For this Property, you cannot change the Data Types to one that uses model units (Length, Area, Volume, Angle). These Data Types are greyed out in the list.
This can occur in the following scenarios:
•you have assigned a custom Property value to one or more elements or materials that use this Property.
•In a Teamwork project, this Property was created by another user.
Reason: When you change a property’s Data Type, Archicad attempts to convert the existing property values. However, a Property value that has a model unit (e.g. a Length value) cannot be converted to a different unit (e.g. an Area value).
In this situation, switching Data Types is not allowed.
Similarly, you cannot edit the unit-based Data Type of a Property created by another user (in Teamwork).
Solution
•For item(s) with a custom value assigned for this Property, revert the Property value to its default
–Hint: Use Find & Select to locate such items: as the criterion, set “Property name”, with “custom value”
•Alternatively: In Property Manager, create a duplicate Property and set its Data Type as needed
•In Teamwork, you cannot change a Property’s data type if it was created by a different user.