Hi,

I have a quick question about venting my kitchen drains. I posted here recently about other plumbing issues that came up as part of my remodel. I am trying hard to wrap my head around the concept of venting, so forgive me if I make no sense.

Since the beginning of time, my double basin since drained into the main stack. I had intended on just following the original path (although after looking at the rats nest, I'm not sure if it is even correct), but now I am wondering if I need to add a vent. Like I said, the drain went to the main stack and nothing else. Is a vent required, and if so, would an AAV be OK.

I have pictures but I can't see where to attach them...

Thanks

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I am trying hard to wrap my head around the concept of venting,

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Wrap no more! Here's how it works. Let me explain about vents. When you pull a plug or flush a toilet the water going down the pipe sets up a suction. This has to be relieved by outside air. Hence a pipe through your roof. If the vent is blocked by a birds nest or a dead critter the water will pull suction through the nearest trap and you will hear a gurgle. It may be a fixture trap or the toilet may talk to you but you will hear it someplace. While it is possible for the suction to pull enough water out of a trap to have sewer gas escape but it's more likely a smell will come from decaying food, grease or hair. And now you know about vents.
If your kitchen sink arms into a vent stack you're already vented. Good luck, Tom

Hi Carly

All good above by Tom, but if your sink drains into the "main stack" as you said (suggesting fixtures above the sink) then you will need to add an AAV, for sure!

Do fixtures from above drain into this "main stack", or is this kitchen sink the only fixture on the stack? Let us know more, OK?

Mark

Yes.. the upstairs bathroom drains into the stack as well.

So I attached a before and after picture. The before is obviously a mess. So I framed a wall and am going to run the drain and water lines through the studs.

My question is where should I put the AAV. Does it have to be accessible or can it be between two of the studs?

Thanks

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Originally Posted by massplumber2008

Hi Carly

All good above by Tom, but if your sink drains into the "main stack" as you said (suggesting fixtures above the sink) then you will need to add an AAV, for sure!

Do fixtures from above drain into this "main stack", or is this kitchen sink the only fixture on the stack? Let us know more, OK?

Mark

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Thanks Speedball. That helps..

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Originally Posted by speedball1

Wrap no more! Here's how it works. Let me explain about vents. When you pull a plug or flush a toilet the water going down the pipe sets up a suction. This has to be relieved by outside air. Hence a pipe through your roof. If the vent is blocked by a birds nest or a dead critter the water will pull suction through the nearest trap and you will hear a gurgle. It may be a fixture trap or the toilet may talk to you but you will hear it someplace. While it is possible for the suction to pull enough water out of a trap to have sewer gas escape but it's more likely a smell will come from decaying food, grease or hair. And now you know about vents.
If your kitchen sink arms into a vent stack you're already vented. Good luck, Tom

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Does it have to be accessible or can it be between two of the studs?

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A AAV MUST be installed where it can be serviced or replaced. This can be installed in the cabinet just downstream from the trap, (seem image) Good luck, TomAnd Mark, You did notice I said vent stack didn't you? Cheers, Tom

I do now. Thanks.

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Originally Posted by speedball1

A AAV MUST be installed where it can be serviced or replaced. This can be installed in the cabinet just downstream from the trap, (seem image) Good luck, TomAnd Mark, You did notice I said vent stack didn't you? Cheers, Tom

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