A pitched roof is a roof for which one or more roof surfaces is pitched more than 10 degrees,[1] and alternately a roof with two slopes that meet at a central ridge.[2] Some definitions are even more general, including any roof with a sloping surface or surfaces.[3]
The term roof pitch (in roof construction) refers to the angle of a roof from the horizontal. The word pitch can also be used as a verb, i.e old roof framers refer to having to "pitch a roof."
A variant of the pitched roof is the lean-to roof, a roof structure where the roof leans to one side of the house. Rafters are connected to the highest wall which are declined to a lower wall. The rafters are often connected into the wall individually or even supported on a wall plate bedded within the wall. This type of roof can have no joist at all or have a tie or have a joist with a strut to give more strength.