To fix warnings in Revit, open the Warnings dialog, group the warnings by type, and resolve the types that affect rooms, quantities and joins first. Hundreds of warnings usually come down to a handful of causes.
Find the warnings
- Open Manage › Inquiry › Warnings. Revit lists every warning in the model, grouped by message.
- Expand a group to see the elements involved. Check one and click Show to zoom to it.
- For a selected element, Show Related Warnings on the Modify tab lists only its warnings.
- Use Export to save the list as an HTML report and compare it over time.
Delete Checked deletes the elements you tick. For a pair such as identical instances, tick one copy, not both.
The most common warnings and how to fix them
- “Highlighted walls overlap”
- Two walls share the same line, so one may be ignored as a room boundary. Delete or shorten one. Where you only need a boundary, use a room separation line instead.
- “There are identical instances in the same place”
- A copied or pasted duplicate. Expand the warning, tick one of the two copies and use Delete Checked.
- “Room is not in a properly enclosed region”
- The room’s boundary has a gap. Close it with walls or room separation lines, or remove the room if it is left over.
- “Line is slightly off axis and may cause inaccuracies”
- A line drawn a fraction of a degree off true. Redraw or align it so dimensions and joins behave.
- “Elements have duplicate 'Mark' values”
- Often harmless, but it breaks tags and schedules that rely on Mark. Renumber where the value matters.
Work through them by type
Start with the warnings with the highest counts and those that change results: room boundaries, overlapping floors and walls, and duplicates that double quantities. Leave cosmetic ones for last. Fixing one cause, such as a copied group, often clears dozens of warnings at once.
If the model feels slow, start with duplicates and overlapping walls. Autodesk ties those to slower updates, and we measured what duplicates cost in Do warnings slow down Revit?