longest run for 4inch soil pipe

[plumber89]

hi ive got to fit a wc in someones walk in wardrobe, but it involves running 4inch soil quite a distance, is it true the longest u can run 4 inch soil to the stack is 6 metres?( this is horizontal no verticals) and a 1 in40 to 1 in 110 drop is needed?
cheers

 

[GQuigley67]

6m is the limit yes, you can fit a saniflo or macerator same thing really

 

[plumber89]

ye was looking at that have fitted them in the past but customer is not keen on the noise, as it will be a ensuite and its in a block of flats, so if its used in the night dont spect neighbours will be happy, does this 6 metres shorten if i have to use bends? or is it still ok?

 

[GQuigley67]

how many bends are we talking about ? and what type of bends ? you dont want to be causing too much restriction in the pipework could lead to problems.

 

[plumber89]

hmm would be a bend about .75m from toilet, then another one 2.5 metres then another run of 2 metres then in the stack

 

[GQuigley67]

use 45 degree bends if you can to help the flow of water