if i understand correctly, you're asking about how to get rid of the grey areas to each side of the building.
those can be turned on or off by the Elevation Range within the Section or Elevation marker.
simply right-click in open space & click Elevation Range. that will remove/display the grey areas on the sides.
AC25 | Win10 | 64 bit | 16Gb RAM |Intel i7 8700 @ 3.20Ghz
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