They are going to replace sheet metal at the roof. Wiklunds Tak-Fasad-Vent
need to calculate how much material they will need.
At a drawing they could see the measures from above (6 meter x 4,5 meter, picture 1). In the reality the roof is leaning with an angel of 30 degrees (picture 2).
How many sheet metals do they have to order to cover the roof, one sheet metal is 1 m x 6 m?