps into the images below. Does option 2 look correct for dry vents now? If so, do both look correct now before I decide between the two?

Is dry venting that much better? Trying to decide if I want to do the extra work of extra vents.

Why would WC need to be last in some codes?

Also, it's hard to see, but both options have a cleanout near the sink in the 2 inch drain.
Thanks


OPTION 1

OPTION 2

 

[Sylvan]

Option 2

 

[wwhitney]

Thanks everyone for the comments. I added the traps into the images below. Does option 2 look correct for dry vents now?

No. The dry vent takeoff has to be between the trap (or WC) and the wye where the drain joins the 3" branch.

If so, do both look correct now before I decide between the two?

Otherwise, yes.

The jog just above where the 2" sink drain turns horizontal, where you have (2) 45s, then a 45 and a wye, any chance you could do that as just a 45 and a wye? Or do you need that short vertical segment to avoid an obstacle? A minor possible optimization.

No opinion on the other questions.

Cheers, Wayne

 

[Happycamper]

No. The dry vent takeoff has to be between the trap (or WC) and the wye where the drain joins the 3" branch.
Cheers, Wayne

Ahhhh, gotcha.

The jog just above where the 2" sink drain turns horizontal, where you have (2) 45s, then a 45 and a wye, any chance you could do that as just a 45 and a wye? Or do you need that short vertical segment to avoid an obstacle? A minor possible optimization.
Cheers, Wayne

Yeah, there is an obstacle, but I'll see if I can get around it with less 45s.

Option 2

Thanks Sylvan

 

[wwhitney]

Let me reiterate that in Option 2, "the dry vent takeoffs have to be vertical (i.e. at most 45 degrees off plumb) and stay vertical until above the flood rim level of" the fixture vented. Often that's hard for a WC while keeping the vent hidden in the floor and walls. So that's one advantage of wet venting as in Option 1.

Yeah, there is an obstacle, but I'll see if I can get around it with less 45s.

No biggie, at first I thought you were using (2) 90s for the jog, which would be less desirable, but then I looked more closely before posting.

Cheers, Wayne

 

[Happycamper]

Let me reiterate that in Option 2, "the dry vent takeoffs have to be vertical (i.e. at most 45 degrees off plumb) and stay vertical until above the flood rim level of" the fixture vented. Often that's hard for a WC while keeping the vent hidden in the floor and walls. So that's one advantage of wet venting as in Option 1.

Thanks Wayne. Huge help.
Been trying to figure out how to add those in for dry vents and its very difficult for me to figure out how to route, for the exact reasons you are stating. Shower pan etc get in the way.

 

[wwhitney]

Yes, often you have to choose the route of the trap arm based on how to get near a wall for the dry vent, rather than the most direct path to the branch drain.

Cheers, Wayne

 

[Reach4]

Under IPC, most people would go with option 1.

 

[Happycamper]

Yes, often you have to choose the route of the trap arm based on how to get near a wall for the dry vent, rather than the most direct path to the branch drain.

I made another attempt at dry vents. I attached two different views to see it better. Is this correct?
If this is correct, I think I know why most chose option 1 if available. So much less work it seems.

View 1

View 2

 

[Happycamper]

Under IPC, most people would go with option 1.

I think I see why haha. So much work to do the dry vents. Probably better in the end, but so much work. Thanks Reach!

 

[wwhitney]

I made another attempt at dry vents. I attached two different views to see it better. Is this correct?

Yes, it's correct, although I think you can vent the shower and WC with fewer bends in each case. Assuming the rendering is to scale and there isn't some hidden obstruction.

E.g. for the WC, you can point the closet bend directly at the final 3" branch on the left, unless that would hit the shower drain in the shower pan. If it would, you can jog it one way or the other by turning it 22.5 or 45 degrees, and then use a 22.5 degree or 45 degree elbow to turn back to perpendicular to the final 3" branch on the left.

For the shower, you can keep the U-bend pointed towards the vent wall, but turn the outlet elbow 90 degrees to run run parallel to the vent wall (and not pointed at the WC drain). Then your vent takeoff is a combo or san-tee on the its back (allowed under the IPC), with the side inlet pointed up but rolled 45 degrees off vertical. That should let the dry vent rise at 45 degrees off plumb to get under the vent wall before breaking the plane of the finish floor. Then a 45 degree bend turns the vent plumb into the wall.

Is this over a crawl space, or perhaps with a floor system with I-joists or 2x12s? Otherwise it often pays to minimize 3" drains perpendicular to the joists.

Cheers, Wayne

 

[Happycamper]

Thanks Wayne.
We have some property in some mountains out away from civilization. I'm building a small 8x8 outdoor bathroom to make it more comfortable. (I have 4 daughters). It's just a seasonal place as it can get snowed in.

I was able to have somebody install septic who pulled a permit etc... But, being out away from everything, it's not easy to get a plumber out there so trying to do these drains myself.

The green line going to the septic tank is not very deep where it terminates. The guy also put it very close to a rock wall so I can't go straight down in unless I move the green line, but am hesitant right now. (Clearly I don't know what I'm doing with plumbing haha) Below are some images of what I'm building. (one with option 1 and one with option 2)

Thinking vent would only go through roof about a foot or so and hope no problems if I do option 1 since it can get some snow on it.

Option 1

Option 2

 

[Happycamper]

Oh, since we don't have a well drilled yet, I'd just have water delivered in a tank and run a hose down from the driveway (maybe 8-10 foot drop) and connect in to fill the toilet and to the sink. Not ideal but what I have to work with for now so my family has somewhere to clean up.

 

[Jeff H Young]

a small unpermitted shack , I think I'd just go with option 1

 

[Happycamper]

Thanks everyone

 

[Happycamper]

Sorry guys. Another question. I decided to do option 1 like some suggested. I did have to change things up as purchased a different shower pan than what I had planned to use as well as trying to incorporate what Wayne suggested with minimizing turns etc...

On the picture below, I brought out the toilet trap arm with a 45 degree bend in it. Is this ok to do? Will I see problems?

Also, in trying to follow the rules with vent to trap max distance, I'm assuming it's to the wye's on the shower and toilet and not all the way back to the sink where the wet vent starts at the sani tee correct?

Thanks again. I'm understanding so much more than when I started.