A mansard roof is a very distinctive type of roof which has a steep slope around the edges (typically around 80 degrees), with a much shallower slope in the middle. From ground level the side roof slopes are visible but the roof appears flat on top. The main advantage of this type of roof is that the majority of the roofspace can be used for accommodation and the overall height of the roof is much less than a normal pitched roof. Effectively the roof provides an additional storey. The other main advantage is that in the right setting they look wonderful. The roof can be designed entirely in timber, but often steel frames are provided to provide greater flexibility in the layout of the building.

We need the following information to design a mansard roof: .

a layout drawing or sketch of the property showing the outline of the building and the position of any internal loadbearing walls

Design information

All design work is carried out in accordance with BS5268 (The structural use of timber).

The calculations provided will be suitable for Building Regulation approval.