One square is equal to 100 square feet. Examples where the unit is used are roofing shingles, metal roofing, vinyl siding, and fiber-cement siding products.

​The ridge of a sloped roof system is the horizontal top area where two sloped roof areas meet. The National Roofing Contractors Association defines ridge as “Highest point on a roof, represented by a horizontal line where two roof areas intersect, running the length of the area.”

​​A gable is the generally triangular portion of a wall between the edges of intersecting roof pitches.

A depression or hollow resembling or suggesting a valley, as the point at which the two slopes of a roof meet.

​Flashing is usually aluminum or galvanized steel that’s used over joints in roof and wall construction to prevent water seeping in and causing damage.

​A hip roof, hip–roof or hipped roof, is a type of roof where all sides slope downwards to the walls, usually with a fairly gentle slope (although a tented roof by definition is a hipped roof with steeply pitched slopes rising to a peak).