Hi to all.I Have a customer who aswell as wants a new bathroom suite fitted also wants a toilet and basin fitted downstairs in the cloakroom.The plastic 4inch soil comes down in a cupboard,what i'm hoping to do is cut a tee in for the toilet and drill out the side of the tee for the waste connection for the basin.Do i have to get the alterations to the soil checked by the building authorities or can i just commence? Plus whats the easiest way to cut the new tee in? Would i have to disconnect all existing waste pipes to be able to get movement and make the cut? Any help would be grately appreciated,cheers