UK Plumber Forum

[drzygote]

Hi
Im a punter who needs a second opinion please.

We had a kitchen fitted in a new house. The sink previously had a roughly 1.5m pipe going to the main stack and it had quite a visible fall on it. The fitter replaced the whole thing and has put in a pipe that has a very minimal fall on it, very hard to even see it at all. It slopes very gently down in the direction of the stack, a few degrees at the most.

I raised it as an issue and am being told that its fine, as long as it doesnt tilt towards the sink that it should be ok.

I am dubious, I can only imagine that stuff will build up in that pipe and it will eventually leak or get caked with debris.

Does anyone have any experience with this?

Thanks in advance

[REDSAW]

Hi,
The minimum fall for a 42mm pipe is 18mm per m. Maximum, 44mm per m upto 3m in length. so, in your case 27mm fall is fine!
whats more important is adequate clipping to prevent sagging where debris will collect, hence fitters suggestion.
That will be norm in all new house builds as its to code, what will give problems is folk stuffing coffee grinds rice and fats down the plug-hole!

[drzygote]

Thanks for that. When you say the minimum fall, are those according to building regs? Ive measured it and its roughly 10mm fall over the space of 1 metre.
I think it needs fixing

[REDSAW]

yes, it will be a regs requirement in suitable conditions but tbh no one will pursue it.
cant you raise ther sink trap?