Mansard Roofs: An Intro

Published: Oct. 26, 2018

A mansard roof, also known as the French roof or Curb roof is a type of roof that has two slopes on every side, with the lower slope much steeper than the upper slope. The design is a hybrid between a hip roof and a gambrel roof. The mansard roofing style is gaining popularity due to the roof’s ability to provide a versatile living space.

History of Mansard Roofs

The earliest known mansard roof dates back to the 1550s. However, it was not until the early 17th century that the Mansard style of roofing was popularized. Mansard roofs gained even more recognition as a fashionable roofing choice during the second French empire (1852-1870) and have become a significant part of French architecture ever since. In the 19th century, Mansard roofs became popular in many European and North American buildings. The roofs were common not just in large structure but were used in private residential spaces too.

How are Mansard Roofs Built?

As with any project, the first step involves planning and buying all the supplies. The area under consideration needs to be prepared for the machinery and building work. The next step involves fixing the common rafters to one ridge board and then fixing the other rafters in place once the ridge has been elevated. The outside rafters are placed at the highest plate of the wall and then nailed into place. The same process is repeated for all the sides.

The next step involves securing the ceiling beams in place and then the area is covered with sheathing. The upper extension is then built using vertical rafters that are placed within the ridge board’s boundaries. The last step of building the mansard roof consists of attaching the sheathing material to the common rafters using nails. Areas having vents and valleys need to be covered using flashing.

Once complete, an undercoating material can be placed over the entire surface before it is covered with shingles. Wooden shingles and slate tiles are generally used to make mansard roofs.

How Long do these Roofs Last?

Provided that the mansard roof has been properly installed and can withstand snow and drain rainwater effectively, the roof can last a century. Metal roofing options like copper shingles prove to extend the life of the roof as they can withstand damage effectively. On the other hand, asphalt shingle based mansard roofs tend to last 20 to 30 years on average.

Advantages of a Mansard Roof

  • Extra Space:

Due to their vertical bottom slope, mansard roofs offer more attic space as compared to a gable or hip roof. The loft area can easily be turned into a small bedroom. The loft space also allows more natural light creating a sense of openness.

  • Aesthetic Appeal:

Mansard roofs make buildings look elegant and aesthetically pleasing, after all, they were a significant part of French architecture and can be designed and furnished in multiple ways to offer more space and provide a sophisticated look.

  • Expandability:

Mansard roofs can easily accommodate additional floors on top. This proves to be favorable for homeowners that may wish to add more floors in the future. This not only saves on costs but also provides peace of mind.

  • Cost Savings:

Mansard roofs help cut costs since homeowners do not have to worry about building separate rooms but can rather utilize the loft space. Heating costs are also reduced since the design of the roof allows even distribution of heat.

Drawbacks of a Mansard Roof

  • Installation Costs:

Mansard roofs are complex roof systems that incur high installation costs. To ensure the investment pays off, it is important to find a roofing expert who is familiar with installing quality mansard roofs.

  • Weather Resistance:

Due to the low pitch of the top part of the roof, mansard roofs are not suitable in areas prone to extreme weather. The flat slope is not the best at draining water from heavy rainfall and this can result in leakages.

  • Maintenance and Repair:

It can be hard to find a roofing expert who is proficient in mansard roofs. This is why the cost of maintenance and repair is high. Dormer windows also bring up the maintenance and repair costs.

  • Local Law Challenges:

Depending on the area, it may be a challenge to get a permit for a mansard roof. Different taxes will also be a concern. Some areas have height restrictions for mansard roofs and they need to be taken into consideration. Therefore, it is important to research local laws before deciding to invest in a mansard roof.

Variations of Mansard Roofs

Mansard roofs can include convex, concave or straight-angled designs. Windows add to the aesthetic appeal and offer more natural light inside the living space. A space in the mansard of a building can be used for a skylight. Some grand houses with mansard roofs also have wood quoins. Mansard roof designs are only limited to one’s imagination, they serve to be very versatile spaces.

Price of Mansard Roofs

Mansard roofing costs vary depending on the location, materials, labor and other factors. Since a mansard roof requires a lot of materials as well as framing labor, one can expect the roof to cost anywhere from $10 to $14 per square foot. For a 1,500 square foot roof space, this is roughly $15,000 to $ 20,000. Depending on the materials used, the total estimated costs can range anywhere from $20,000 to $50,000.