Kitchen island proper venting question

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Lrryjrry

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I have a contractor building a kichen island now and he supposed to build a vent loop. After breaking the concrete, he decided not to build the loop vent but to just build a vent 3 inches above the drain pipe (please see the pictures). Would this be ok? He said its up to code and he will install a air admittance valve in addition to this vent being install. I am so worried due to I spent $50k for this remodel. He also ensured me that it's ok due to the 2" drain is only 3 feet long from the 3" main drain which going steep downward.

image.jpg
 
Sounds like he will be installing an AAV. I've been told some states prohibit them, so where are you located?
 
I am in California, but can the AAV with this vent working out ok?
 
Seems fine to me, but I'm no expert. Hang on and you will get your answer when the experts chime in.
 
Seems fine to me, but I'm no expert. Hang on and you will get your answer when the experts chime in.

Thank you, it made me worried. There's no permit being pulled since I want the job done quick for my children school
 
Depending on your local code an AAV is fine. I'm a plumber in VA and we use them all the time because code allows us. Only issue is they are a mechanical fitting so down the road if it fails u just need to swap it out which is very easy to do. Code here is only 4in above trap, but I like to stick them up high in order to prevent them from flooding kitchen if ur sink ever clogs. As far as function I see nothing wrong with it. And since ur ABS pipe looks good you really should have a well functioning kitchen
 
Depending on your local code an AAV is fine. I'm a plumber in VA and we use them all the time because code allows us. Only issue is they are a mechanical fitting so down the road if it fails u just need to swap it out which is very easy to do. Code here is only 4in above trap, but I like to stick them up high in order to prevent them from flooding kitchen if ur sink ever clogs. As far as function I see nothing wrong with it. And since ur ABS pipe looks good you really should have a well functioning kitchen

I hope this would work well. I just wonder if the vent would have any help? Since it's only having 1/4" up going to the wall.
 
i really do not understand why he did not put the pipe in the wall. and drill out the studs for the vent.

i am looking at a floor that was unnecessarily busted.

it looks like a combination is being used in stead of a tee..that is not allowed

He's taking down the wall soon due to we are making an kitchen island. Which vent pipe and AAV combination not allowed?
 
you cant use a combo in that position, it has to be a tee.

the swoop on the combo cuts off the vent,,,by changing that ,,you could eliminate the aav under the sink


We are taking down the wall, so the pipe can't go along the wall. Is there any solution except a vent loop? Would you please see if you could do me a big favor to draw up and show me how could make it better suck as where to put the T?
 
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hope this helps


41777d1352682182-island-sink-loop-vent-correct-installation-islandvent20122.jpg


2015-12-21_1656.jpg

image (14).jpg
 
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you cant use a combo in that position, it has to be a tee.

the swoop on the combo cuts off the vent,,,by changing that ,,you could eliminate the aav under the sink




I didn't see that was a combo like that I was paying more attention to the AAV question he is right here that's a no no
 
I don't specifically know under your code, but under IPC, you could just run the 3" over to the kitchen sink in place of the 2" that is there currently, without any need for an air admittance valve. That is my preferred method of venting island sinks. AAV's do work, but they also do fail.
 
California UPC

AVV is a NO NO.
I don't understand why the plumber just doesn't dig more out and do it right.
Lazy??

below that original vertical drain coming out of the concrete is a horizontal drain somewhere it doesn't keep going straight down.
which way is the drain going under the slab and how deep does it go vertically.

kitchen island vent.jpg
 
FROM THE CALIFORNIA UPC

909.0 Special Venting for Island Fixtures.

Traps for island sinks and similar equipment shall be roughed in above the floor and shall be permitted to be vented by extending the vent as high as possible, but not less than the drainboard height and then returning it downward and connecting it to the horizontal sink drain immediately downstream from the vertical fixture drain. The return vent shall be connected to the horizontal drain through a wye-branch fitting and shall, in addition, be provided with a foot vent taken off the vertical fixture vent by means of a wye branch immediately below the floor and extending to the nearest partition and then through the roof to the open air, or shall be permitted to be connected to other vents at a point not less than six (6) inches (152 mm) above the floodlevel rim of the fixtures served. Drainage fittings shall be used on all parts of the vent below the floor level, and a slope of not less than one-fourth (¼) inch per foot (20.8 mm/m) back to the drain shall be maintained. The return bend used under the drain-board shall be a one (1) piece fitting or an assembly of a 45 degree (0.79 rad), a 90 degree (1.6 rad), and a 45 degree (0.79 rad) elbow in the order named. Pipe sizing shall be as elsewhere required in this code. The island sink drain, upstream of the returned vent, shall serve no other fixtures. An accessible cleanout shall be installed in the vertical portion of the foot vent.
 
phishfood, that is oldschool, and actually the best way in my opinion

it would look like this . NOTE...you HAVE to get the pipe into the back corner of the cabinet

I wonder how we could connect the 3" pipe to a 3" drain pipe? I think he might welling to do that.
 
I read in your original post that the drain to the kitchen is 2", but that the drain it attaches to is 3". If so, then you can attach to that.
 

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