Roofs can be categorized into two categories depending on their general shape, flat roof or sloping roof. Flat roofs are more common in commercial buildings while sloping roofs are more common in residential properties. Sloping roofs can have a variety of shapes and styles depending on the home’s needs and aesthetics.
Pitch of a Roof
The pitch or slope of a roof is mathematically understood as the rise over the run and written as 4/12, 4:12, 4 in 12, or 4 over 12 where 4 is the rise and 12 is the run. The normal pitch of a roof is somewhere between 4/12 and 9/12, anything under 4 is considered a low slope while anything over 9 is steep. Any pitch roof lower than 2/12 is a flat roof.
So what pitch should you choose for your roof? Your architecture will be the best resource in determining the pitch of your roof. They will factor in many details including materials used in building the house. They will also consider the climate you live in. A roof that is too flat in colder climates will not allow snow to slide off of it, possibly causing the roof to collapse due to the weight of a snow. If a roof’s slope is too steep though, it can cause a hazard of snow falling off the sides too quickly and on top of people below. An experienced architect will be able to determine what pitch is right for the design of the house as well as its functionality.
Types of Sloping Roofs
Believe it or not there are many different types of sloping roofs, each having their own pros and cons. We will go over the most popular types here.
The most popular slopping roof is the gable roof, which has two rectangles of the same size that join at the edge creating the slope. The result is a pleasing and balanced roof that can be found in many different kinds of materials. The biggest pro of the gable roof is it is a simple design making it easy to construct and less expensive. The steepness of their slope allows for water and snow to be easily shed and the space created for an attic or vaulted ceilings within the home. The alternative of the steep pitch is it is more liable to wind and not ideal to ares of the country that experience tornadoes.
Salt Box Roof
The salt box roof does not differ much from the gable roof except for that one of the roof panels is longer than the other resulting in a steeper pitch with a more distinct look. This style of sloped roof was most popular in the Colonial era and not seen today as much in newly constructed homes. You will see it most option on garages, sheds, or outbuildings. A pro of the salt box roof is the distinguished look it gives to a home in both modern and rustic environments. Since the slope is near the end of the home, the roof’s pitch needs to meet the walls that frame the rear which will also give you an interior ceiling that slopes. Consider the slope of that interior ceiling when planning your home because it will hinder you from storage areas like attics.
The Dutch origin of the gambrel roof allows for two different slope pitches on the same house. While it has two twin roof panels like the gable roof, they are not straight creating an upper slope angle that is wide and a lower, steeper slope angle. The effect is that the second levels of the home are spacier while still having the appearance of a sloped roof. The gambrel roof is most often seen larger homes, are easy to frame, and boast excellent drainage. The biggest con to the gambrel roof is its frequent demand for maintenance.
Similar to the gambrel roof is the mansard roof, but with four sloping sides resulting in a slope on all sides. The steepest angle being present at the lower slope and the wider angle on the upper. Mansard roof designs automatically leave room in your home for attics that can be converted into extra bedrooms or loft areas easily. These sloping roofs are more complex to build thus costing more in labor and materials.
Another four sloping sided roof, is the pyramid roof. As its name suggests it forms a pyramid shape. A pyramid roof is best for smaller structures and are more and more popular in contemporary architecture. A big pro of the pyramid roof is it results in a more energy efficient home because the roof overhangs on all sides providing shade in the warmer weather months. The pyramid roof is the more expensive sloped roofing type since its shape results in more surface area than others but less space for attics and storage.
Sloping roof types can have many different factors and options to choose from. Be sure to consult your architect or EMA Construction’s qualified roofers when deciding which type will fit your home best.