> For the complete documentation index, see [llms.txt](https://technical.geometrygym.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://technical.geometrygym.com/rhino-grasshopper/revit/working-with-ggrvt/families.md).

# Families

## Creating Families in Grasshopper

## Reference Existing Families

Using the geometry gym plug-in you can reference existing families within an open Revit model. For example your company may have its own defined Revit framing family with predefined parameters which you would like to use.

Using a representative family definition within Grasshopper (i.e. profile shape) and use a naming convention with a ‘:’ delimiter (i.e .MyFamily:MyType) for the type name you can easily perform this reference to the existing Revit type.

{% hint style="warning" %}
Note that if the family is not loaded it will create the family.
{% endhint %}

The import process will break down the name and search on that basis. The Revit plugin always search’s for an existing material or type and uses it first and foremost unless the option nominates to override.

The image below shows how you can reference an existing family type of a Circular Hollow Section family.

![](/files/PmcdVMREdHEYVM2Gs44L)