What is the term that describes the incline of a roof as a ratio of vertical rise to horizontal run?

The term that describes the incline of a roof as a ratio of vertical rise to horizontal run is pitch. Pitch is a specific representation of the steepness or angle of a roof, often expressed as a fraction or ratio indicating how much the roof rises vertically for a given horizontal distance.

In the context of roofing, pitch is essential for determining water drainage, structural integrity, and suitability for various types of roofing materials. A higher pitch indicates a steeper roof, which can significantly affect the overall design and functionality of the structure. Although slope and grade can pertain to inclines in different contexts, pitch is specifically focused on roofing and is the standard terminology used in the industry to discuss roof design.

While altitude refers to the height of an object in relation to sea level and is not related to roof geometry, the distinction between pitch and slope is subtle. Both terms represent incline, but pitch specifically pertains to roofing configurations, while slope may refer more broadly to inclines in various settings.