The roof plane should be large enough and oriented as far south as possible. The east-west and west-facing roof planes are also suitable for solar panels. The slope of this plane should be 60 (+/- 15) degrees.

The roof can also be flatter, but then the collectors will have to be mounted above the roof. Trees that could obscure solar panels after 20-30 years should not be planted in front of the house. As collectors are light and as durable as the roof, they are suitable for practically any roof. If there is no space on the roof or it is too shaded, solar panels can also be placed on the wall of the building or on the ground.