There are quite a few renumbering add-ins available for Revit. This free little package from CTC includes a tool to renumber both Rooms and Doors…
Sequence numbering on doors numbers doors independently. The tool remembers the previous door’s number and will maintain the proper sequence on subsequent doors.
Revit Renumbering Video Tutorial – 2:00
Revit Renumbering Product Information
Revit Renumbering available on Autodesk Exchange:
You can also get Imaginit Room Renumber on Exchange at:
Autodesk Exchange Apps