Common Vent -- add a sink to floor drain dry vent ?

[notaplumberforsure]

hi,

first post here but thanks to all posters and esp. Terry !!

anyway,

i currently have a floor drain w a dry vent that goes up thru floor, thru ceiling, crosses over and joins another vent and then out roof. this is 70s house
with what appears to be convential venting ( a vent for each drain ) throughout.

it is 2" metal pipe.

my question is:

i would like to "tap" into the dry vent approx. 18" up from the floor ( same floor i guess ?) ( as needed for sink) and drain a bar/kitchen sink thru there, and am a bit confused by the code. it appears as if code forbids a vertical wet vent since it's not a lavatory sink. but, could this be considered a common vent if i add the sink only to the dry vent at approx 18" up ( less than 8 ft) ? and, am i right in observing that common vents are a subclass/special case of vertical wet vents since the vent from the lower fixture on the given floor for the vent would be wet at times ? ( of course will double check pipe sizing reqts but initially seems good)

just noticed that code states "at different levels .. ... the vent shall connect as a vertical extension of the vertical drain ..." - and i there is no vertical drain in this scenario presently -- i suppose that if i use the vent as a vertical drain for that short run that would create one but not sure if that's intended case

and thinking maybe not good idea since if any downstream resistance to flow water would flood out of floor drain easily.

but, maybe ?

or, out of the question ?

any help/comments appreciated .

thanks

 

[John Gayewski]

Illinois has its own code.

Your sure this is a true dry vent and is vertical with no horizontal portions underground?

 

[Sponsor]

 

[John Gayewski]

I think 890.1500 (c) allows you to do what you want to do.

You have a 2" pipe and the trap for the upper fixture should be 1.5". So I think your good.

 

[sajesak]

hi,

first post here but thanks to all posters and esp. Terry !!

anyway,

i currently have a floor drain w a dry vent that goes up thru floor, thru ceiling, crosses over and joins another vent and then out roof. this is 70s house
with what appears to be convential venting ( a vent for each drain ) throughout.

it is 2" metal pipe.

my question is:

i would like to "tap" into the dry vent approx. 18" up from the floor ( same floor i guess ?) ( as needed for sink) and drain a bar/kitchen sink thru there, and am a bit confused by the code. it appears as if code forbids a vertical wet vent since it's not a lavatory sink. but, could this be considered a common vent if i add the sink only to the dry vent at approx 18" up ( less than 8 ft) ? and, am i right in observing that common vents are a subclass/special case of vertical wet vents since the vent from the lower fixture on the given floor for the vent would be wet at times ? ( of course will double check pipe sizing reqts but initially seems good)

just noticed that code states "at different levels .. ... the vent shall connect as a vertical extension of the vertical drain ..." - and i there is no vertical drain in this scenario presently 신용카드 현금화-- i suppose that if i use the vent as a vertical drain for that short run that would create one but not sure if that's intended case

and thinking maybe not good idea since if any downstream resistance to flow water would flood out of floor drain easily.

but, maybe ?

or, out of the question ?

any help/comments appreciated .

thanks

Started looking for a place to connect my basement powder room ejector pit vent. The guys who did the rough-in 16 years ago did not provide a vent. Maybe they were assuming I could tie into the overhead waste line but that is a different subject.

My kitchen sink trap drains into a 2” vertical line which connects to a sanitary tee below the floor and runs horizontally. Here is what surprised me. The vent also connects to the sanitary tee and runs horizontally the opposite direction about 4’ before it turns up and runs vertically through the roof. I don’t know squat about venting but common sense suggest the vent should connect to the vertical section of the drain line. I guess the sanitary tee directs the flow away from the vent and if it is sloped properly it should be ok. I know it works because we have lived here for a year and never had a problem. The kitchen sink drains great.

 

[notaplumberforsure]

Illinois has its own code.

Your sure this is a true dry vent and is vertical with no horizontal portions underground?

it comes out of the concrete slab thru the floor plate/sill and is approx 2 ft from the floor drain with no other fixtures closer than 15 ft -- so, good question and i am assuming dry and no branches --- do you think if i/plumber uses a transponder i could determine w better certainty ? would prefer to not disturb slab

the section downstream from floor drain was clogged at one point and the plumber used that drain to insert snake and cleaned clog thru it -- snaked all the way to beyond main stack exit

thanks for question

 

[notaplumberforsure]

I think 890.1500 (c) allows you to do what you want to do.

You have a 2" pipe and the trap for the upper fixture should be 1.5". So I think your good.

thanks for reply !! i looked at that and like you said looks good ! -- AND it answers my question regarding the IPC Common Vent actually being a special case of a vertical wet vent at least for practical considerations

 

[notaplumberforsure]

Started looking for a place to connect my basement powder room ejector pit vent. The guys who did the rough-in 16 years ago did not provide a vent. Maybe they were assuming I could tie into the overhead waste line but that is a different subject.

My kitchen sink trap drains into a 2” vertical line which connects to a sanitary tee below the floor and runs horizontally. Here is what surprised me. The vent also connects to the sanitary tee and runs horizontally the opposite direction about 4’ before it turns up and runs vertically through the roof. I don’t know squat about venting but common sense suggest the vent should connect to the vertical section of the drain line. I guess the sanitary tee directs the flow away from the vent and if it is sloped properly it should be ok. I know it works because we have lived here for a year and never had a problem. The kitchen sink drains great.

thanks for reply !!

similar situation here but the vent runs vertically from the point it exits the slab to the next floor ( 8 ft -- ish ) and then jogs over horizontally approx 3 ft before rising vertically thru ceiling of next floor into attic -- so i think i am good as far as practically concerns of draining -- ( glad yours drains well !) -- but did not want to invest alot in bar/kitchenette if plumbing not code -- thx