https://www.twitch.tv/staydryroof/about">https://www.twitch.tv/staydryroof/about. A high quality roofing system will have them set up around the edge of the roofline, where upright walls satisfy the roofing slope, https://safaybtd154370.dgbloggers.com/39976121/the-facts-about-stay-dry-roofing-revealed