Would there be any problem

[George]

with the water piping arranged like this?

the main water pipe

[Phil L]

A bit more info George...How long is the diagonal run? Where is it? Why is it on a diagonal? Will it be boxed in?

I can't see any reason why not, it would just *look* weird, but if it's out of the way, there's no reason why you can't have it like that

[Andy Burns]

Is the diagonal actually going to be a smaller bore as the diagram suggests?

[meow2222]

no, if youre talking about supply. If drain, it would work but be more prone to blockage than would be best.

NT

[George]

Short

Under the stairs leading to the kitchen

Because thats the way I want it,rather than running along the whole lenght of the kitchen on top of the skirting

Probably?

I was thinking it might reduce the flow rate somewhat?

[Phil L]

I doubt it, that's MS paint for ya. :-p

[Phil L]

as long as a piece of string, or longer?

I had an idea it might be.

how?...there's no rules saying pipes have to be run diagonally or vertically, they just look neater that way, although if you ever go in a newbuild that is having plastic plumbing installed, you'll find that they go in all directions, IE wherever they fit, and into whatever shape the plumber wants to arrange them