Hi, I would like some advice on the edge of my drive. When it was laid the driveway would have been over or close to the DPC and as a result a channel of 350mm was put between the house and the drive, which we have filled with slate chippings - see pic. We are having the house re-rendered and I would like to tidy up this channel by putting an aco drain down the side of the house and into the sewage system and get rid of the slate chippings. Firstly is this a good idea and secondly is there anything I need to be aware of when doing this?