Slope of soil pipe

[davphi338]

Hi,

I am considering options for an extension at the rear of my property. I want to move the soil stack from the rear to the side of my propery. The extension will be single storey with a pitched roof. I am hoping to run the wastes for the toilet, bath, shower etc from the existing bathroom through the void in the pitch roof and around to the soil stack. I was just woundering if there are any regulations to the min amount of fall of the wastes. The run will be about 5m and the fall approx 400mm.

thanks for any advice

 

[ChrisR]

Once you're off the fittings the normal recommendation is 1 in 40. Off the wc it's good to start steeper, about 1 in 24, but after the first couple of feet don't go too steep, or it doesn't flow properly.

 

[davphi338]

Looks like the slope won't be a problem then. Is there any problem with putting in a 90 degree bend to get from the rear of the property to the side where I plan to put the soil stack.