1. Open archiSum
Design > Architools > archiSum. The main palette shows grouping criteria, zone filters, area settings, and the target property in one panel.
2. Choose the grouping property
Pick the property archiSum should group by: typically an Apartment Number, Zone ID, or a custom property you already use on zones.
3. Filter zones
Restrict which zones get counted by layer (e.g. only 'Living Areas') or zone category (e.g. exclude 'Circulation'). Add a property-based filter for finer control.
4. Pick area mode
Choose Measured Area or Calculated Area depending on whether you want raw polygon area or the reduced area Archicad computes for low-ceiling or sloped parts.
5. Choose the target property
Select the zone property where the total should be written: e.g. 'Apartment Total Area'. Every zone in the group will have the same total written to it.
6. Preview and apply
Click Preview to highlight affected zones in the viewport, then open the Summary dialog to review apartment groups, areas, and excluded zones. Click Apply when you are happy. Use Undo any time to revert.