Both breps are closed solids.
I’ve tried Add Form in a family document, but the result is the same.
SIDE BLDG.gh (241.5 KB)
There are some bad edges on your geometry.
how was that object made? I was able to DupBorder on the top surface, create a PlanarSrf and Gumball extrude it and it worked fine.
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SITE BLDG RE.gh (460.1 KB)
Basically, mesh in > get base crv > extrude in GH > cap > clean the bad ones > closed brep out > RIR
I know… its definitely more efficient to just import the whole rhino file into revit.
It’s part of the 3d model transfer/remake testing.