What is defined as the internal angle formed by two sloping sides of a roof?

The internal angle formed by two sloping sides of a roof is referred to as a valley. In roofing terminology, a valley is created where two planes of the roof intersect, allowing for water runoff to flow down into the gutter system, minimizing the risk of leaks and pooling water. This angle is significant as it dictates how effectively water is directed and can affect the roof's overall drainage and longevity.

In contrast, a ridge is the horizontal line at the top of the roof where two sloping sides meet, while an eave refers to the edge of the roof that overhangs the exterior walls. A hip is a type of roof design that has slopes on all four sides but does not specifically refer to the angle formed between the sloping sides. Understanding these definitions is essential for proper roofing terminology and can greatly impact the decision-making process during construction or repairs.