The base plane serves as a fundamental element in lower-density and contextual districts, as well as in areas subject to waterfront zoning regulations. It sets the starting point for calculating a building's height. In most cases, the base plane is established at curb level, representing the height at which a building meets the street.
The base plane is not always a fixed point; it can vary depending on the specific conditions of a site.
One of the key functions of the base plane is to adapt to different terrain and site conditions. For example, on sites with slopes where the ground gradually rises or falls away from the street, the base plane is adjusted to account for this variation. This ensures that the building's height is calculated relative to the natural ground level. (nyc.gov, 2023)
The base plane is important on large lots where buildings may be set back significantly from the street. In such cases, using the curb level as the base plane would be impractical. Instead the base plane is adjusted to reflect the level at which the building makes contact with the ground. This adjustment prevents excessively tall structures in areas with lower-density zoning regulations.
Waterfront zoning is another crucial context in which the base plane is used. In such areas, the base plane is established at the mean high-water line, providing a reference point that considers the proximity to the water's edge. This ensures that developments near water bodies maintain a way of preservation of the natural environment.
