Next Question: Vertical to horizontal 1/4 bend

[Markos]

Markos you might have a senario that allows that type venting the way you describe .
clean outs that need extended should use drainage fittings 707.6 not trying to pick at it just wanting to help you pass , I will tell you a lot of inspectors wont say a word about either of these.

Pick away. You won’t offend me at all!

 

[Tuttles Revenge]

Venting horizontally under the flood level is common and accepted practice in seattle. No inspector will blink at it so long as the entire vent under the flood level is drainage fittings and sloped. Anywhere that 2 fixtures combine needs to be 2" minimum. The 2x1.5fixture cross in any configuration is what your inspector will expect to see whether is formed or using bushings. We don't ever run any 1.5" drains except for trap arms or in rare cases where structural conditions dictate.

I'm not clear on that toilet vent area.. The pic with you holding a WYE branching off in the vertical position. If that is venting the toilet, you'll need to have the WYE on the horizontal with the branch tanken off the top half of the pipe (known as the invert) then with drainage fittings and slope up to your venting location.

 

[Sponsor]

 

[Markos]

Venting horizontally under the flood level is common and accepted practice in seattle. No inspector will blink at it so long as the entire vent under the flood level is drainage fittings and sloped. Anywhere that 2 fixtures combine needs to be 2" minimum. The 2x1.5fixture cross in any configuration is what your inspector will expect to see whether is formed or using bushings. We don't ever run any 1.5" drains except for trap arms or in rare cases where structural conditions dictate.

Thanks! I had no intention of swapping out the 2” fixture, it’s just that Fergusons has a 1.5x1.5x2” also with a 1.5” vent. It is perfect but I already have a 2x2x2x2 with adapters. I’m using 2” everywhere else. The only reason the vanity drains are 1.5 is because technically I can’t drill large enough holes in a structural 2x6 wall. It is my understanding that the outer diameter of 2” ABS is 2.374”, and 40% of a 5.5” 2x6 is 2.2”. Either way, that is the route I went but it is the only
load bearing wall that needs horizontal 2”.

I'm not clear on that toilet vent area.. The pic with you holding a WYE branching off in the vertical position. If that is venting the toilet, you'll need to have the WYE on the horizontal with the branch tanken off the top half of the pipe (known as the invert) then with drainage fittings and slope up to your venting location.

Sorry that isn’t in okay as of is. The piece with my hand in it is an optional route of that horizontal toilet vent was a problem. It is more than 6’ away from the toilet though. Given your feedback as well as feedback from another plumber, I will stick with my existing horizontal vent that over 45 degrees above the toilet drain. I do have structural limitations.

 

[Markos]

Updated video of toilet /shower/ vanity / laundry joining to a 2” common vent. I don’t have any outstanding questions but would love any feedback that you have.

FYI - I do intend to leave all of my cleanouts accessible. They will all be out of site.

 

[Markos]