Main Drain Line with branches

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PrecisionPlum

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Horizontal connections to Main Drain with Wyes with 45's
Vertical connection to laterals made with two 45's

Did I miss anything with this layout?

Code in this area is UPC.

1591150878678.png
 
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breplum

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Looks like you are trying for Horizontal wet venting. You can NOT use HWV when you have upstairs drain feeding that line. HWV is for bath groups on the same level only.
With HWV lavs and sinks are always vertically vented, no exceptions.
You should look up and print for references IPC commentary on the subject.
Nice rendering btw, what did you use to render?
 

PrecisionPlum

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Breplum,

The upper lever bathroom groups are VTR (Not previously shown), and some modifications made
to the diagram. Please see the attached.

My reference material may be out of date, but,
"HWV begins at the dry vent connect and extends downstream to the last fixture being wet vented."

The 4" drain can support all the DFUs at one time, if an event like that should ever happen.
HWV of the shown bathroom group is by the LAV AAV

The rendering:
The initial rendering was by hand with various PDF tools used for notes, arrows, and additional lines.

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breplum

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You seem to have full loading of the upstream "2" bath groups feeding the main drain, so, your drawing does not comply to my understanding of allowable design and function.
You would have to bypass that upstream plumbing for your new bath group and pick it up after the lower floor bath group, like where you have the Flow arrow.
Or if you want to keep the primary 4" line the way it is, just use standard UPC plumbing vents and forget HWV.
- Thus: assuming you know that AAVs need permanent access for servicing and replacement and are NOT to code in virually any district where I come from.
Keep the lav as is, add a 1-1/2" vent for the shower.
Add a 2" vent for the WC. Proven to work for generations.
btw, I have read published articles from plumbing engineers that you could vent most fixtures with 1" vents and the systems would work fine. But, nobody ever wants to take on code bodies.
Also, you can have up to 3 bathrooms on a 3" line and a fourth bathroom if the WC is 15' horizontally from the other fixtures. 4" is overkill from the old days of plumbing.
We haven't need to use 4" since the time of the dead plumbers and dinosaurs.
School districts around here even require 6" outside the building for minor bathroom groups just to prevent service calls for all the junk kids flush!
What various PDF tools?
 

PrecisionPlum

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Why is a 2" line needed for the WC? I thought it could be 1/2 of the dia. of the line being vented.

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