What Is a Mansard Roof?

By Amanda Lutz Updated March 13, 2024

If you’re enchanted by the elegant style of Victorian homes and buildings with dormer windows and grand design, the appeal of a mansard roof is hard to ignore. While the roof style has been around for centuries and can be seen on many historic buildings, it’s not outdated and can enhance modern buildings and homes. Whether you’re interested in historic architecture or are considering the potential for a mansard roof on your home, there’s much to learn about this complex roof style. In this guide, we’ll explain what a mansard roof is, delve into the history of the style, and explore its advantages and disadvantages.


What Is a Mansard Roof?

Also known as a French or curb roof, a mansard roof is a hipped-gambrel roof that slopes on every side of the building. It combines the attractive double angle of a gambrel roof with the four-sided style of a hipped roof to create an appearance that’s hard to overlook. Mansard roofs can be tiled or shingled and often feature dormer windows. The roofing style is prized for its ability to expand interior space and increase natural light and ventilation.

Mansard roofs aren’t as common as many modern roofing styles but can be seen on Victorian-style and Colonial-style homes, apartment buildings, and farmhouses. The style originated in France in the 1500s and became more popular in the 17th century and during the Second Empire. While the style eventually became popular in European and American homes and buildings, it’s generally considered a symbol of French architecture.

History of the Mansard Roof

The mansard roof first appeared in Paris during the 16th century but didn’t gain its formal name until it was popularized in the 17th century by architect François Mansart. One of the most well-known architects of his time, Mansart became famous for applying classical details to various buildings. The mansard roof gained popularity because of its ability to turn attic space into an extra floor with ample living space.

During the regime of Napoleon III (the Second Empire), nearly 200 years later, the mansard roof gained a massive resurgence in popularity, beginning with the expansion of the Louvre. The Emperor sought out architect Baron Georges-Eugène Haussmann to remake Paris in a project that mandated mansard roofs throughout the city. This reconstruction of Paris exposed the rest of the world to the mansard roof style, and it was immediately adopted in Germany, Italy, England, and America.

In America, the Second Empire architectural style quickly became a standard for federal, city, and state government buildings and was eventually adopted for use in hotels and residential buildings. At the height of its popularity in the U.S., mansard roofs were found on many types of homes, ranging from mansions to various residential homes to stables.

As modern, less ornate housing designs became trendy, mansard roofs fell out of style and were rarely used for over a century. In the late 1960s, they made a reappearance in commercial architecture. While the rapid expansion of fast food chains brought welcome convenience to cities, the building of these structures on practically every corner was seen as a blight on cities and towns. McDonald’s introduced a new design featuring a double mansard roof to address concerns. While McDonald’s patented their design, many competitors adopted a similar style. Although many of these roofs aren’t true mansard roofing designs, their similarities reflect the original style.


What Are the Advantages of a Mansard Roof?

Today, modern single-family homes with mansard roofs aren’t considered common. However, the aesthetic and functional advantages make them ideal for cities and small homesteads with limited building space. For homeowners investing in a historic home or seeking a creative renovation to increase living space, mansard roofs can offer various benefits, including the following:


What Are the Disadvantages of a Mansard Roof?

While a mansard roof has much to offer, it isn’t perfect. The complex design requires more effort to build and maintain than other popular roof styles. Before setting your heart on a home with a mansard roof, explore the disadvantages you’ll be facing with this ornate roof style.


Design Variations of Mansard Roofs

Throughout the centuries, mansard roofs were adapted for use on various house types. As they were adopted in different locations, these roofs were altered to support alternative styles. There are four main styles of mansard roofs, each with distinct differences in shape and functional design: concave, convex, S-shape, and straight.

Concave

A concave mansard roof features an inward curve that flares dramatically at the outward edge. This style creates the sharpest angle and is the most reminiscent of traditional French homes. The inward curve of a concave roof makes dormer windows an impactful standout feature for those admiring the home’s exterior. However, it drastically reduces the available interior space compared to straight and convex mansard roofs.

If you desire the architectural flair of early French architecture and having extra space is a lesser requirement, then a concave roof may be a good option for your home.

Convex

A convex mansard roof maximizes interior space with a lower slope that curves outward, resembling a bell shape. This type of design is frequently found on courthouses and other governmental buildings. Like other mansard roof types, convex roofs often feature dormer windows. However, the rounded shape may be better accentuated with arched windows, which can add further elegance to the design.

While this style isn’t frequently seen in residential homes, it’s the style most likely to add the interior space you desire without requiring you to add another floor to your home.

S-shape

While sometimes classified as a convex style, an S-shape mansard roof combines the architectural styles of convex and concave slopes to create a roof with a distinctive S shape. While this type of rooftop is almost flat like the other styles, the lower slope begins with an inward slope at the top and then swells outward in a bell shape at the roof’s lower points.

This shape can offer more interior floor space on the upper level than a concave roof but will feature a narrow ceiling. Since this style has more curves and pitches than other styles, it’ll likely cost more to install.

Straight

The upper slope of a straight mansard roof has a very gentle slope, making the top appear almost flat. The bottom slope is exceptionally steep and often almost vertical, presenting a striking contrast. Dormer windows in the bottom slope often mirror the angular shape of the roof, adding aesthetic value and increasing natural light for your home.

The nearly flat top of a straight mansard roof can allow snow and other debris to gather and stress the roof’s structure with increased weight. However, altered modern designs and the use of modern roofing materials like various metals can help mitigate these concerns.


Our Recommendation

Mansard roofs evoke images of grand historical buildings, early French architecture, and lavish mansions, and they offer elegance and charm that can be applied to many home styles. As homeowners continue to seek options for expanding indoor space with a limited blueprint, mansard roofs have the potential to make a resurgence.

The different types of mansard roofs could be adapted to modern home styles and the functional needs of users, but despite their aesthetic appeal, they have certain drawbacks. Before embarking on any major home renovation project, weigh the benefits and drawbacks and determine whether a mansard roof style is a good fit for your location and climate.


What Is a Mansard Roof FAQ

What is the purpose of a mansard roof?

When mansard roofs were first invented in France in the 1500s, they were designed to increase living space. The steep lower slope of these roofs turned previously unused attic space into a livable extra floor. Today, a mansard roof is often chosen for its elegant design. However, the option for additional space could become a driver for this roof style in areas where minimal building space is available.

What does a mansard roof look like?

A mansard roof looks like a combination of a gambrel roof and a hipped roof. It features a double slope on all four sides of a building and is typically adorned with dormer windows. Its vaulted appearance is typically associated with elegance and classic architecture.

What is the disadvantage of a mansard roof?

A mansard roof has a few disadvantages that can make it difficult to obtain and maintain. Its complex shape makes installation tricky and costly and may require a specialized permit to install.

What is the difference between a gambrel and a mansard roof?

While a mansard roof is similar to a gambrel roof, the two have distinct differences. Both gambrel and mansard roofs have short, low-slope top sections and steep lower sections. However, a mansard roof has panels on all four sides of a building, whereas a gambrel roof has panels on only two sides.

Where is a mansard roof used?

A mansard roof can be used on various buildings, including residential homes, apartment buildings, and historic government buildings. They can also be found on older homes that featured the original style.