noisy aav problem and gurgling when draining bath

[craig james]

Hello out there: We have refurbished a bathroom, and the plumber hasshortened the outflow stack (which previously reached into the attic) so thatits top is now within the bathroom itself and has been boxed in and tiled,creating a small square shelf above the top of the stack (his idea, to give a"nicer" look to the bathroom). It has an Air Admittance Valve, and wenow hear a metallic tapping noise coming from behind the tiling when water hasbeen drained, and we assume this is the AAV valve opening and closing. Sometimesit’s an occasional tap, other times, one a second, other times more rapid. Theplumber has changed the AAV but it has not rectified the problem. If it is theAAV, should it be making this noise, and if so should it be so loud as to beheard through tiling and a boxed-in surround? Strangely, in a bid to solve the problem, the plumber fixed a restraint to the pipe stack itself within the box (not sure why). Since then it has reduced the amount of tapping noise when draining water in the bathroom but the tapping continues badly when draining units in the kitchen one floor below.

In case it's relevant, the AAV is above the outflow of the highest unit, the basin, by about 20cm.

Photo attached of the boxed in stack.

Also, the bath was relocated in the bathroom and obviouslynew pipework was put in. Now there is a gurgling noise from bath water as it finishesdraining. Is this to do with the AAV?

Thanks.

 

[mike-c]

http://www.nhbc.co.uk/Builders/Tech...echnicalGuidance/81/filedownload,37140,en.pdf

Your picture does not show any ventilation to the pipe box.
As for the ticking noise I would suggest that the drain pipe is jammed tight against something which is stopping it from normal expansion when (usually) hot water is passed through it. Unfortunately if that is the case it is either a case of living with it or stripping out the pipe box and freeing the restriction from the pipe then rebuilding the box with a bit more clearance on it.

 

[JCplumb]

There's a very recent thread on here on this very subject, do a quick search, it has been discussed at length 🙂

 

[Rodolphe]

Nice tiling!

 

[lame plumber]

why remove a working stack and spend money on solving a non problem. Now when the aav jams open and needs replacing youll have a tiling bill as well, sorry but I hate aavs they have their uses but an open stack has worked for 100 plus years with no gurgling etc.

 

[stevetheplumber]

for once i agree why did he cut it down should have tiled it in and left aav in loft where it can be got at , would have had lots of air round it and you wouldnt be able to here it

 

[craig james]

Thanks for all the replies, especially about ventilation. (I just tried to reply but my post was denied for some reason, so I'm trying again.) Can you confirm that it's normal for the tapping sound to be loud enough to be heard through the boxing-in? Also, is the gurgling sound when the final bathwater drains away to do with the AAV, or is there another cause? Or is it normal - I didn't notice it with our previous bath. Don't know if it's relevant but the distance between the pipebox and the bath drainhole is about 7 feet. There is no gurgling with the basin, the shower or the toilet.

 

[galaxy_plumbing]

by draining down you would create a vacuum so water would try to drain by gravity but sucking air and creates vacuum, when that breaks you get your gurgle. Can put some vent grill on the side of the boxing or maybe drill few holes in the tile?

Just my opinion.

 

[mike-c]

You will hear the tapping/creaking sound through the box. It is the same noise that is heard sometimes on heating systems when the pipe work is tight going through timber joists

 

[craig james]

You will hear the tapping/creaking sound through the box. It is the same noise that is heard sometimes on heating systems when the pipe work is tight going through timber joists

Thanks for all the replies. It seems the only real solution is to rebuild the stack back into the attic, both to give the AAV air and to stop hearing the tapping noise. Unfortunately, as the plumber severed the pipe to shorten it, the section where it can be joined again properly is via the downstairs kitchen! I see an expensive re-plastering and painting job... I'll confront the plumber on all this.

 

[PlumbBobBob]

you can get jointing pieces so no need to take right back to the kitchen

 

[snowhead]

It could be joined just below where the existing AAV is.
And /or possibly go out through the back or side of the existing box, unless it goes into your nextdoor neighbours!!

