Waste run for double bathroom sinks

[leenowell]

Hi All,

I am fitting a unit in our bathroom which has 2 sinks on it. Rather than have a trap for each which takes up space in the cupboards underneath, I wa s thinking of routing the wastes to a central point behind the cupboard and have a inline trap there. This would essentially have and elbow to connect into the sink waste, route the pipes behind the cupboard and then to the t rap. However,.... my plan seems to be flawed...

1. I can't find any elbows which have a screw fitting on one end to connect onto the waste and a pipe fitting on the other
2. The inline trap assumes a horizontal run however, once I have connects t he 2 pipes (one from each sink) to a tee, I would then require a vertical p ipe to go into the trap.
3. If I use a normal trap to get around (2), I can't find a straight coupli ng which has a pipe fitting at one end and then a male thread the other to take the trap.
4. I looked at the kitchen traps for a bowl and a half sink but the sinks a re too far apart and it results in even more pipework in the cupboard.

Seems like this is may not possible/ advisable. What do you think?

thanks

Lee.

[TMH]

I don't think they exist. Why would they make one?

I don't think they exist

I don't think they exist

If you can get threaded thingys to connect to the wastes maybe solvent weld?

[tabbypurr]

n have a trap for each which takes up space in the cupboards underneath, I was thinking of routing the wastes to a central point behind the cupboard a nd have a inline trap there. This would essentially have and elbow to conne ct into the sink waste, route the pipes behind the cupboard and then to the trap. However,.... my plan seems to be flawed...

ct onto the waste and a pipe fitting on the other

the 2 pipes (one from each sink) to a tee, I would then require a vertical pipe to go into the trap.

ling which has a pipe fitting at one end and then a male thread the other t o take the trap.

are too far apart and it results in even more pipework in the cupboard.

I was advised not to do that as you end up with a section of untrapped pipe , from which you'll get pongs. Nevertheless it is sometimes done.

NT

[newshound]

IMHO the risk of pongs is negligible for short runs, especially if on a decent slope. Often done beneath kitchen worktops for dishwasher / washing machine / sink. But, as you have discovered, you may require a certain amount of ingenuity.

[PeterC]

No need for 2 traps for close items - any 'feedback' will be from the top anyway. I had a similar problem - 2 traps on a 1.5 sink unit took up all of the top shelf due to the awkward route. I fitted a Hepvo 40mm waste, so no water in the trap and no possibility of wind blowing up it. Note: it doesn't like hot fat! A Hepvo will work when vertical as well:

[Brian Gaff]

So if the trap cloggs up you end up with water coming up the plug hole of the other sink then? Brian

[Tim+]

Why would you want to pour hot fat down a drain? Even rinsed down with plenty of detergent and water, it will still congeal in your drains. Very bad idea.

Tim

[The Natural Philosopher]

well of course with enough alkali or detergent, it wont. and what else should one do with it?

[John Rumm]

Separate traps for each sink is really the best way to go IME. Saves having the output of one feed up into the other sink etc.

[John Gardener]

Put it in an empty tin, let it congeal, put that in the bin.

[Tim+]

That may clear some of the stuff lying in the bottom of the drain but not fat that congeals on the sides.

This, or just wait for it to set in the roasting pan then wipe it out with kitchen towel.

Tim

[Muddymike]

I used two bottle traps. They are neater and take less space

Mike

[Bod]

[Bob Minchin]

looks like toolstation 19305 or similiar wll get you to round pipe from a threaded fitting with the application of a hacksaw, then into multifit components to the trap.

[PeterC]

/I/ wouldn't! Had to replace a trap that had been filled with fat and then ripped apert with sharp-ended curtain wire. If fat is fully emulsified it shouldn't congeal.

[Harry Bloomfield]

The Natural Philosopher wrote on 16/05/2017 :

Dear, oh dear...

Likely it is against the law anyway, but why put it down a drain at all, where it would congeal and block the drain? Both your drains and the public ones.

Depending on the amount, we pour it in empty tins, or when cool into empty plastic milk containers then once solid, into the bin.

[Roger Hayter]

You can certainly get straight 32mm female solvent weld to male or female pipe thread (which fits the 32mm traps). Combined with a 90deg spigot bend, these makes a fairly compact elbow to male thread adapter. I can't see any problem with what you are doing. BES solvent weld 32mm has all these fittings.