IfcSite

IfcSite is an entity in the Industry Foundation Classes (IFC) schema that represents the geographic site context for a BIM project. It serves as the spatial container at the project level, anchoring geometry and other elements to a real-world location. The site often covers the project’s ground area, terrain, and surrounding environment and supports site-related analyses such as earthwork, drainage, and solar studies. It is typically named and may include descriptive or object type information.

Geolocation and placement are core aspects of IfcSite. The site uses a local placement within the project coordinate system and can carry geographic coordinates through attributes such as RefLatitude, RefLongitude, and RefElevation to enable georeferencing and GIS interoperability. A geographic context (IfcGeographicContext) may be referenced to define the coordinate reference system and datum used by the site, ensuring consistent alignment with real-world location data.

Structure and relationships: IfcSite acts as a top-level spatial element that groups project elements through the spatial structure hierarchy. It serves as the container for buildings, landscapes, and other components of the project and is linked to these elements via relationships such as those that place them within the site.

Usage and interoperability: In typical workflows, IfcSite provides the basis for location-based analyses, coordinate system alignment, and GIS data exchange. While optional in some IFC implementations, georeferencing the project through IfcSite is common practice for enabling accurate mapping, simulation, and coordination across disciplines.