Flat to pitch framed roof systems

Flat to pitch conversions completely transform the appearance of the building. In some cases, they are the only effective way of waterproofing the existing roof structure but do require a detailed structural survey to be carried out. This is to ensure that the existing roof structure or supporting walls are capable of withstanding the additional dead and imposed load or the loads which are transmitted from the new structure.

Solution

• Uses a completely new lightweight galvanised steel frame superstructure to fit over the existing flat roof. The framework provides support for a new pitched metal roof, which quickly clears rainwater from the area. The lightweight structure does not impose a high dead load onto the existing roof, although during the design process this extra load has to be taken into account to ensure that the structure can accommodate it.
• Can incorporate additional habitable space within the new roof structure. This will depend upon the result of the structural survey and the layout of the existing services and access.
• Can be further insulated with low-density mineralwool roll insulation on top of the old roof to improve u-values and reduce heat loss from the building.
• Allows for a standing seam system to be chosen for the new roof, especially where the pitch is low. For a greater pitch, a simple, through-fix trapezoidal profile can be employed.