By Dennis Collin
When working with Revit families, it is essential to be familiar with the different types of parameters that exist within Revit. Within component families for example, there are 3 types: Built-in parameters that are hard coded within the program and can be used to adjust geometry and be tagged and scheduled once loaded into a project. User definable parameters include Family Parameters which tend to be used just for graphical alterations. These parameters cannot be scheduled or tagged when loaded into a project. If this functionality is required, then Shared Parameters must be used. Shared parameters can do everything a family parameter can, however, it will require the setting up of a Shared Parameters File which will typically be set up on a network server, or more recently can be located with Autodesk’s new Shared Parameter cloud service.
I have written about the different parameters in more detail elsewhere on Cadline Community , the links to which are located at the bottom of this post.
Built-in parameters, as previously mentioned are hard coded into Revit and at first glance it appears that the parameters cannot be edited. Taking a door component family as an example, a door has a few parameters, including height and width. However, accessing the parameters via the Family types interface reveals the parameter properties which are all greyed out and it seems that settings cannot be changed.
A common requirement with families is to be able to change parameters between Instance (unique/bespoke) to Type (per style/type). Whilst this is easy to do when creating family and shared parameters, it may not seem so obvious when working with Revit’s Built-in parameter types.
However, there is a way! Typically, this change is required if the door or window family needs to be at many sizes as in the case of measured building surveys of existing buildings.
The answer is to select the dimension that the length based built-in parameter is assigned to. This dimension can be usually found within the plan view of the component family file.
Select the dimension label and toggle the Instance/Type switch on the ribbon menu. The default setting for most parameters on the supplied templates is Type but can easily be set to instance if required.
For more information on Revit’s different parameter types links below:
Revit Parameters