# possible venting issue for kitchen sink?



## scoooter (Oct 4, 2011)

I am re-doing the drain line to make it a dual drain for a sink. This is what I have.
	

		
			
		

		
	








    The vertical pipe on the right is the vent line, am I too far away to leave the drain line as is or do I need to put a better vent in? I have already drywalled so my only option would be to do something like this inline Shop Keeney Mfg. Co. Studor Mini-Vent Plumbing Vent at Lowes.com or this Shop Keeney Mfg. Co. Black Plumbing Vent at Lowes.com


    Any thoughts?

    Scott


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## semipro (Oct 4, 2011)

I'm no plumber but I've done my own plumbing.  Your setup looks okay to me.  Those vents like the one you provide a link to are not always accepted by code depending upon where you live.   You could always stub out and plug a connection that you could later add the in-wall vent to if it was needed.  You could mark on the wall an access port to cut out later if you needed to add the vent.

Edit: if you've already installed the drywall the stub out idea is worthless I guess.


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## Morgan (Oct 4, 2011)

Is this roughed in for a two compartment sink?  Typical way would have been to come out of the wall once, Tie both tail pieces into a tee, drop into a single trap and head to the wall.  If you hooking up a dishwasher put the dishwasher wye between the two tail pieces (This way both compartments and dishwasher are all protect by one trap).  If this is two separate sinks then you really should have a vent tied in between the two drains.  Also for distance I think your alright but keep in mind the distance of the trap arm (trap to vertical drain/vent in your case) should be less than 6' if your using 1 1/2" pipe or 8' if using 2"  One last thing, I can't see since there is a piece of 2x4 in the way, but where your stack goes from vertical to horizontal under the floor, there should be two 45s glued together for the transistion instead of using a 90 (common amateur mistake I see) and you must have an accessible clean out, if something plugs up you have no way to snake the drain, and if its a kitchen sink, chances are someday you will.


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## woodsman23 (Oct 4, 2011)

The links you provided will work just fine... go for it/


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## jdinspector (Oct 5, 2011)

This is not vented correctly. The drain openings are too far from the vertical vent. A "studor" vent (aka an AAV or air admittance valve) would help immensely. Check your local jurisdiction for code compliance. They are not allowed in my local area (northern IL), or anywhere in Illinois that I am aware of.

In any case, you have to get this vented correctly. If it is not vented, you'll have drain problems and could have sewer gas problems in the future. NOW is the time to get it done properly.

Just a question... how far along are you with drywall? Cutting out some drywall and patching is pretty simple (less than an hour or two) of work.


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## semipro (Oct 5, 2011)

jdinspector said:
			
		

> This is not vented correctly. The drain openings are too far from the vertical vent.



How far away can they be?  6 and 8 ft. were mentioned above for 1.5" and 2" pipe, respectively.  In the photo it looks like they're less than 6 ft. away from the vent.


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## scoooter (Oct 5, 2011)

Morgan said:
			
		

> Is this roughed in for a two compartment sink?  Typical way would have been to come out of the wall once, Tie both tail pieces into a tee, drop into a single trap and head to the wall.  If you hooking up a dishwasher put the dishwasher wye between the two tail pieces (This way both compartments and dishwasher are all protect by one trap).  If this is two separate sinks then you really should have a vent tied in between the two drains.  Also for distance I think your alright but keep in mind the distance of the trap arm (trap to vertical drain/vent in your case) should be less than 6' if your using 1 1/2" pipe or 8' if using 2"  One last thing, I can't see since there is a piece of 2x4 in the way, but where your stack goes from vertical to horizontal under the floor, there should be two 45s glued together for the transistion instead of using a 90 (common amateur mistake I see) and you must have an accessible clean out, if something plugs up you have no way to snake the drain, and if its a kitchen sink, chances are someday you will.




The right drain is almost exactly 4 feet from the vertical vent.  Can I cap the left one and just do a tee into one trap for both?

Where it goes from vertical to horizontal is a 90.  That's how the house was built in 74.  I have already put cabinets and 5k worth of granite (my wife's idea) on top of it, so I don't think now is the time to change it....  We have never had a problem with it before.

Scott


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## jdinspector (Oct 6, 2011)

I attached a diagram of vent distances. Yes, you could cap one of the drains. However, if you use a common trap, you'll hear water gurgling in the right sink when the left sink is draining (and vice versa). Now that I know at what stage you're at, I'd just go forward with what I said earlier. I'm guessing there is no permit for the job or the AHJ (Authority Having Jurisdiction, aka- municipal inspector) would have had you change it. Put in an AAV, hide it behind the sink bowl and you'll be fine if there is ever an inspection.


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## gpcollen1 (Oct 6, 2011)

great info right there for some us DIYers


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## Morgan (Oct 6, 2011)

Yes you could just cap one, I would cap the farthest one from the stack and use the closer one.  90 at the bottom of the stack you will probably get away with although by Canadian Code vertical to horizontal transitions must always be made with two 45s and you must provide a cleanout.  Since this is a kitchen sink with grease and fat and everything else you may need one some day, maybe not though I guess.  Also on a side note, careful with that granite, any oil can cause bad stains that are hard to impossible to remove.......make sure you follow any sealing instructions you may have and do so every 6-12 months.  I have seen a few and heard of many more horror stories regarding peoples granite counter-tops.  Also DO NOT use any plumbers putty near them, silicone only for sealing purposes under your faucets.


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