Sink drain vent

[Meanmetz]

have 2" sink drains on first and second floors can I tie first floor vent into second floor vent @ 42". if so does upstairs vent need to be increased

 

[WorthFlorida]

Most venting only 1.5" pipe is needed but up to three inches through the roof. 10 fixture units per 1.5" vent pipe. Depending on the age of the home, most newer homes they usually will be 2".

How many fixtures can share a vent?
Under the Uniform Plumbing Code, a 2" vent can handle 24 fixture units(F.U). In a residence, a lavatory sink= 1.0 F.U., bathtub/shower= 2.0 F.U. and a toilet 1.6 gallon or less= 3.0 F.U, greater than 1.6 gallon= 4.0 F.U.

 

[Sponsor]

 

[Meanmetz]

Most venting only 1.5" pipe is needed but up to three inches through the roof. 10 fixture units per 1.5" vent pipe. Depending on the age of the home, most newer homes they usually will be 2".

How many fixtures can share a vent?
Under the Uniform Plumbing Code, a 2" vent can handle 24 fixture units(F.U). In a residence, a lavatory sink= 1.0 F.U., bathtub/shower= 2.0 F.U. and a toilet 1.6 gallon or less= 3.0 F.U, greater than 1.6 gallon= 4.0 F.U.

 

[Jeff H Young]

have 2" sink drains on first and second floors can I tie first floor vent into second floor vent @ 42". if so does upstairs vent need to be increased

tie them together min 6 inches above 2nd floor sink top. no increase