Why are lines missing when switching from Floor Plan to Ceiling Plan View?

Issue description

When switching from Floor Plan View to Ceiling Plan View, certain lines that were visible in the floor plan disappear completely. The missing lines appear to be associated with elements that have their line category set to Skin separator line. You can confirm this by checking the line properties in the Line Settings dialog box.

Solution

This issue occurs because ceiling plan views typically use a Graphic Override combination that has the Hide Skin Separators setting enabled by default. When lines are categorized as Skin separator lines, they become subject to this Graphic Override setting and will be hidden when the setting is active.

1. Select the missing lines in your floor plan view where they are still visible.
2. Right-click and choose Line Settings from the context menu.
3. Navigate to the Properties Panel in the Line Settings dialog box.
4. Change the Line Category from Skin Separator Line to either:
   • Cut line for structural or building element contours
   • Drafting line for general 2D annotation lines
     
5. Click OK to apply the changes.