Studer vent

[Bryant16e]

Good afternoon guys, I ran in to a studer vent in an attic this morning. Its a sewer vent that does not terminate through the roof but in the attic. Have any one of you ran in to this before, any problems?

[Brad Manor]

I'm not familiar with the term "studer vent".... Is it a vent, or an air admittance valve type of thing?

-Brad

[Chad Fabry]

"Studor" makes vents.

They make mechanical vents that are black and aren't generally allowed except in manufactured homes and air admittance vents/ valves that are generally allowed and are white.

[Richard Moore]

Couple of IRC code issues with AAV's...

AAV's in attics need to be installed a minimum of 6" above the insulation.

Probably most important: P3114.7 Vent required. Within each plumbing system, a minimum of one stack vent or a vent stack shall extend outdoors to the open air. (my underline)

In other words, the attic AAV can't be a substitute for the normal "free-to-air" main vent above the roofline. If it's just for an individual or branch vent, should be no problem...assuming, as Chad pointed out, it is a permitted AAV.

[Richard Moore]

So...you can vent into a Studer?

[Bryant16e]

I have never heard the term either I googled it and there is quite a bit of info on it. I attached a few photos please take a look, see if it changes anyones mind. If it is ok you may want to research it for your areas. Thanks

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[Bryant16e]

Come on guys I know someone has something..........

[Brandon Whitmore]

I can tell you they aren't allowed in Oregon..... all I got.

[Richard Moore]

Originally posted by Bryant16e

Come on guys I know someone has something..........

Not sure what you want Eric. Ugly glue job?

That is in fact an AAV. They appear to be approved in Florida (according to Studor's own web-site http://www.studor.com/approvals.htm ). It's not big enough to be the main stack. So, therefore, and judging purely by your photos, I suspect it is just fine. But...could just as well be wrong depending on other factors.

[Bryant16e]

I gotcha thanks so much for the feed back.

[tedmen]

Other than the fact it appears to be added after the fact of the homes original build and they did not want to remove a couple of shingles and cut a hole to save many I don't know why they would have used it. I say added after the fact for an add on because I do not see a plumbing inspector allowing it on a new build. Of course it could have been an oops and never ran it thru the roof before it got shingled and an inspector found a pipe just venting into the attic.

[msteger]

I see these type of vents routinely under kitchen island or pensinulas with sinks. No way to easily connect the drain to the stack vent if a wall is not nearby, so the air admittance valve is used. I was under the impression that a Studor vent and air admittance valve are the same thing (one a general name and one a brand name) and are only allowed for one fixture. In other words, the whole house can't be full of these in lieu of stack vents.

Question for you all - Having a studor valve installed under the kitchen sink does not remove the need for a high loop or air gap in the drain line for a dishwasher draining into garbage disposals, correct??

[randynavarro]

Originally posted by msteger

Question for you all - Having a studor valve installed under the kitchen sink does not remove the need for a high loop

Yes. A high loop is not needed.

or air gap in the drain line for a dishwasher draining into garbage disposals, correct??

Air-admittance valves do not eliminate the need for an air gap (if one is required in your area.)

[Brian G]

Plumbing isn't my strongest subject, so I have a couple of questions.

A. What does an AAV have to do with the need for a high loop on a dishwasher? I've always been told the high loop is there to physically deter backflow into the dishwasher if the drain backs up or clogs, and the water level rises toward the sink.

B. Why is it necessary to have at least one vent pipe going to the outdoors, if AAV's really work? I've heard a couple of different takes on this locally, so I'm interested to see what various TIJ family members have to say about it.

Brian G.

Exercising the Weaker Muscles Makes Them Stronger [:-graduat

[Richard Moore]

There may be some confusion here. I think Randy's first answer is talking about the AAV replacing an island loop vent for the sink drain rather than the high loop for the dishwasher drain line.

The full question was "Question for you all - Having a studor valve installed under the kitchen sink does not remove the need for a high loop or air gap in the drain line for a dishwasher draining into garbage disposals, correct??". And the answer to that would be...No, it does not.

As for B: AAVs admit air but, by design, do not allow gasses to escape. If there was an overpressure situation in the sewer line, that excess pressure could not be relieved if all vents were AAVs. In an extreme case, gasses might bubble past the traps. With at least one venting freely to the outdoors, any excess pressure in the house DWV system would be relieved. I honestly don't know if that's the "official" reason, but it makes sense in my head.

[Brandon Chew]

As for B: AAVs admit air but, by design, do not allow gasses to escape. If their was an overpressure situation in the sewer line, that excess pressure could not be relieved if all vents were AAVs. In an extreme case, gasses might bubble past the traps. With at least one venting freely to the outdoors, any excess pressure in the house DWV system would be relieved. I honestly don't know if that's the "official" reason, but it makes sense in my head.

That's correct. The AAV is a check-valve, only allowing air to flow into the system. The house system needs to have at least one vent that will allow air to flow in both directions.

[msteger]

Thanks guys.

[choche]

An Studer vent is an AAV it's just calling it by the brand name.You need at least one fresh air vent that terminates through roof to outside air and at least one half the diameter of the underground. The baffle opens due to any pressure change in the sytem, and they have been known cause fixtures to gurgle if theirs other vent problems in sytem. I would never put one on a laundry even though it's legall because of suds back-up, and vent problems down the line especilly on the newer high efficency ones. They work great under kitchen sink at least 4 inches above the drain line,and I'm pretty sure they can go vertical and on a 45. Hope this helps???

[Dio]

I just moved in to a new house which has a septic system. In less than two months, the drain field had to be replaced. I noticed that there is sewage smell under the sink that is closest to the septic tank. I noticed that there is a vent device under the sink but it does not appear that there is a vent pipe going out to the roof. 

Do anyone of you know if in Florida is it required to have a drain vent or can they just install those single vents under the sink?

 

Edited February 13, 2020 by Dio