Soil pipe modifications for fitting a conservatory. Possible Durgo valve

[himagain]

Hi all

My first post and I'm hopefully looking for some advice.

I'm having a conservatory fitted and need to sort out the soil stack. Im going to internally plumb the sink and bath but its the toilet waste I'm struggling with. I've been told a durgo valve will work. Im able to move the toilet probably 6 inches to the left if needed.

At that moment the toilet exits and there is a 135 degree bend in the wall to the stack. I need to somehow in fit a tee and get it back to an internal vent pipe. Ive spent ages looking at what joints/pipes I need and seem to be stuck. There just doesnt seem to be fitting.

Any help or advice would really help me

Thanks in advance

David

 

[AWheating]

you may need to take the stack inside below the floor level of the upstairs and the up the corner next to the toilet as drawn, then dergo or vent tile in loft space would be best. what room is downstairs?

 

[himagain]

The kitchen is below so coming down wouldn't be ideal. I thought about going under the floor, however the joists run across left to right so it would weaken them some what. Does the drug have to be 110mm?