Hi, my neighbour are lucky enough to enjoy large gardens (about 32' x 125'). Drainage ain't the best and my garden is damp all through summer. My bodge job neighbour has had a great idea to slab what seems all of his garden. He's currently upto about 900' sq. I'm concerned about what this means for my drainage. Is he allowed to do this, seen as though the average drive now need planning for drainage issues?