What Is a Mansard Roof, Anyway?

Standing on the sidewalk looking up at a Victorian home, you probablyknowthere are major design elements that make it different from other kinds of houses. But could you name them?

One conspicuous characteristic that sets it apart from the rest is its roof. If you’ve ever bopped along toa song of the same name by Vampire Weekend,你可能会有一个想法的这种屋顶is called: a mansard roof.

For amateur architecture buffs, they can feel like a “you know it when you see it” type of trait. But there’s more to mansard roofs than meets the eye. Here’s how mansard roofs came to be — and how to tell which roofs are mansard roofs.

A mansard roof, by definition, is a roof with four sloping sides. Unlike a two-sided gabled roof (the kind of roof that a kindergartener might draw), a mansard roof is hipped, which means that its four sections, of roughly the same shape, tilt downward toward the walls. Two opposing sides of a mansard roof usually have a steeper slope than their adjacent faces.

Mansard roofs can be tiled or shingled. They often feature dormer windows, letting light into the attics of buildings and allowing for additional living space to be created on the top level.

The mansard roof style can be traced back to buildings in Italy and England in the 16th century, though the Louvre, built in 1793, is often cited with its first-ever appearance. The look was eventually named for the French Baroque architect François Mansart, who topped Parisian hotels and countryside chateaus with the roof, perBritannica.

Later, the roof shape became popular in Victorian architecture. Second Empire homes in particular, a type of Victorian popularized in the U.S. the mid-19th century, were defined by their distinctive mansard roofs. These roofs were revived in France during the reign of Napoleon III, also known as France’s Second Empire, which gave the style its name.

Second Empire design was employed in major public buildings in America. TheCharity Hospitalin New York City and theCorcoran Gallery of Artin Washington, D.C., both completed by architect James Renwick, served as catalysts for its popularity in civic buildings. According to “The Field Guide to American Houses,” the architectural style fell out of favor after thepanic of 1873and the economic depression that followed.

There’s one main advantage to a building with a mansard roof: itmaximizes the spaceof a building’s attic, allowing for an easy way to add another level of living space without requiring more siding or masonry.

“The upper boxy roof line was considered particularly functional because it permitted a full upper story of usable living area or attic space. For this reason, the style became popular for the remodeling of earlier buildings as well as for new construction,” writes Virgina Savage McAleester in “A Field Guide to American Houses.”

Some experts argue that mansard roofs were created in part to circumvent zoning restrictions. AParisian lawenacted in the late 1700s, for example, restricted the height of buildings to 65 feet. At the time, building heights were only measured up to the cornice line (or below where the roof began), meaning that the living space within a mansard roof didn’t count toward the total measurement.

Could you pick a mansard roof out of a lineup armed with this knowledge? Try it outon your next walk.