...uminous paint. Is there a decent product I could paint up the walls, slates, and cover the gutter to make it watertight ? The average stuff from Travis Perkins ain't going to cut the mustard, I don't think. Been quoted £5k to fibreglass it, but that seems.......extortionate. Is fibre glassing a job for the average peasant ? Obvious medieval design flaw here, which I can't do much about. Wide gutter, which narrows by the chimney, which gets blocked up with crap easily. Any ideas to sort it other than fibre glass, bituminous paint etc ? Thanks.