Would you still say this if it was only for the kitchen sink?Your 110mm pipe is fine, the minimum size for an underground drain in your situation is 3" (82mm), as 82mm underground pipe and fittings are harder to get and usually more expensive 110mm is used.
Only a cowboy would bury 1½" or 2" pvc waste pipe under a concrete floor.
Would you still say this if it was only for the kitchen sink?
That is good to know but it does not say from where to where, & presumably only if it is buried at a certain depth as internal & external waste pipes often seem to have long smaller size runs.If a 40 mm pipe was in a channel in the floor then tiled over would this advice still be applicable?
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local