# Combination drain & vent method



## swedishcharm21 (Oct 29, 2011)

Here in Michigan, Combination drain & venting is allowed......for now. I never have used this venting method and never will. There is no need for this venting method and due to the allowance (at least on MI) of AAV's, I think it should be removed from our Michigan plumbing code. Exception; Floor sinks, drains.

When I was an inspector, I only had seen 3 jobs where this was "attempted".

I failed all 3. 2 of them because their sizing was wrong, and the third because they had a laundry standpipe in the system.

So, does your state of municipality allow Comb drain & vent? if so, have you used it? if so why?

do you think it should be removed from your code?

Whats your take on this?


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## drtyhands (Aug 16, 2008)

How you gunna vent them floor sinks serving the coolers in the grocery store.

No vertical risers off the horizontal,everything on a 45.Oversize traps and trap arms.Beautiful working system.Works great and about as easy to install as it gets.

Edit:
gotta go through administrative before you put it in the ground


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## nhmaster3015 (Aug 5, 2008)

We do it all the for island sinks and floor drains. Screw AAV's


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## Mississippiplum (Sep 30, 2011)

nhmaster3015 said:


> We do it all the for island sinks and floor drains. Screw AAV's


Amen to that man. For island sinks we run 3 inch and then use a 3by 1 1/2 tee to tie the trap arm in. A cleanout goes on the top of the tee for rodding purposes.


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## swedishcharm21 (Oct 29, 2011)

Seems some of you guys do not like the AAV. Why not? Is it permitted in your state?


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## drtyhands (Aug 16, 2008)

i think we're talking about a couple dfrnt systems


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## swedishcharm21 (Oct 29, 2011)

DRTYHANDS-I agree with you about the floor sinks. As far as lavs, sinks and drinking fountains, I do not see why an AAV could not be used IF it is permitted.


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## drtyhands (Aug 16, 2008)

swedishcharm21 said:


> Seems some of you guys do not like the AAV. Why not? Is it permitted in your state?


rubber fails


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## TX MECH PLUMBER (May 27, 2011)

It's allowed here and I love it for floor drains, floor sinks, but that's it


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## drtyhands (Aug 16, 2008)

swedishcharm21 said:


> DRTYHANDS-I agree with you about the floor sinks. As far as lavs, sinks and drinking fountains, I do not see why an AAV could not be used IF it is permitted.


 When I was a kid I would blindly follow code like a booksmart inspector.Now I've learned over the past few years that the code has been written in not always the best interest of the community it serves.
Just my opinion...AAVs aren't a good way out.Sometimes necessary but not like some cheats are using them.


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## TX MECH PLUMBER (May 27, 2011)

Aav are hack work!!! And island sink maybe. But that's it!! Here you can use them all you want as long as you have one vent terminate outside!!! But I hate them I think they are just laziness !!!!


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## swedishcharm21 (Oct 29, 2011)

Drtyhands- Are you a Licensed plumber? Just curious.


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## swedishcharm21 (Oct 29, 2011)

I personally use AAV's on islands. Everything else, I have many venting options available.


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## drtyhands (Aug 16, 2008)

swedishcharm21 said:


> I personally use AAV's on islands. Everything else, I have many venting options available.


 I use a loop vent on islands wye and eighth on the foot vent with cleanout to keep the soap membrane from caking up.Keeps the kitchen from stinking up n flooding in case a guy cannot get aav above flood rim


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## Widdershins (Feb 5, 2011)

drtyhands said:


> I use a loop vent on islands wye and eighth on the foot vent with cleanout to keep the soap membrane from caking up.Keeps the kitchen from stinking up n flooding in case a guy cannot get aav above flood rim


 An AAV doesn't need to be above the flood rim, the only height restriction is that it must be 6" above the trap.

As for stinking up or flooding, that isn't really a problem unless the rubber seal fails -- Negative pressure is the only condition that will cause the valve to open.

As for failure of the rubber seal, it is far less likely to fail than a submerged flapper valve or ballcock seal.


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## swedishcharm21 (Oct 29, 2011)

drtyhands- I am going to go on the limb and say your knowledge of plumbing is LIMITED at best.

By the way...I am not a text book smart inspector or whatever you say...I am one of the best plumbers in the field.

26 years as a Master plumber, in the field.

7 years as an inspector

after inspecting I resumed to working in the field to this day.

I am a sole owner and employ 15 licensed plumbers and 30 apprentices.

