Washing machine waste

[NotSureAboutDIY]

Hi All
Can anyone give advice on plumbing the waste for a washing machine?

I've checked the idea of using a pipe out to an external drain and thats a no go as the only available drain is water run off not foul waste.
The foul waste isn't that trackable as it runs in the wall via a 32mm pipe so its not obvious where it could be joined externaly.

I can T onto the foul waste at the wall point but the previous owners attempts to do this caused back washing to the point where the w/m hose was inserted into the 40mm plastic waste pipe (though he didnt have a 600mm drop and u bend type arrangement)

my wall point is roughly 600mm from floor height
dropping to 410mm over 1.4m
and is about 700mm from the washing machine.

cheers in advance

 

[Fluffster]

Are you near your kitchen sink trap?
Pete

 

[NotSureAboutDIY]

Are you near your kitchen sink trap?
Pete

well the wall point is the waste point for my sink (which is currently directly above it via u bend), I was hoping to move the sink about 1.2m to the side and use a long angled waste back to the wall point with a T join for the washing machine comming in the other way?

 

[Fluffster]

You could purchase a trap with a washing machine waste connection and extend the hose pipe you then have the safety of a trap preventing foul odours.

From the previous owners exp the waste pipe may also be clogging up.

Pete

 

[NotSureAboutDIY]

You could purchase a trap with a washing machine waste connection and extend the hose pipe you then have the safety of a trap preventing foul odours.

From the previous owners exp the waste pipe may also be clogging up.

Pete

most of the traps Ive seen suggest a 600mm drop before the P/U or whatever bend this means that the outlet part is at a very low level, this is fine if you can go outside to an external drain but I dont see how this could connect to the inset wall waste (which is at around 600mm itself

 

[NotSureAboutDIY]

Ive decided to chisel the old waste pipe out of my wall as
1. its only 32mm for both kitchen sink and wmachine
and
2. it's totally level for much of the run.

Ive found where the waste attaches to the main foul downpipe from upstairs and hope to put a 40mm T input.

can anyone advise on suitable drops for sinks and washing machine wastes, Ive heard 1 in 40 mentioned before.
and is it wise to have sudden drop and near level runs as my current pipe appears to?
also any guidance on building regs for connecting waste to the soil stack could be handy, I was planning on adding a swept 40 T onto the stack (for both my washing machine and sink waste) and have seperate stand pipes for each (though with more like a 500mm drop for the washing machine)

Cheers in advance and thanks for the tips so far!

 

[NotSureAboutDIY]

not an entirely overwhelming response
still never mind if anyone is curious about similar issues I found some useful details in the planning/building regs H
-
http://www.planningportal.gov.uk/uploads/br/BR_PDF_ADH_2002.pdf
-
my soil stack appears to be steel which isnt funny for adding new branches to so that ought to be a challenge

 

[Fluffster]

Drill the soil pipe out and buy a plastic boss as they asre much cheaper then use mastic to seal the joint.

Do not use hammer action or u could crack the pipe.
Pete

 

[NotSureAboutDIY]

Drill the soil pipe out and buy a plastic boss as they asre much cheaper then use mastic to seal the joint.

Do not use hammer action or u could crack the pipe.
Pete

Cheers for the advice fluff, sounds logical.
is it not possible to join two (sink and Wmachine) appliances at the single point on the steel boss via a Y splitter or swept T?

 

[Fluffster]

Yes a y if you can using at least 40mm pipe.
Make sure you connection is not close to or opposite the wc boss as this would cause cross flow.
P

 

[NotSureAboutDIY]

Yes a y if you can using at least 40mm pipe.
Make sure you connection is not close to or opposite the wc boss as this would cause cross flow.
P

cheers fluff
no probs with WC or opposing flows as this is the only branch on this floor.

Ive got a Steel boss in my front wall
a short run in the wall (600mm) where I'll try to fit the T
followed by a 90 turn, followed by the long run to sink (wmachine right next to front wall) which totals 3.1m.
From the regs I think I'll need a 50mm pipe (just) for the sink (although the trap can remain 40) and only 40mm for the wmachine.

can you get 50/40mm Y or Ts?
what type of waste pipe would you suggest to connect to steel and for running in the wall?

I was assuming the solvent weld might be best but Im not sure how well it'll connect to steel...

 

[Fluffster]

Maximum run of 40mm pipe is 3m so you will have to go up to 50mm just enlarge at after each appliance
You will find 50mm fittings in all forms.
Do u mean attaching onto a sttel pipe as in straight coupling/
Use o/door silicone to seal not solvent weld
P

 

[NotSureAboutDIY]

Maximum run of 40mm pipe is 3m so you will have to go up to 50mm just enlarge at after each appliance
You will find 50mm fittings in all forms.
Do u mean attaching onto a sttel pipe as in straight coupling/
Use o/door silicone to seal not solvent weld
P

Cheers for the tip for the join onto the stack, I will keep in mind when fitting.

my local plumbers merchants suggested I use a self tapping bergin drainaway kit instead of a p bend for my wmachine, this has an air valve (like some of the hepvo stuff) and negates the need for a trap on the washing machine, if this is acceptable it really simplifies the design (as it does away with the need for a T or Y onto the stack join and fits flush with the space I have).

The actual length of the branch is very close to 3m (touch and go with corners if its just over or under) due to kitchen unit service space it would be handy to stay down on 40mm if possible, would a slightly increased slope from the 18mm min (say 25mm per m be adviseable?
is the 3m guidance or requirement?
does the antisiphon valve at the other end of the branch help/replicate an aav?

cheers again for the advice, one day I hope to have a usable kitchen and hopefuly that day will be before the missus leaves me for a bloke with a sink

 

[Fluffster]

Do not increase the fall too much or you could induce syphonge of any traps.
The 3m rule is a water regulation.
If you can tap into the waste with with the device the merchant advises go for it.

Antisyphon units are not to be confused with an Air Admittance valve
P

 

[NotSureAboutDIY]

Do not increase the fall too much or you could induce syphonge of any traps.
The 3m rule is a water regulation.
If you can tap into the waste with with the device the merchant advises go for it.

Antisyphon units are not to be confused with an Air Admittance valve
P

I thought so (the AAV is to do with controlling air into the stack at the top?) cheers fluff I'm looking on course, can you advise: if you use antisiphon valves (like hepvo) instead of traps on the whole branch are the 3-4m 40-50mm rules less relevant (I understand theyre to do with stack siphonage issues)the hepvo site kind of suggest they are but the regulations do not mention them at all?

http://www.hepworthplumbing.co.uk/hepv7.htm

1 Full bore flow will no longer cause siphonage where HepvO® is fitted to all appliances. Full bore flow provides better self cleansing which means that smaller diameter waste pipe branches can be considered in many applications.
2 Anti-siphon piping and valves are not required for waste appliances.
3 Auxiliary venting is not required for ranges of waste appliances.
4 No maximum limit on waste pipe slopes.
5 Branches connecting waste appliances to a common pipe do not need to be swept at 45 degrees.
6 Where necessary tight radius bends can be used, without fear of siphonage or compression.
7 Waste pipe configuration, such as parallel branches, will not cause siphonage or compression problems, therefore there is no need to increase pipe size.

also the suggested benefit of tight bends in the branch is interesting to me as my design has some pipe set in the wall (behind washing machine) and a tight jink so the same pipe can then run flush to wall...

Cheers again fluffster I realise a little knowledge can be a dangerous thing so running these by you has really helped!