AutoCAD Architecture, Don’t Look Back!

By Roger Liucci | CAD, IT

Autodesk released AutoCAD v1 in December 1982. that was DWG version number 1.0, it went incrementally for many years. The AutoCAD 2000 version file was in use for three years. In 2013 and 2018 AutoCAD Architecture shared a DWG version with the respective 2013 format and 2018 format.


AutoCAD 2013    DWG 2013 file format
AutoCAD 2014
AutoCAD 2015
AutoCAD 2016
AutoCAD 2017


AutoCAD 2018 DWG 2018 file format
AutoCAD 2019
AutoCAD 2020
AutoCAD 2021


Every 4th release historically has been a file format release and for the everyday AutoCAD user, this is no big deal. In plain vanilla AutoCAD, one can open ANY previous version and can save down to almost any previous version DWG.

For AutoCAD Architecture, or ACA, users who save their files in 2013 or 2018  and then save back to an earlier version to share with consultants or clients, those using a previous version of ACA can no longer edit the AEC objects as intelligent objects. The intelligent Doors walls and windows, for example, cannot be saved down to the previous version and maintain their intelligence. Upon opening the older DWG in AutoCAD Architecture they will get the following error.

Don’t save . . . or else










This means that the smart objects will be upgraded and not intelligent if downgraded to older DWG formats. Downgrading will make these objects dumb and not editable.

Users will not be able to change a simple door width for example. Also, we have seen users getting a ton of errors when opening a DWG that has been saved in a version of AutoCAD Architecture that writes a newer version DWG. for instance; “ARX error — e not of that class”

Options / Workarounds;

  1. Don’t look back. Save all DWGS in the current versions and ask your consultant to upgrade. 😉
  2. “Export to AutoCAD”  Command: _AECEXPORTTOAUTOCAD2010 Loading AEC Object Explode… This will explode all AEC objects to linework and blocks.

Hopefully, you find this article before you upgrade your entire ACA project to the newest release. If not hopefully your not using AEC objects. Hopefully, you will consider Revit.

Please comment or give me a call if I can be of assistance or if there are any other questions or concerns.


INDUSTRIES: Architecture, Buildings, Civil Engineering, MEP Engineering, Structural Engineering

Published on January 29, 2021 in .

About the Author

Roger, our senior BIM specialist, specializes in all things architecture & construction and has been with Microsol Resources since 2001. He provides technical support for our architectural, interiors, construction and engineering clients.