A gambrel roof is a two-sided roof with two slopes on each side. This roof design is often referred to as a “Dutch roof” and is a popular design style for barns and sheds.
In this article, we’ll go over the basics of gambrel roofs, including their pros and cons, how much they cost to install, and the common types of gambrel styles. If you need a repair or replacement for your gambrel roof, enter your ZIP code to be connected to a roofer in your area.
What is a gambrel roof?
Gambrel roofs are unique in design, as they are two-sided roofs with symmetrical slopes on each side. The lower slope, which is almost vertical, is steeper than the upper slope. The upper slope is typically constructed at a 30-degree angle, while the lower slope is approximately 60 degrees.
Gambrel roofs are designed to maximize interior space. This is the primary reason they are used for barns, sheds, or storage buildings. The steep angle of the lower roof slope allows for more headroom under the roof line. This transforms the upper level from a limited-sized attic space to a functional, usable area.
You can enhance the appearance of a gambrel roof by installing double-hung windows that provide natural light or add dormers to increase storage space.
Common types of gambrel roofs
Gambrel roofs provide both form and function. Their classic, traditional look makes them aesthetically pleasing and architecturally unique. Unlike conventional steep slope roof styles with two sections sloping in opposite directions, gambrel roofs can have multiple roof lines, dormer curves, and ornamentations.
Gambrel roofs can be customized from the classic style of two slopes per side to meet any homeowner’s request or designer’s imagination. This versatility has led to the popularization of many types of gambrel roofs. The most common gambrel roof styles include:
Classic: A classic gambrel roof is the most common style, typically seen on sheds, barns, and other storage structures.
Mansard: This style of gambrel roof is nearly identical, but there are four sloped sides instead of two. The lower slopes are steeper than the upper slope areas on both styles of mansard roofs.
Valley: Typically seen on square-shaped houses, this style has two front-facing slopes in addition to the two sloped sides.
Dormer: You may see gambrel roofs with windows protruding out the sides. These window chambers, called dormers, provide more interior light and add depth to the exterior appearance of the roof.
Pros and cons of gambrel roofs
Pros
- + Cost-effective
- + Versatile roof style
- + Classic, traditional appearance
- + Easy to build
- + Provide excellent drainage
- + Extra interior space
- + Long service life
Cons
- - Poorer protection against extreme weather
- - Require regular maintenance
- - Roof covering experiences uneven wear
- - Susceptible to poor ventilation
When deciding between a gambrel roof and other roof styles, it is best to analyze the pros and cons of your specific wants and needs.
Gambrel roofs are most commonly installed on barns, sheds, and storage buildings because they provide additional usable space on the top level. The additional usable space can also benefit a homeowner who wants a functional attic.
Another advantage to homeowners is the gambrel roof’s distinct appearance, which can separate their home from the “cookie-cutter” look in a neighborhood. Gambrel roofs are also typically easy to build, can provide excellent drainage, are long-lasting, and are cost-effective to build.
There are drawbacks to these types of roofs as well. Gambrels require regular, annual roof maintenance that is unnecessary with other steep-slope roofs. The difference in slope of the roof sections leaves some areas more exposed to some aspects than others. For example, the low-sloped top sections may be prone to damage from snow loads, ultraviolet exposure, and extreme weather conditions, while the steeper sections are more vulnerable to damage from high-velocity winds.
Ventilation can also be a concern, particularly if the roof lacks insulation. Installing a ventilation fan or using other ventilation methods can correct these issues.
How much does a gambrel roof cost to install?
On average, installing a gambrel roof costs between $15,159 and $27,580. In some cases, a roof installation could cost as little as $7,271 or as much as $79,931.
The cost depends on several factors, including framing materials, labor, shingle type, and roof size. To find a local contractor to provide an accurate estimate, enter your ZIP below.
Gambrel roof vs. gable roof
Gambrel roofs and gable roofs are commonly confused, but there is a distinct difference between these similarly named roof types.
Gable roofs are the most common type of steep-slope roof and are considered conventional roofs, as they have the classic roof shape of two sections sloping in opposite directions. The gambrel roof is a two-sided roof with two slopes on each side.
Examples of gambrel roofs
As mentioned, gambrel roofs are most commonly used for barns, sheds, and storage buildings. Due to their unique design style and multiple roof lines, they are also common on contemporary, Georgian-style, and Dutch colonial-style homes. Here are a few real-world examples of gambrel roofs:
Cottage with a gambrel roof
Gambrel roof designs have been used on cottages in North America since the 16th century.
Gambrel roof on a detached garage
Image source: The Project Plan Shop
Gambrel roofs are installed on garages that utilize the top floor for additional storage.
Large barn with a gambrel roof
Gambrel roofs are typically installed on barns because they provide additional interior space on the top floor for storage.
Shed with a gambrel roof
Gambrel roofs are typically installed on sheds because they provide additional interior space for storage, stacking items, shelves, and headroom.
Gambrel roof on a modern home
Gambrel roofs have a classic, traditional look that makes them aesthetically pleasing and architecturally unique. Unlike conventional steep slope roof styles with two sections sloping in opposite directions, gambrel roofs can have multiple roof lines, dormer curves, and ornamentations.
John A. D’Annunzio has over 35 years of experience in roofing, building exteriors, and waterproofing consulting and has completed projects throughout the world. He has written five books about roofing/waterproofing and over 100 articles published in construction trade magazines. He has also conducted extensive research in material technology, the results of which have been reported at numerous national and global symposiums and conferences. Mr. D’Annunzio frequently conducts seminars and webinars related to building exterior technology.
Frequently asked questions
Gambrel roofs have been installed on commercial and residential buildings for centuries. Today, they are most commonly used on barns, sheds, and storage buildings because they provide more top-story interior space than the other roof types. They are also popular on contemporary, Georgian, and Dutch colonial homes because of design flexibility, additional space, and cost savings.
A mansard roof is a type of gambrel roof. This style of gambrel roof is nearly identical, but there are four sloped sides instead of two.
Gambrel roofs on residential structures are typically constructed with wood. Commercial buildings may use steel or other materials. Other materials used on residential gambrel structures include wood (two-by-fours) for rafters, plywood or OSB board, and assorted nails (6d nails, 16d nails, and 8d nails).
If properly constructed and maintained, gambrel roofs will last decades. The structural components should last the lifetime of the structure. Like on all roofs, gambrel roof covering materials will degrade over time due to exposure and normal wear.