What is the term for the line length of a rafter in roof framing?

The term "line length" refers specifically to the length of a rafter measured from the ridge (the highest point of the roof) down to the eaves (the lower edge of the roof). This measurement is crucial in roof framing because it determines how much material will be needed for the rafters and how they will be cut to fit accurately.

In roof framing jargon, while "rise," "run," and "span" all pertain to roof construction, they describe different aspects of the roof's geometry. The rise indicates the vertical height from the plate to the ridge, the run signifies the horizontal distance from the centerline of the ridge to the exterior wall, and the span is the total horizontal distance across the building from one wall to the other, encompassing both sides of the roof. The line length, however, is uniquely associated with the actual length of the rafter itself, making it the specific and correct term in this context.