How much does it cost to install a mansard roof?

Reviewed by Adam Graham remodeling expert. Written by Fixr.com.

Homes featuring a mansard roof have a unique appearance, enhancing the property’s curb appeal. Mansard roofs are a unique structure blending the gambrel and hip roof to create a full-sized attic. These roofs often include dormer windows, curves, and other decorative features that make them more difficult to roof. They can feature many materials, including asphalt, slate, tile, and composite.

The national average cost to install new roofing on an existing mansard roof is $20,000 to $40,000, with most homeowners paying around $30,000 to install 2,000 sq.ft. of composite roofing shingles on a mansard roof. This project’s low cost is $15,000 for installing 2,000 sq.ft. of asphalt shingles on a mansard roof. The high cost is $50,000 to install 2,000 sq.ft. of slate shingles on a mansard roof.

What Is a Mansard Roof?

A mansard roof is a unique roofing style that allows for a complete attic. It is sometimes known as a French roof or French Cove roof. It can be considered a hybrid of a gambrel and a hip roof. It extends from the top in all four directions like a hip roof. Like a gambrel, it changes pitch and roof direction from fairly flat to extremely steep. Also, like a gambrel, there are often dormer windows cut into the front and sides of the roof. However, mansards often curve in rather than straight down, giving them a more decorative appearance than a gambrel.

Because of the different pitches, curves, and dormers, mansards can be more expensive to roof than other styles.

Mansard Roof Cost Calculator

Mansard roofs are very unique. How the roof pitch changes and curves means you need more roofing material than the average roof. You also have higher labor costs for the installation because of these features. Adding dormer windows and required flashing means they are some of the most expensive roofs to install. Below are the average costs to replace 2,000 sq.ft. of roofing on a mansard roof using different material qualities.

Like any roof, mansards can use many materials, from inexpensive asphalt shingles to extremely expensive slate shingles. Asphalt and architectural shingles are two of the least expensive ways you can roof a mansard. For the mid-grade, architectural and composite shingles and tiles may be used, while slate shingles are the best quality and more expensive way to cover this roof.

Mansard Roof Pros and Cons

Mansard roofs are highly decorative and are unique to specific architectural styles, such as the Second Empire style. The benefit of using this roof is it gives you a full-sized attic. You can use the attic as a fully finished space, with the ability to walk across the entire space without dealing with a sloped ceiling overhead.

However, despite the curb appeal and increased interior attic space, mansards have some drawbacks. The top of the roof does not have much of a pitch before it becomes an extreme pitch. This can make it hard to remove snow in the winter from the top. You often cannot see the top of the roof from the road, making inspections difficult. The cost of the roof is usually higher due to the pitch, making installation more difficult and increasing the amount of material needed. The dormer windows included in the roof and the inward curve make it time-consuming and expensive to roof.

Additional Considerations and Costs

• Lifespan. The lifespan of a mansard roof is dictated by the materials you install on it. This can range from 20 to 200 years.
• Maintenance. Maintenance is also determined by the materials. Generally, roof inspections and gentle cleaning are all that are regularly required.
• Flashing. Your mansard roof requires a lot of flashing. Flashing is installed around protrusions, such as chimneys and dormer windows. Flashing costs $15 to $25 a linear foot.
• Roof deck. If your mansard roof is old or you are using a heavy material that requires a new deck, you have additional costs of $800 to $2,800 on most roofs.