DesignBuilder dsb file version compatibility

DesignBuilder has always supported "backward compatibility", i.e. newer versions of the software can successfully read in files last saved in older versions.

Since v7.2, it also supports "forward compatibility" through the DesignBuilder XML file format. This enables older versions of the software to read files last saved in more recent versions. This is especially important when users must use a specific version of the software for certification (e.g. SBEM). 

In general, models should be created in the same version of the software that will run calculations, however if you used a more recent version of the software to create the model, and then need to load it into an older version you should export the model in DesignBuilder XML format and import the XML file into the required target version.

Compatibility between older versions
If you have opened a v6 file in DesignBuilder v7 then you can find a copy of the original v6 model saved in the Upgrade folder: C:\Users\<your_username>\Documents\DesignBuilder Data\Upgrade 

The archived filename will have the word Archive and the session timestamp.
It should be something like:
Test 20x20-12C (1) Archive 01-07-2021_11_06_38.dsb

For models created in version 7.1 and earlier, there is an option to export the gbXML file (currently only geometry, constructions and glazing is exported) and import it back to DBv6 using the import 3D BIM option and then set up the input data again. Components and templates can be exported and imported through DDF files.

See also Convert model geometry from DesignBuilder v7 to DesignBuilder v6