Wash hand space saver with self-closing waste valve 32 X 32MM

[Adsibob]

I'm considering adapting an old piece of furniture into a vanity unit by mounting a countertop basin on top of the piece of furniture. Directly under where I want to mount the sink, there are some drawers. The top drawer is about 8cm deep. If I lose use of that drawer, presumably i still don't have space to fit a normal U-bend in it? If that's the case, could I use this: https://www.screwfix.com/p/mcalpine-wash-hand-basin-space-saver-with-self-closing-waste-valve-white-32-x-32mm/863HP?tc=ST2&ds_kid=92700055281954514&ds_rl=1249404&gclid=CjwKCAjw9aiIBhA1EiwAJ_GTSmDfMhXLaYlhNgx6txgim_zmzk2dsN1hq7GHyA-mPwdJVZLRrUSSixoC7pQQAvD_BwE&gclsrc=aw.ds

 

Has anyone fitted (and lived with) one of these? Of the three reviews on screwfix's website, it looks okay, but just sounds too good to be true. If this works so well, why would anyone bother with a u bend? 

 

 

[Temp]

I'm not sure how reliable those are. Think they have a valve rather than a water trap.

 

There are more conventional shallow traps like this one but check thread sizes match your waste etc

 

https://www.amazon.co.uk/Wirquin-31000006-Siphon-Space-Basin/dp/B00JISJZOC/ref=asc_df_B00JISJZOC/?tag=googshopuk-21&linkCode=df0&hvadid=310135442117&hvpos=&hvnetw=g&hvrand=15151511845223287408&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=1006818&hvtargid=pla-523958478630&psc=1&th=1&psc=1

 

Also some metal are pretty shallow... price not so..

https://www.marflow.co.uk/product/basin-trap-shallow-p/

 

Edited August 4, 2021 by Temp

[Adsibob]

5 minutes ago, Temp said:

I'm not sure how reliable those are. Think they have a valve rather than a water trap.

 

There are more conventional shallow traps like this one but check thread sizes match your waste etc

 

https://www.amazon.co.uk/Wirquin-31000006-Siphon-Space-Basin/dp/B00JISJZOC/ref=asc_df_B00JISJZOC/?tag=googshopuk-21&linkCode=df0&hvadid=310135442117&hvpos=&hvnetw=g&hvrand=15151511845223287408&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=1006818&hvtargid=pla-523958478630&psc=1&th=1&psc=1

 

 

Yes, it is valve based. The downside of the Wirquin you've found (at least according to the reviews) is that it can be a little noisy. Also looks similar to the trap that came with @Bitpipe's floor mounted resin bath I believe, which he described as "worse than useless", although perhaps for a bathroom basin it's okay. Not sure

 

I think I understand how a bottle trap works, in that it uses a bend in the pipework to create a small reservoir of water that acts as a block to prevent nasty smells coming up. But I don't get the difference between all the different types of traps and their pros and cons. For example, would something like this work: https://www.screwfix.com/p/floplast-shallow-bottle-trap-white-40mm/19145

 

[Temp]

Cheaper source for the metal one..

https://www.victorianplumbing.co.uk/exposed-bath-trap-low-level-chrome-201911

 

And an ultra shallow..

https://www.ukbathrooms.com/products/clearwater-ultra-shallow-seal-p-trap.html

Edited August 4, 2021 by Temp

[Temp]

2 minutes ago, Adsibob said:

Yes, it is valve based. The downside of the Wirquin you've found (at least according to the reviews) is that it can be a little noisy. Also looks similar to the trap that came with @Bitpipe's floor mounted resin bath I believe, which he described as "worse than useless", although perhaps for a bathroom basin it's okay. Not sure

 

I think I understand how a bottle trap works, in that it uses a bend in the pipework to create a small reservoir of water that acts as a block to prevent nasty smells coming up. But I don't get the difference between all the different types of traps and their pros and cons. For example, would something like this work: https://www.screwfix.com/p/floplast-shallow-bottle-trap-white-40mm/19145

 

 

Yes if its not too deep.

[Temp]

The main issue with very shallow traps is that it's easier for the water to be siphoned out by water flowing elsewhere (eg when you flush the loo). An AAV can stop that if it's a problem.

[Adsibob]

Thanks @Temp maybe I will fit an AAV. Does that create any air tightness issues for the MVHR system?

 

I also wonder whether another solution might be to use a standard trap but locate it a bit further away from the sink's exit point so that I have more space for it. For example if directly under the exit point I have a right angled bend, that would take the waste water to the adjacent cupboard which is a cupboard rather than a set of drawers. Plenty more space there to locate a standard bottle trap. Or is that a no no because the trap must always go directly under the sink's exit point (as shown in the attached picture, which also features an AAV)?

 

 

[Temp]

I'm not aware of any issues with AAV and MVHR.

 

3 minutes ago, Adsibob said:

For example if directly under the exit point I have a right angled bend, that would take the waste water to the adjacent cupboard which is a cupboard rather than a set of drawers. Plenty more space there to locate a standard bottle trap.

 

I think that's fine. 

[Bitpipe]

1 hour ago, Adsibob said:

Yes, it is valve based. The downside of the Wirquin you've found (at least according to the reviews) is that it can be a little noisy. Also looks similar to the trap that came with @Bitpipe's floor mounted resin bath I believe, which he described as "worse than useless", although perhaps for a bathroom basin it's okay. Not sure

 

I think I understand how a bottle trap works, in that it uses a bend in the pipework to create a small reservoir of water that acts as a block to prevent nasty smells coming up. But I don't get the difference between all the different types of traps and their pros and cons. For example, would something like this work: https://www.screwfix.com/p/floplast-shallow-bottle-trap-white-40mm/19145

 

 

The trap I had was even worse than that, just concertina plastic pipe really.