Mansard roof
A mansard or mansard roof (also called French roof or curb roof) is a multi-sided gambrel-style hip roof characterised by two slopes on each of its sides, with the lower slope at a steeper angle than the upper, and often punctured by dormer windows.[1][2][3] The steep roofline and windows allow for additional floors of habitable space[4] (a garret), and reduce the overall height of the roof for a given number of habitable storeys. The upper slope of the roof may not be visible from street level when viewed from close proximity to the building.
"Mansard Roof" redirects here. For the Vampire Weekend song, see Mansard Roof (song).The earliest known example of a mansard roof is credited to Pierre Lescot on part of the Louvre built around 1550. This roof design was popularised in the early 17th century by François Mansart (1598–1666),[5] an accomplished architect of the French Baroque period.[6] It became especially fashionable during the Second French Empire (1852–1870) of Napoléon III.[7] Mansard in Europe (France, Germany and elsewhere) also means the attic or garret space itself, not just the roof shape[8] and is often used in Europe to mean a gambrel roof.
Advantages[edit]
The mansard style makes maximum use of the interior space of the attic and offers a simple way to add one or more storeys to an existing (or new) building without necessarily requiring any masonry.[14][15] Often the decorative potential of the mansard is exploited through the use of convex or concave curvature and with elaborate dormer window surrounds.
One frequently seen explanation for the popularity of the mansard style is that it served as a method of tax avoidance. One such example of this claim, from the 1914 book How to Make a Country Place, reads, "Monsieur Mansard is said to have circumvented that senseless window tax of France by adapting the windowed roof that bears his name." This is improbable in many respects: Mansart was a profligate spender of his clients' money, and while a French window tax did exist, it was enacted in 1798, 132 years after Mansart's death, and did not exempt mansard windows.[16][17][18]
Later examples suggest that either French or American buildings were taxed by their height (or number of storeys) to the base of the roof, or that mansards were used to bypass zoning restrictions.[19][20] This last explanation is the nearest to the truth: a Parisian law had been in place since 1783, restricting the heights of buildings to 20 metres (65 feet).[21] The height was only measured up to the cornice line, making any living space contained in a mansard roof exempt.[22] A 1902 revision of the law permitted building three or even four storeys within such a roof.[23]
In London in the 1930s, building regulations decreed that "a building (not being a church or a chapel) shall not be erected of, or be subsequently increased to, a greater height than 80 ft., exclusive of two stories in the roof, and of ornamental towers". This was to stop buildings blocking the light, and effectively mandated mansard roofs for tall buildings.[24]
Transportation[edit]
The roof of two Victorian Railways hopper wagons resembled a mansard roof. The Australian Commonwealth Railways CL class locomotive also has a mansard roof.