"...click on Graded Surface... If you don't do this first step, you will not get Cut and Fill counts when you create Building Pads."
"Be sure that first you select the Topography, then click on the Building Pad Button on the Massing & Site Tab. Otherwise, the Pad will be created, but sometimes (I haven't figured out why and how this happens) the Cut and Fill will not be reported on the Topography Schedule."
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CAD addict: Revit: Using Building Pads Properly - Part II