A Gambrel or a barn roof, is much like mansard in a sense that it has two different slopes. The difference between the two is that the Gambrel only has two sides, while the mansard has four.
Similar to mansard, the lower side of the Gambrel roof has an almost vertical, steep slope, while the upper slope is much lower.
Gambrels are not only seen on top of barns, farm houses and log cabins. They are also seen on Dutch Colonial and Georgian style homes, as well.
Pros: Much like the mansard, the Gambrel provides extra living space for a garret, attic or loft. Plus it’s simple to frame out.
The Gambrel only uses two roof beams, along with gusset joints. Since the construction is quite simple with fewer materials needed, this helps to keep the cost of a roof down.
Gambrel roofs are also a great idea for outdoor sheds and storage buildings. Their shape can provide more storage without taking up more space.
Cons: The Gambrel roof is not recommended for heavy wind areas or regions that receive significant snowfall. The open design can cause the roof to collapse under extreme pressure.
Gambrel roofs also need to be constructed well, waterproofed at the ridges and maintained on a regular basis. It’s a good idea to have a Gambrel roof inspected each year to check for damage from storms, heavy rainfall or snow.
Windows are recommended to add light to the extra space. This is both a pro and a con. While all details will add to the overall beauty of a home, they increase chances for water leaks to occur.
Suggested Materials: The material used for a Gambrel roof will depend on the style of the house. Wooden, asphalt or slate shingles are widely used. However, using metal will greatly cut down on the amount of maintenance required.
Note: If a Gambrel roof is used in extreme weather areas, insist on reinforced trusses, especially on the upper pitch.
Listen instead of reading