Former UA instructor

Former Plumbing board member


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## plbgbiz (Aug 27, 2010)

Widdershins said:


> ...As for failure of the rubber seal, it is far less likely to fail than a submerged flapper valve or ballcock seal.


Apples and oranges Mr. Shins. Do the kitchen cabinets in your neck of the woods come with an an overflow tube that passes water directly to the drain?


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## swedishcharm21 (Oct 29, 2011)

drtyhands said:


> When I was a kid I would blindly follow code like a booksmart inspector.Now I've learned over the past few years that the code has been written in not always the best interest of the community it serves.
> Just my opinion...AAVs aren't a good way out.Sometimes necessary but not like some cheats are using them.



The code is ALWAYS to be followed! It is there for a reason! The code is all about the minimum. There is NEVER one reason you should need to perform a plumbing procedure that causes you to plumb it out of code. From your postings and replies, I will stick to what I said about you- Your knowledge is LIMITED at best.


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## ChrisConnor (Dec 31, 2009)

swedishcharm21 said:


> The code is ALWAYS to be followed! It is there for a reason! The code is all about the minimum. There is NEVER one reason you should need to perform a plumbing procedure that causes you to plumb it out of code. From your postings and replies, I will stick to what I said about you- Your knowledge is LIMITED at best.


I don't think he said anything about not following code, but was implying that he goes over the code minimums in his installations..


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## plbgbiz (Aug 27, 2010)

Being approved by the code is hardly the end all of whether or not a particular product or material is a good choice to put in a plumbing system. Unless of course you're a service plumber. :laughing:

Bituminous fiber pipe is still approved by the code. I sure wish somebody was still installing it. Thin wall PVC was an awesome addition to the code. And don't ya just love foam core PVC? Let's not forget the great admittance to the code of push-fit angle stops and Sharkbites. :laughing:

I've replaced more than a few faulty Studors.

Like Gramps used to say,_ "All good plumbing is in the code but not all code is good plumbing"_.


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## swedishcharm21 (Oct 29, 2011)

I hear you. But there is also other approved materials that any experienced plumber will know not to use. I agree, I hate sharkbite...etc, and we can always use copper or solid core PVC or Wrot fittings. I dont think you understand what I was talking about plbgbiz

By the way, I am sure your code in OK is different than Michigan.Also, we do not allow Bituminous. We are also pushing to get sch30 removed.


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## plbgbiz (Aug 27, 2010)

swedishcharm21 said:


> ...So, does your state of municipality allow Comb drain & vent? if so, have you used it? if so why?
> 
> do you think it should be removed from your code?
> 
> Whats your take on this?


It's allowed here under the IPC 2009 - Section 912

If possible I think almost anything is better than adding a mechanical device to the drainage and vent system. Not that I haven't done it, it's just not my preference. A properly sized and installed combination drain and vent will have no mechanical parts to fail, is washed by a fixture, and is concealed in the wall.


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## plbgbiz (Aug 27, 2010)

swedishcharm21 said:


> ...I dont think you understand what I was talking about plbgbiz....





swedishcharm21 said:


> I personally use AAV's on islands....


I think I understood just fine. I just disagree. I believe this photo to depict far superior venting for an island than an AAV.

Again, no disrespect intended, just my opinion.

No different than a code approved sewage ejector. Sometimes it is the only option but I prefer non-mechanical gravity systems. One less man-made device to fail.


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## ChrisConnor (Dec 31, 2009)

Mechanical vents fail. period.

But I don't have a problem with them on new construction, there are thousands of quick build condominiums going up with those things. People who will be my future customer when they fail. Everything I work on is because of the cheapening of the construction. That's why I am in service.


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## GREENPLUM (Jul 27, 2008)

So what do you do when an AAV fails, sell the customer a VTR


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## Titan Plumbing (Oct 8, 2009)

Are larger pipe sizes always better?


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## plbgbiz (Aug 27, 2010)

Titan Plumbing said:


> Are larger pipe sizes always better?


I don't think so. But that's just me. I think k/s drains are less likely to have build up in a 2" line than they are in a 3". That's why I prefer the method in the pic over a 3" santee as well.

Over sized 4" and 6" sewers are a contributing factor to the problems of line carry on low flow toilets as well.


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## Titan Plumbing (Oct 8, 2009)

plbgbiz said:


> I don't think so. But that's just me. I think k/s drains are less likely to have build up in a 2" line than they are in a 3". That's why I prefer the method in the pic over a 3" santee as well.
> 
> Over sized 4" and 6" sewers are a contributing factor to the problems of line carry on low flow toilets as well.


