Tried to clean a roof very similar to this this week. Conservatories (Sorry its the last picture on the link. Struggling to share a picture) The problem I had was I didn't have a ladder (Back at home.) Tried using customer step ladders that had different lenght legs (Shaking like a shitting dog on em) and I was struggleing to clean it. I'm going back with my own free standing ladder on Friday morning. The angle of the roof was lower that the one in the picture and it was a real bugger to rinse? Any advice?