In roofing, what is referred to as "run"?

In roofing terminology, "run" refers specifically to the horizontal distance from the ridge (the highest point of the roof) down to a vertical line directly beneath it, typically at the eave. This measurement is crucial for determining the overall slope and design of the roof, as it helps in calculating both the pitch and the area that needs to be covered with roofing materials.

Understanding "run" is essential in various roofing practices, from installation to estimating materials. It ensures that the roof has proper drainage and structural integrity. By accurately measuring the horizontal distance, roofers can make informed decisions about the slope and angle necessary for water runoff and can thus effectively prevent potential issues like leaks or pooling water.

The vertical height measures a different aspect of the roof known as "rise." The length of roofing material does not directly correlate to the geometry of the roof itself, and "slope" describes the ratio of rise to run, which is a separate concept.