Extending kitchen over outside drain

[Newboy]

Hopefully the existing gully connects onto the sewer via a branch. If the gully is in plastic, chances are that it's push fit. If so, leave the branch in place, remove the gully connection and bring to surface in 110mm.

How far from the surface (island) position is the sewer (laterally and vertically)?

 

[Bobbybingham08]

Yes the existing gulley does branch onto the sewer and is plastic. House built in 1992. The kitchen waste connection on the island will be about 1.5m into the house from where it is now. There is plenty of room for the fall.