I agree completely. I like combo systems for their self-scouring effects. We have thousands of combo systems around here and have very few issues that are any different from stack systems. I think folks who poo poo the combo systems are just stuck in their old ways.


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## Widdershins (Feb 5, 2011)

plbgbiz said:


> Apples and oranges Mr. Shins. Do the kitchen cabinets in your neck of the woods come with an an overflow tube that passes water directly to the drain?


 I've never had one fail. 

Knock on wood.:yes:


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## nhmaster3015 (Aug 5, 2008)

Couple years back I had a journeyman put an aav on a shower installation. He's working for some hack now. :thumbsup:

The purpose of a vent is to compensate for positive and negative pressures within the system. How in hell does an AAV do anything for positive pressures? 

37 years plumbed have I and not once failed I have to properly vent a fixture. More work it is but I GET PAID FOR MORE WORK! I don't EVER give the customer a choice. Either vent it right or call some hack to screw a f'ing AAV on top and forget about it. And you wonder why more and more homeowners are doing their own work. 

Now I'm filled with anger and rage.......time for the Crown :thumbsup:


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## Mississippiplum (Sep 30, 2011)

I hate aav's and we/I never use the pieces of ****. Running the waste into a 5 gallon bucket underneath the sink is better then a aav, when a aav fails the trap will siphon and probly the near by traps also if the near by fixtures are vented off the same aav.


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## rocksteady (Oct 8, 2008)

Mississippiplum said:


> I hate aav's and we/I never use the pieces of ****. Running the waste into a 5 gallon bucket underneath the sink is better then a aav, when a aav fails the trap will siphon and probly the near by traps also if the near by fixtures are vented off the same aav.


When AAV's fail, in my experience, they fail in the open position. That means the trap functions fine but the house stinks like sewer gasses. They also leak when installed under a counter-top when the sink backs up and the H.O. pounds on the drain with a plunger for 30 minutes. Neither are too big of a deal for me as a service plumber because they get, guess what? Another AAV! :thumbup: If there's a practical way to atmospherically vent the fixture I'll of course recommend and bid that but often times they're stuck with the AAV. I really don't see why one would be needed in new construction though.







Paul


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## plbgbiz (Aug 27, 2010)

nhmaster3015 said:


> .....time for the Crown :thumbsup:


Try the black label.


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## Nikolai (Dec 17, 2009)

swedishcharm21 said:


> drtyhands- I am going to go on the limb and say your knowledge of plumbing is LIMITED at best.
> 
> By the way...I am not a text book smart inspector or whatever you say...I am one of the best plumbers in the field.
> 
> ...


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## ChrisConnor (Dec 31, 2009)

Mississippiplum said:


> I hate aav's and we/I never use the pieces of ****. Running the waste into a 5 gallon bucket underneath the sink is better then a aav, when a aav fails the trap will siphon and probly the near by traps also if the near by fixtures are vented off the same aav.



I've never seen one fail closed. And if were possible to fail stuck in the closed position and siphoned the trap, it would be the same result if it failing open, sewer gasses in the home.


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## nhmaster3015 (Aug 5, 2008)

plbgbiz said:


> Try the black label.


Reserve select for me thank you :thumbsup:


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## drtyhands (Aug 16, 2008)

swedishcharm21 said:


> drtyhands- I am going to go on the limb and say your knowledge of plumbing is LIMITED at best.
> 
> By the way...I am not a text book smart inspector or whatever you say...I am one of the best plumbers in the field.
> 
> ...


 Swedish
A forum member just wrote me and asked if there was something I said to piss you off.I had to look this post up.Just saw it.
The textbook statement was not directect towards you.
I have a hard time listening to textbook inspectors who do not know the intricacies of building a project and the give and take necessary to build something that a arc/eng can't yet they put it on paper.
I write funny,a little rushed sometimes,trying to fit ten pounds of in a five pound you know the rest.
I thought briefly about the textbook thing when I wrote it.Maybe if I would have proofed before post I would've seen something.

As far as my skill level and knowledge....I'm not even going to go there.
I Just offer this,if you find it hard to find out the truth here on the internet there are a few avenues I can direct you in to help.Probably won't be necessary I'm guessing.


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## drtyhands (Aug 16, 2008)

swedishcharm21 said:


> The code is ALWAYS to be followed! It is there for a reason! The code is all about the minimum. There is NEVER one reason you should need to perform a plumbing procedure that causes you to plumb it out of code. From your postings and replies, I will stick to what I said about you- Your knowledge is LIMITED at best.


