WHAT IS THE ROOF STRUCTURE LIKE ON A PREFA ALUMINIUM ROOF?

The attic can also be used as living space (Fig. 1):

Compared to a single-skin roof structure, a ventilated channel is added to the double-skin roof structure (counter battens). In this way it is then possible to provide thermal insulation between the rafters too. A double-skin roof structure should be preferred to a single one when considering future use of the attic (Fig. 2).

The attic is not used as living space (Fig. 2):

With this type of roof structure, the attic ceiling must be thermally insulated (complicated creation of an attic extension at a later stage).

The roof structure must comply with, or be adapted to, building physics criteria.