Shared Coordinates Process: Examine the Site/Survey File from Civil Designer
STEP 1: Typically, a site file (normally 2D, but can be in 3D) in dwg format from civil designer will contain the true real world coordinates for the project site. Surveyors and civil engineers use these global coordinate system in x, y, z.
STEP 2: Review the CAD file of the 2D site plan in AutoCAD and confirm units used and the coordinates are real world coordinates. Typically real world coordinate numbers are quite large. As an example:
In AutoCAD, this is shown on bottom left of the screen (x,y,z) with units in feet.
STEP 3: Identify the survey marker or station in the civil site file. If there is one, this will be reference point used to position the linked civil site file in Revit.
STEP 4: If there is no existing survey marker or station in civil site file, select a convenient reference point that will not be moved in reference to real world coordinates when there are updates to the construction drawings and confirm with the civil consultant that this reference is acceptable. Otherwise, request civil consultant to provide us a reference point to use.