Help adding bathroom

[phishfood]

Modern toilets with low gallons per flush are actually much worse than older toilets that used several gallons per flush. These low consumption toilets dump that smaller amount of water MUCH faster than older toilets that took much longer to complete a flush, and in a gallons per second perspective, put more volume down the pipe than the older toilets.

The people writing the codes are not stupid.

 

[frodo]

Mr david's Post. spelled out that a wet vent fixtures shall be within the same story; provided, further, that fixtures with a continuous vent discharging into a wet vent shall be within the same story as the wet-vented fixtures. No wet vent shall exceed six {6} feet (1,829 mm) in developed length


let me explain the term same story, I will type slow so you can understand

the 1st floor and 2nd floor are different story's
AND
the 1st floor and 2nd floor are more than 6' above each other


a residential water closet is with 1.6 gpf per tank is 3FU

so to answer your answered question

NO you can not drain ANY fixtures into the vent from the first floor. You are calling a common vent a wet vent,
and are not understanding what a wet vent is


this is what you have to do in order to add a drain upstairs.

connect a sewage pipe to the existing sewer line BEFORE the vent .

this will entail busting the concrete and tieing into the sewer

 

[frodo]

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