Ensure you are running ArchiCAD 27 (Build 3000 or higher). Download the specific Eptar 2024 for AC27 installer. Unlike older versions, AC27 requires the add-on to be signed. Verify the "Add-On Manager" shows Eptar as "Loaded."
ArchiCAD 27 improved its handling of IFC structural attributes. Eptar uses this to automatically differentiate between standard hook lengths, seismic crossties, and lap splices. You can now define a "Seismic Zone 4" preset, and Eptar will apply the ACI 318-19 or Eurocode 2 rules automatically to every beam and column. eptar reinforcement for archicad 27