Trench for Waste Pipe

[Clammant]

Hi,

Hope someone can help.

We are putting a downstairs toilet in our house and will be digging a trench for the waste pipe which runs under the kitchen floor and under the backdoor to meet the existing outdoor waste pipe via a new manhole.

Pretty happy giving it a go myself and had the OK from the building inspector to start digging. My only worry is cutting a hole through the foundation under the outer wall of the housefor the pipe. Can I just dig and cut through it? Any damp proofing issues?

Many thanks.

 

[bobasd]

youve got to first dig down to expose the outside soil drain pipe.
the bottom of that pipe is the invert and the invert determins all your digging depths and falls from the WC.
you should bewell under the DPC bed course for the breakthro.
dont go mad nocking out lots of bricks, just open up an easy hole for the 110mm pipe.
BCO's like lintels but your call.

 

[Clammant]

That's great, thanks so much for your help!