Capping off un-used vent

[BillN]

We have a sink we disconnected and want to remove the vent stack. Its the only item connected to the line, that is drain goes down to basement and vent up to attic directly.

I do not want to remove the roof pipe to avoid having a hole in the roof. Is it best to cap it off in the attic or to join the pipe up to another plumbing vent? (worred that
water would collect in the capped vent).

Obviously easiest to cap to avoid routing pipes around the attic, but if its best to join it to another vent (thus the vent will inverted "Y" to another vent), is there anything special (angles, joins, etc) to worry about?

 

[Cookie]

What size is the vent and what material is it?

 

[Sponsor]

 

[Cookie]

Personally, I think you are wasting you money, time and effort by tying it in to another vent. If it is galvanized pipe it will rust just as much from the dampness in the vent and maybe more so, because their will be one less portion of the vent exposed to the atmosphere allowing the moisture to stay trapped in the vent longer.

 

[BillN]

What size is the vent and what material is it?

2" ABS into the attic. Have not crawled the attic yet to see if it changes up there.

 

[BillN]

Personally, I think you are wasting you money, time and effort by tying it in to another vent. If it is galvanized pipe it will rust just as much from the dampness in the vent and maybe more so, because their will be one less portion of the vent exposed to the atmosphere allowing the moisture to stay trapped in the vent longer.

If I cap it and it rains, the water would go into the pipe
then cap instead of flowing down to the drain. So main
concern is water build up and stagnation, etc. I guess I could cap it at the roof (outside) as well? Since its ABS into the attic I need to check what it is going to the roof.

Thanks for your replies!

 

[Cass]

Just leave it like it is...there is no need to cap it off...

 

[BillN]

Just leave it like it is...there is no need to cap it off...

Sorry to not be clear (new poster). The sink was to a wet bar in the living room. We are open the wall to the LR so we want to remove the (now unused) drain pipe. So down to the basement / waste line connect is easy. But the pipe to the roof is the one I want to cap or remove.

Thanks!