Definition
In construction and architecture, elevation refers to the vertical height of a point relative to a reference level, typically sea level or a fixed benchmark. Elevation drawings show the vertical faces of a building (front, back, left, right sides) and are essential for understanding exterior appearance, dimensions, and grading. Site elevation determines drainage requirements, flood risk, and foundation depth.
Formula
Elevation is typically measured in feet above mean sea level (MSL) in the US. A 10-foot elevation change over 100 horizontal feet equals a 10% slope. For proper drainage, a minimum 2% slope (1/4 inch per foot) away from foundations is recommended.
Example
Elevation Calculation Example
A building site has a front elevation of 100 feet and rear elevation of 96 feet. The 4-foot drop over a 120-foot depth creates a 3.3% slope, which is adequate for drainage. Floor elevations are typically set 12-24 inches above the highest known ground elevation to prevent water intrusion.