You may have loaded a family into your Revit model, let’s say a piece of furniture, and you go to cut your section just like usual. But when you look at that section, you notice that you are looking at that furniture family in elevation, even though you are cutting right through it! Revit does a great job of cutting through walls and floors and casework and ducts and more, but some categories you can never seem to see a cut view of. It turns out, this is completely by design. Revit has divided its categories into “cuttable” and “non-cuttable”. The cuttable categories are:
Source: Revit Tip: My Family Won’t Cut in Section Views | CADD Microsystems
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