What is the term used for the base of the triangle in roof framing?

The term "run" refers specifically to the horizontal distance from the ridge of the roof to the wall plate, which effectively serves as the base of the triangle in roof framing. In roof framing, triangles are often used to describe the slope and pitch of a roof, where the run is an integral component.

The "pitch" of a roof generally represents the ratio of the vertical rise to the horizontal run, thus providing a measure of steepness but not serving as the base itself. "Slope" describes the angle of the roof but again does not refer to the specific horizontal distance that forms the triangle’s base. Lastly, "eaves" pertain to the lower edge of the roof that overhangs the walls, which is unrelated to the geometric aspect of a triangle formed in roof framing. Thus, "run" is the correct term to identify the base of the triangle in roof framing.