Mansard Roof Styles

Straight

• The upper slope of a straight Mansard roof is not normally visible at ground level. They are designed with dormer windows set in the lower slope, which may be almost vertical. In addition to extra space, the dormers provide lighting and ventilation. A Mansard straight roof can also have two stories. One drawback of a Mansard roof is that the weight of snow accumulation can cause cracks and leaks from the roof's surface.

Convex

• The convex shape of the Mansard roof curves outward on the lower slope. The base of the convex roof is formed by a wide cornice supported by heavy brackets. Some convex mansard roofs are shaped like an "S", while others have a bell shape. This shape, as is the case with all Mansard roofs, adds interior space without the need for adding another story to the building. Convex Mansard roofs are often seen on courthouses with elaborate clock towers.

Concave

• The concave Mansard roof curves inward or can be flared. Some concave roofs have a steep angle on the lower slope. During the second half of the 19th century, a popular design for mansions and large buildings was an elaborate concave Mansard roof.