Roof Types

Examples of different roof type configurations
Covering of the top of a building, serving to protect against rain, snow, sunlight, wind, and extremes of temperature. Roofs have been constructed in a wide variety of forms—flat, pitched, vaulted, domed, or in combinations.

The earliest roofs constructed by man were probably thatched roofs that were made of straw, leaves, branches, or reeds; they were usually set at a slope, or pitch, so that rainfall could drain off them. Conical thatched roofs are a good example of this type and are still widely used in the rural areas of Africa and elsewhere. Thicker branches and timbers eventually came to be used to span a roof, with clay or some other relatively impermeable substance pressed into the interstices between them. Gabled and flat roofs were possible with these materials. With the invention of brick and cut stone for building, the basic roof forms of the dome and vault appeared.

Two main types of roofs are flat roofs and sloping ones. The flat roof has historically been widely used anywhere where the climate is arid and the drainage of water off the roof is of secondary importance. Flat roofs came into widespread use in Europe and the Americas in the 19th century, when new waterproof roofing materials and the use of structural steel and concrete made them more practical. Flat roofs soon became the most commonly used type to cover warehouses, office buildings, and other commercial buildings, as well as many residential structures.

Sloping roofs come in many different varieties. The simplest is the lean-to, or shed , which has only one slope. A roof with two slopes that form an “A” or triangle is called a gable, or pitched, roof .

The shape and pitch of the roof can dramatticaly change the appearance of a building. The standard shapes are shown below.

Gable Roof A double sloping roof with a ridge and gables at each end. Gable roof is the simplest construction type of a roof and probably the most frequently used roof type all over the world. Gable roof consist of 2 roof surfaces, usually having the shape of a rectangle, they are of the same size and pitch. The line in which both roof surfaces meet is called a ridge or ridge line.
Hipped Roof A roof that slopes upward from all sides of a structure, having no vertical ends. The hip is the external angle at which adjacent sloping sides of a roof meet. The degree of such an angle is referred to as the hip bevel. The triangular sloping surface formed by hips that meet at a roof's ridge is called a hip end. A pyramidal hipped roof, also known as a pavilion roof, is hipped equally at all corners and the hips meet at a single peak, but the more common form of hip roof is above a rectangular structure, where a roof ridge meets two hips at either end
Barn Hip Roof a roof having sloping ends as well as sloping sides
Dormer Roof A roof with a large dormer window. This roof will normally have a gable end.
Gambrel Roof The gambrel roof is a type of gable roof with two slopes on each side, the upper being less steep than the lower. This popular roofing shape, often used for barns
Mansard Roof The mansard roof is a hipped gambrel roof, thus having two slopes on every side
Salt Box Roof A saltbox roof forms a lopsided triangle. Twentieth-century Split Level homes also can have a saltbox roofline, usually facing the front.
A-Frame Roof Introduced in 1957 by the architect Andrew Geller, an A-frame home is all roof with no perpendicular walls. These distinctive A-shaped homes are usually built as vacation cottages.
Flat Roof A roof having a very shallow pitch 1 to 2 degrees. The advantage of flat roof construction is that the building under can take any shape and the walls do not have to be parallel and perpendicular to each other.
Mono Pitch Roof or Lean too Roof The is the simplest roof form consisting of a single roof surface.