The Aqua Blocker is perfect if you want to seal a flat roof itself! I thus get 30sqm quickly and reliably sealed. The material bound quickly (sometimes too fast, so it also dries up during longer breaks). The material it saves the roofer! You just have to necessarily note the Technical Data Sheet! Incidentally, it is much more efficient than specified in Verbauchshinweis. Instead of the calculated 6 bucket I got loose from 4!