Now I just saw this one..
I guess you and I have a little relationship going here.


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## stillaround (Mar 11, 2009)

:laughing:A little ancillary drama spices up the thread. I mean at least no one called the inspector an oxymoron or anything ( swedish charm...does that even go together ):laughing::laughing::laughing: Just kidding......just kidding...just kidding.....there are some lovely swedish ladies out there, and certainly one can only infer that the inspector is swedish:laughing::laughing::laughing:....and I presume a very fine inspector indeed...Ya sure


I dont want to get in trouble


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## nhmaster3015 (Aug 5, 2008)

stillaround said:


> :laughing:A little ancillary drama spices up the thread. I mean at least no one called the inspector an oxymoron or anything ( swedish charm...does that even go together ):laughing::laughing::laughing: Just kidding......just kidding...just kidding.....there are some lovely swedish ladies out there, and certainly one can only infer that the inspector is swedish:laughing::laughing::laughing:....and I presume a very fine inspector indeed...Ya sure
> 
> 
> I dont want to get in trouble


Quit doing my job! :laughing:

Ingy dingy dingy :laughing:

Dirty Hands, around here questioning a mans knowledge is reason to duel. Plungers at 10 paces


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## drtyhands (Aug 16, 2008)

swedishcharm21 said:


> Drtyhands- Are you a Licensed plumber? Just curious.


Gawd I suck at being a forum member sometimes.
I went back to the start of this thread to "Get the vibe"
Sorry fellow forum members.

Swedish,
My lack of responses to you was because you and I were hitting and missing while I would pop in and jump around "Todays Posts".I lost track on this thread.You had something that was important to you talk about and you were attempting a consistant dialogue with me.
Poor Guy,I feel a little bad now.It's kindof cute in a way how things can twist out.

License...
27 years old,1989.You remember the recession.A contractor out of Mo. told me to get my license so when a project inside of Dodger stadium came up I could bid on it.Wonder how he came to trust a 27 year old California boy.

Where the F*** did you get the Idea I was an idiot.In my first post of this thread I gave you some of the most important elements of combination waste and vent separating it from a standard waste and vent.


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## ToUtahNow (Jul 19, 2008)

drtyhands said:


> When I was a kid I would blindly follow code like a booksmart inspector.Now I've learned over the past few years that the code has been written in not always the best interest of the community it serves.
> Just my opinion...AAVs aren't a good way out.Sometimes necessary but not like some cheats are using them.


Remember the Codes are the MINIMUM standards.

Mark


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## drtyhands (Aug 16, 2008)

ToUtahNow said:


> Remember the Codes are the MINIMUM standards.
> 
> Mark


I know and I have written in previous posts to this subject.
Piss me off to no end that I didn't finish the thought in that exact post.


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## mccmech (Jul 6, 2011)

plbgbiz said:


> Try the black label.



To heck with the label, just pass the bottle. Hic-up


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## ToUtahNow (Jul 19, 2008)

swedishcharm21 said:


> drtyhands- I am going to go on the limb and say your knowledge of plumbing is LIMITED at best.
> 
> By the way...I am not a text book smart inspector or whatever you say...I am one of the best plumbers in the field.
> 
> ...


I would put "drtyhands" up against anyone on here without a second thought. I was working on a high rise project a few years ago and it turned out "drtyhands" was doing the TI in one of the Penthouses. He had all sorts of inside information which really helped me in my investigation. Here is the finished unit he was on

Mark


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## Mississippiplum (Sep 30, 2011)

ToUtahNow said:


> I would put "drtyhands" up against anyone on here without a second thought. I was working on a high rise project a few years ago and it turned out "drtyhands" was doing the TI in one of the Penthouses. He had all sorts of inside information which really helped me in my investigation. Here is the finished unit he was on
> 
> Mark


That's one hell of a penthouse.


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## drtyhands (Aug 16, 2008)

ToUtahNow said:


> I would put "drtyhands" up against anyone on here without a second thought. I was working on a high rise project a few years ago and it turned out "drtyhands" was doing the TI in one of the Penthouses. He had all sorts of inside information which really helped me in my investigation. Here is the finished unit he was on
> 
> Mark


I wish you would let me throw down my own dang chips.I don't hava whole Hellava lot of em comin' in these day and I was saving that for a bigun.
I had this one tagged and bagged Mark.





