Create a Reference Surface File
You can create a reference surface file by applying a positive or negative elevation offset to an existing design file. You can use this newly created reference surface file as a Design Boundary filter, and to complete cut/fill maps and Volumes calculations at an offset from a finished design.
To create a reference surface file, in the Import Panel, click the Actions menu next to the design name and select New Reference Surface.
In the pop-up, enter either a negative value (preceded by a minus sign) or a positive value. When you save it, a new reference surface file is created and given the selected design file name appended with the elevation offset value. This reference surface file now can be used anywhere a design file can be selected.
(Optional) Change the Name of your offset within the File Name.
Note: You can create multiple reference surface files from a design file as long as their offsets are unique negative or positive values. You can delete a reference surface file, but you cannot delete a design file if any reference surface file created from it still exists. You must first delete the reference surface files before deleting the design file.
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