Couple of easy(?) waste questions

[Multiplex]

Just a couple of things I'm struggling with.

Is it okay to use an anti-vac bottle trap instead of an S-trap?

Can two basins and a shower be plumbed into the same 32mm waste pipe that leads to the soil stack?

I'm replacing my basins at the moment and need to make sure that what I'm doing will work properly.

Thanks!

Simon.

 

[Newboy]

No problem with the bottle v s trap

Shower should be 40mm not 32mm

 

[ChrisR]

2 basins alone should be 40mm if you ever use them together or the run is over 1.2m!

Water will go down any size pipe. Obviously it depends on the length and slope, and what hair etc is involved.
A slow shower waste means you're paddling in tepid water

 

[ricarbo]

There are maximum recommended lengths for waste pipes connecting to stacks. Exceed these and you risk the water being sucked out of the trap, leading to drain smells in the room. The antivac trap is a 'cheat' to successfully get over this problem. Waste pipes should be installed with a two and a half degree fall. Too shallow means it blocks more easily, too steep means the pipe gets scoured and the flow rate is too high - might make the trap more prone to being sucked out.

 

[Multiplex]

This is what the builders did. The house is only a year old so is it ok with the regs to plumb a shower trap with a 32mm pipe?

To the right of the basin plumbing the waste pipe is 40mm, then they reduced the rest of the pipes to 32mm for some reason.

What I want to do is cut back the 40mm pipe, and plumb two basins in using 32mm pipe. This is so I can hide the waste pipe in the wall which I intend to tile over.

Would that work?

Simon

 

[Bahco]

Use solvent weld waste pipes if you are burying them to ensure no leaks.

2 basins sharing the 32 mm shouldn't be a problem if you use one at a time.
I would go with a separate 40 mm waste with its own connection into the soil stack though.

 

[Multiplex]

Help! I've got a problem. If you see the T-join in the bottom right of the picture, it turns out the pipe to the shower is 42mm, and the pipe up to the basin is 32mm, and the pipe to the right measures between 52mm and 55mm.

I can't seem to find any fittings for a 52mm pipe anywhere?! Screwfix or B&Q don't stock them. Is this something I can get down at the plumbcenter because it seems a bit of an odd configuration to me.

Is this normal?!

Simon.

 

[Multiplex]

Ok, it must be a 50mm pipe. I've looked it up now!

Simon.

 

[ricarbo]

Obviously you haven't finished yet, but I was a bit alarmed to see the electrical junction box, you wouldn't want that to be under the basins!

 

[Multiplex]

Why, what's wrong with the junction box? It's okay to have a socket and a plug under the kitchen sink according to the people that replied to my question last year:

//www.diynot.com/forums/viewtopic.php?t=16328

Simon.