Teasing partner


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## Titan Plumbing (Oct 8, 2009)

I'm enjoying the popcorn..thanks DH and Mark.


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## drtyhands (Aug 16, 2008)

Anybody whatching "Hell on Wheels" .
The Swede is a pretty impressional character.


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## ToUtahNow (Jul 19, 2008)

drtyhands said:


> I wish you would let me throw down my own dang chips.I don't hava whole Hellava lot of em comin' in these day and I was saving that for a bigun.
> I had this one tagged and bagged Mark.
> 
> 
> ...


You know how I am. Don't mess with my family, my friends or my guns because my hackles will go up.

Mark


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## drtyhands (Aug 16, 2008)

ToUtahNow said:


> You know how I am. Don't mess with my family, my friends or my guns because my hackles will go up.
> 
> Mark


I hate it when you make me cry.
My dog is laughing at me again.


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## drtyhands (Aug 16, 2008)

Are Hackles our future...The multiple offspring of the hack.


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## ToUtahNow (Jul 19, 2008)

drtyhands said:


> I hate it when you make me cry.
> My dog is laughing at me again.


Great now I have an edit:

You know how I am. Don't mess with my family, my friends, my dogs or my guns because my hackles will go up.

Mark


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## stillaround (Mar 11, 2009)

Judging from the pictures he's a brilliant architect and progressive interior designer...but I see very little of his plumbing design skills....therefore its theoretically possible he has limited knowledge....(I realize I dont have any business in this conversation)


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## Redwood (Sep 8, 2008)

ToUtahNow said:


> I would put "drtyhands" up against anyone on here without a second thought. I was working on a high rise project a few years ago and it turned out "drtyhands" was doing the TI in one of the Penthouses. He had all sorts of inside information which really helped me in my investigation. Here is the finished unit he was on
> 
> Mark





drtyhands said:


> I wish you would let me throw down my own dang chips.I don't hava whole Hellava lot of em comin' in these day and I was saving that for a bigun.
> I had this one tagged and bagged Mark.
> 
> Teasing partner


He shoulda known better than to mess with them Beverly Hills Plumbers.... 
:laughing::laughing::laughing::laughing::laughing:


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## plbgbiz (Aug 27, 2010)

ToUtahNow said:


> I would put "drtyhands" up against anyone on here without a second thought. I was working on a high rise project a few years ago and it turned out "drtyhands" was doing the TI in one of the Penthouses. He had all sorts of inside information which really helped me in my investigation. Here is the finished unit he was on
> 
> Mark


Why is Titan Plumbing's avatar on the wall? Just how many Zoners were on that job? :laughing:


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## plumber666 (Sep 19, 2010)

Good thread, was going to ask the oxymoron question on one of the OPs earlier threads.


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## Redwood (Sep 8, 2008)

plumber666 said:


> Good thread, was going to ask the oxymoron question on one of the OPs earlier threads.


Are you saying someone is a moron because their brain is oxygen deprived? :laughing:


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## hroark2112 (Apr 16, 2011)

OK...educate the idiot time please.

What's a combination drain & vent method??


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## plbgbiz (Aug 27, 2010)

IPC 2009 - Definitions - Page 10:

*COMBINATION WASTE AND VENT SYSTEM.* A specially designed system of waste piping embodying the horizontal wet venting of one or more sinks or floor drains by means of a common waste and vent pipe adequately sized to provide free movement of air above the flow line of the drain.


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## Redwood (Sep 8, 2008)

This is all so new to me.... :laughing::laughing::laughing:
http://www.plumbingzone.com/f6/2009-ipc-combination-waste-vent-14928/

I mean a new forum...
A new member that has forgotten more than we know...
And not understanding how to use the forum search feature....

I just don't get it why they don't get it......


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## swedishcharm21 (Oct 29, 2011)

no hard feelings. I can understand how text can be misleading at times. We are all professionals in the field. I respect that much, and my fellows.


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## drtyhands (Aug 16, 2008)

swedishcharm21 said:


> no hard feelings. I can understand how text can be misleading at times. We are all professionals in the field. I respect that much, and my fellows.


 And there is the Charm.Great night to ya Svede


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## brass plumbing (Jul 30, 2008)

when the rubber fails it is meant to be serviceable


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## Plumbus (Aug 4, 2008)

brass plumbing said:


> when the rubber fails it is meant to be serviceable


That's the point. With a vent there is no need for maintenance. 
More expensive? Yes. More reliable? Yes. And, a vent compensates for both positive and negative pressure.


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