Another nice workaround by Philip Chan – if you want to change one of Revit’s built-in Type Parameters (derived from a Family Template, such as Door Fire Rating) to an Instance Parameter, you just have to take the Family on a little round trip to a more flexible Family Category.
- New Door based on Door Family Template
- Switch to Generic Model Type
- Change built-in Type Parameter for Fire Rating to Instance
- Switch back to Door Category
You can read Philip’s whole post at:
Phil-osophy in BIM: Hacking System Parameters in Door Family