 

[lame plumber]

Thanks for all the replies. It seems the only real solution is to rebuild the stack back into the attic, both to give the AAV air and to stop hearing the tapping noise. Unfortunately, as the plumber severed the pipe to shorten it, the section where it can be joined again properly is via the downstairs kitchen! I see an expensive re-plastering and painting job... I'll confront the plumber on all this.

question is why did he take away the stack pipe, was he asked to? When dealing with him my advice is not to confront him as it probably means your nose to nose, not good if you upset him :46: why not ask his advice on the noise etc first and having listened to us, you know what you want to hear and can lead him in that direction and if you meet him halfway you may get somewhere. Also did he do the tiling, if not then prehaps the tiler should have installed a vent? it's not always black and white. have fun trying, don't end up with a throbbing nose from being confrontational, customers that are nice and polite to me get listened to and helped, the rest, well they are still waiting!

 

[TomLane]

Good point well made there. All too often a question is asked to other professionals by general public, they get mixed answers & end up being so confused & therefore wound up by the answers they confront the tradesmen responsible for the work in an unnecessary manner. A polite & courteous approach goes far further to the tradesman potentially being more agreeable to resolving the solution rather than walking away in defence.

As mentioned, explain problem with noise etc, then ask as to why the stack was altered (other than for aesthetics!). This can be done all quite civilly.

I'm not accusing the OP poster of being aggressive or anything similar. I just felt it necessary to highlight upon an issue that happens all too often for any future readers of this topic.

I myself always offer to rectify any problems/issues/complaints that a customer may have, within reason of course. I find this way the customer will recommend you more for being able to accept call backs etc rather than you having an attitude of "jobs finished, not my problem"

Hope you get this sorted.

 

[craig james]

Good point well made there. All too often a question is asked to other professionals by general public, they get mixed answers & end up being so confused & therefore wound up by the answers they confront the tradesmen responsible for the work in an unnecessary manner. A polite & courteous approach goes far further to the tradesman potentially being more agreeable to resolving the solution rather than walking away in defence.

As mentioned, explain problem with noise etc, then ask as to why the stack was altered (other than for aesthetics!). This can be done all quite civilly.

I'm not accusing the OP poster of being aggressive or anything similar. I just felt it necessary to highlight upon an issue that happens all too often for any future readers of this topic.

I myself always offer to rectify any problems/issues/complaints that a customer may have, within reason of course. I find this way the customer will recommend you more for being able to accept call backs etc rather than you having an attitude of "jobs finished, not my problem"

Hope you get this sorted.

Thanks for the further replies. My use of the word "confront" was not in the belligerent sense, but in the "approach" sense. In fact, my wife and I like the plumber and he's very conscientious. We do feel for him because it was his idea to shorten the stack for aesthetic purposes, and we had no idea of the effect this would have on the pipe. The bathroom saga has been going on many weeks because of tiling issues as well (the plumber commissioned the tiler) which have still to be sorted out by a second tiler the plumber is bringing in, and we've been very patient. I'm relieved to hear it's possible to join a new section of pipe on a severed section.

 

[Plum Bob 66]

Thanks for the further replies. My use of the word "confront" was not in the belligerent sense, but in the "approach" sense. In fact, my wife and I like the plumber and he's very conscientious. We do feel for him because it was his idea to shorten the stack for aesthetic purposes, and we had no idea of the effect this would have on the pipe. The bathroom saga has been going on many weeks because of tiling issues as well (the plumber commissioned the tiler) which have still to be sorted out by a second tiler the plumber is bringing in, and we've been very patient. I'm relieved to hear it's possible to join a new section of pipe on a severed section.

Sometimes function is not best over form, this being case in point. Possibly a far simpler solution that I believe has already been posted is to fit some form of grill into the tiling which both serves a purpose and possibly aesthetically pleasing

 

[Plum Bob 66]

Sometimes function is not best over form, this being case in point. Possibly a far simpler solution that I believe has already been posted is to fit some form of grill into the tiling which both serves a purpose and possibly aesthetically pleasing

That should have read sometimes form is not best over function..........too many bailys lol.