Here too, it depends on the type and scope of the work planned. If it is just the roof covering that is being renovated, one roofer is required. If the roof structure is being renovated, a carpenter is also required. The same goes for conversions and extensions. In these cases, other trades such as dry masons, electricians, floor layers, etc. are required. Any changes to the building structure that differ from the most recently approved plans also require a planner, master builder or architect as the general planner overseeing the site plan, to supervise the work and obtain any building permits (see point 1).
Please note that for guarantee and quality reasons, each PREFA product may only be installed or mounted by a professional specialist company. Click on this link to find a PREFA installation company near you.