Understanding The Roofing System
There are actually two major types of roofs with multiple variations derived from these two roof types (except of course flat roofs). These two roof types are Gable Roof and Hip Roof. Depending on the roof type, you will need to order a different amount of roofing materials, when you are going to replace your roof. It is equally important for homeowners and roofing contractors alike to know this, as it will affect your roof cost.
Depending on the type of roof you have, the roof price will differ, as will the difficulty of installing the roof, and the amount of waste associated with each type of roofing materials. You can refer to our roofing materials calculator to see exactly how much and which roofing materials you will need to order for your roof, depending on whether it is a gable or hip roof variation.
Gable roof is the most common and the simplest type of roof – it is a two-sloped roof, like an open book, turned up side down. The name “gable” comes from a roof detail, also called rake, the sloped edge of the roof, which you see when standing on the side of a house.
Gable roofs are the easiest to install, especially when they have a rather shallow roof pitch of 3-7, and will have the lowest amount of waste roofing materials. It only gets complicated when you get additional roof structures on the gable roof, such as dormers / shed dormers, valleys, etc. Then the amount of flashing and other roof detail work increases.
Hip roofs are the second roof type, which resembles a pyramid. Hip roofs have four roof planes, which connect on the corners of each side of the roof. A typical hip roof will have two triangle roof sections on shorter sides and trapezoid roof sections on longer sides of the roof. A square hip roof will have 4 triangular sides, and will represent a perfect pyramid.
It is important to note, that when you measure a hip and a gable roof, assuming that ground dimensions and roof pitch are the same, both roofs will have the exact same geometrical size, though common sense may lead you into thinking that a hip roof area will be larger. At the same time, the amount of roofing materials needed for a hip roof and roof installation cost for a hip roof will be an average 15% higher than the same size gable roof.
A mansard roof is essentially a hip roof with high roof pitch (usually 18 over 12 pitch or more), with the top of it “cut off and replaced with a flat roof. Typically you will see a flat / mansard roof combination on older multi-story buildings in urban settings. There, a mansard roof is used mostly for decorative purposes. However, it is still a roof, and protects the building from rain / snow and other elements and therefore, it must be treated appropriately.
Mansard roof installation costs are typically higher than other types of roofs, as there is a lot of detail involved, such as multiple window openings and other decorative details common in 19th and early-to-mid 20th century construction methods.