I'm aware that when we as landscapers lay patios the general rules are 2 courses below DPC or Air-bricks, But with so many people extending their homes and having bi-fold doors, I get asked a lot for paving to be the same height as the tiles indoors. Obviously gully's & drainage channels would be an easy choice to suggest (with falls away from house ideally) but what I would like to know is: * Am I allowed to pave at the same height as flooring indoors? * If I can, what protection do I install to stop breaching DPC? Not fussed if it simply shouldn't be done, just wanted clarification guys Cheers