Ridges are tiles that are used on the ridge of the roof, when the rest of the roof is covered with roof tiles. They are often slightly larger and heavier than other roof tiles because there is occasionally stronger wind at the ridge and there are no other roof tiles on top to stop them from being blown off. The often almost semi-circular shape is also different from the other roof tiles. Again because they are at the top and the rainwater must be able to drain both left and right to the roof surfaces. That is also a reason that the ridges actually can only be found on gable roofs, pyramid roofs, hipped roofs, mansard roofs and jerkenheads. Ridges, for example, are rare on clerestory roofs, Skillion roofs and butterfly roofs. Ridges are available in ceramic and concrete variants and in many color variations, so that there is almost always a matching ridge variant for the type of roof tile that is used.