A roof laserscan created from 57 different scanning positions. Every single detail of this roof has been scanned with millimeter accuracy. The resulting 2.2 billion points were used for creating CAD drawings and a detailed deviation report. Water drains were also mapped, as well as many other important technical details. A colorized deviation report enables us to identify problematic zones where rainwater is unable to easily run down the drains. All this scandata and the generated 3D model can be used for more in-depth computer simulations regarding the weight distribution and draining of rainwater.