Plumbing sink waste into SIDE of soil pipe

[Amondeggs]

I am renovating our bathroom and have moved positions of toilet and sink. The sink waste was plumbed into the soil pipe downstream of the toilet and entered at the top of the soil pipe. To reposition the toilet I have shortened the 110 mm soil pipe but left the section where the sink waste entered in downstream of the of the toilet. I have rotated this section through 90 degrees so that the 32mm connector is on the side of the soil pipe. Then I have run the sink waste (32mm) pipe under the floor and into the side connection of the soil pipe. I want to know if the method is acceptable? I am aware from what I have read that siphoning may be a problem and that the water am be sucked from the sink trap? Would the fitting of an anti siphoning trap to the sink solve this problem? Once connected the floor will be tiled over so I want it to be bomb proof.
The soil pipe I am talking about is in a upstairs bathroom, in a modern house (13 years old) it is vented from the top of the pipe and the run from the toilet to the vertical drop is only about 3 foot. Please see the photo below.




Thanks in advance for any advice given. Cheers steve

 

[Whl4852]

What's the shower hose doing in the 32mm, testing out? Welcome to the forum by the way

 

[lame plumber]

1. bin the push fit and use glued joints.
2. bin all your lovely self blocking elbows and use straight runs and swept elbows
3. plan for the worst were possible and have a rodding acces if possible
4. if you leave it as shown dont tile use vinyl

 

[Whl4852]

Personally I would fit a non return where it enters the 110mm foul! :30:

 

[Amondeggs]

Yes just testing it out

 

[Helpfulplumber]

32mm is a bit small for a shower, if you have a combi boiler or a power shower you need 40mm,do it now before you shower with 40mm of water round your feet!!!

 

[turnpin]

In my own opinion there is obviously going to be a problem with induced siphonage also push fit waste fittings under the floor not good also too many bends inceasing the risk of blockages and no provision to rod the pipes if required .Hope you don't mind constructed critism best of luck regards turnpin🙂

 

[Helpfulplumber]

32mm is a bit small for a shower, if you have a combi boiler or a power shower you need 40mm,do it now before you shower with 40mm of water round your feet!!!

Sorry its not for a shower to many cans

 

[Whl4852]

32mm is a bit small for a shower, if you have a combi boiler or a power shower you need 40mm,do it now before you shower with 40mm of water round your feet!!!

Think it was the basin waste in 32mm

 

[Amondeggs]

Ok thanks for all the replies,

so I need

to use glued joints not push fit, change the 90 degree elbows for swept ones, fit a non return valve
but apart from that is it ok?

Is it ok to have the sink waste enter the soil pipe at the side?

and will the non return valve and anti siphoning trap stop the sink trap from emptying? Cheers

 

[lame plumber]

bin the elbows were posssible, water likes staight lines

 

[kozak1968]

Your be long gone before there is a problem... If it siphons fit a siphonic trap.

 

[Amondeggs]

Your be long gone before there is a problem... If it siphons fit a siphonic trap.

Ok thanks for that, I think I will fit an anti siphoning trap now then,

will change push fit for glued and use swept elbows.

do I still need non return valve? Are these generally reliable? As I'm tiling over?

 

[kozak1968]

Fitted strap on boss to the side like you have done many times before and have never had any issues. To be honest you wont need a siphonic trap IMOH

 

[Helpfulplumber]

Siphonic trap, that's a hammer horror film?

 

[Mike Jackson]

Don't fit a non return valve under the floor as you won't be able to get to it. Use a HepVo valve on the basin instead of a normal waste and that will act as an air inlet as well.

 

[Amondeggs]

Don't fit a non return valve under the floor as you won't be able to get to it. Use a HepVo valve on the basin instead of a normal waste and that will act as an air inlet as well.

Ok, yes that does make sense. Thanks for your reply 

does the hepvo fit in addition to the trap?

also will I still need a no siphoning trap with the hepvo valve?

Oh yes I have a landrover too lol

 

[ne1ls0n]

glued fittings all the way!! mcalpine if you have to, never push fit waste though, seen too many leaks etc.

 

[tom609]

why not use a junction instead of the bend and a reducer into the junction

 

[Whyme]

Hair felt on the pipes..Nice to see..:smile5:

 

[tweakyboy]

Ok, yes that does make sense. Thanks for your reply 

does the hepvo fit in addition to the trap?

also will I still need a no siphoning trap with the hepvo valve?

Oh yes I have a landrover too lol

The HepVo valve is a trap which allows air in when it is needed. So it will be anti siphoning but there is no water in the trap to siphon out!

 

[stratplus]

What's a non- return valve on waste pipe? Do you mean a hepvo ?

 

[Amondeggs]

The HepVo valve is a trap which allows air in when it is needed. So it will be anti siphoning but there is no water in the trap to siphon out!

ok, that sounds brilliant, thanks

so I will fit hepvo under sink,
replace push fit with glued joints,
And change to swept elelbows

job done,

thanks to all that have helped me , really appreciate it