Select a placed instance and click Edit Family, or right-click the family in the Project Browser and choose Edit. Make the change, then click Load into Project and choose whether to overwrite the existing version.
Or, just ask Mira, a free add-in, to make a size change and say if it needs the Family Editor.
How to do it in Revit
Step 1: Decide if you need the Family Editor
Many changes don't. Sizes and other type parameters change in the project: select an instance, click Edit Type in the Properties palette and edit the value in Type Properties. Open the Family Editor to change geometry, add parameters, or change what every project that loads the file gets.
Step 2: Open the family
Select a placed instance and click Modify | <Category> tab › Mode panel › Edit Family, or right-click the family in the Project Browser and choose Edit. The project stays open behind it (Autodesk Help: Modify Families in a Project). To open the file itself, use File tab › Open › Family.
Step 3: Make the change
Click Create tab › Properties panel › Family Types to change values, add types or set formulas, and click Apply to watch the geometry follow. The family's category is under Family Category and Parameters on the same panel (Autodesk Help: Family Types Dialog).
Step 4: Load it back into the project
Click Load into Project, or Load into Project and Close, on the Family Editor panel. With more than one project open, choose which ones get it. To reload a changed .rfa from the project instead, see how to load a family.
Step 5: Choose how to overwrite
If Revit says the family already exists, pick Overwrite the existing version to keep the parameter values set in the project, or Overwrite the existing version and its parameter values to take the values from the family.
Step 6: Save the .rfa if the change should last
A family edited from a project changes only that project's copy. To keep the change, click File tab › Save in the Family Editor and save over the original .rfa or under a new name. You can also right-click the family in the Project Browser and choose Save.
What to watch for
System families don't open. Walls, floors, roofs and ceilings are system families. You change them by editing or duplicating their types in the project, not in the Family Editor.
In-place families edit differently. An in-place family is modeled inside the project. Select it and click Modify | <Category> tab › Model panel › Edit In-Place instead.
Nested families reload in order. Edit a nested family from inside its host, load it into the host, then load the host into the project.
A renamed type comes in twice. Reloading never removes types, so a type you rename in the Family Editor arrives as a new type beside the old one. Change the old instances over, then purge it.
The type name doesn't follow the size. Change a desk's width from 48 to 60 inches and the type is still called 48". Rename it in the same edit, or the schedule will say one size and the drawing another. To add a size instead, see how to add and change family types. To make one value follow another, such as a rough opening that follows the door's width, see how to use formulas in family parameters.
One edit, many copies. A family edited in one project drifts from the firm's original .rfa, and the next project loads the old version again. Over a few years the same door exists in a dozen versions. Revit family management keeps the approved version marked, so a fix made on one job reaches the next. Building one from scratch is covered in how to create a family.
Or, just ask Mira to do it.
Mira is an AI thinking partner for Revit that automates the work you repeat and builds tools your team needs.
- Type this in Mira
Open this desk's family, set its Width to 5'-0", and load it back into the project.
Mira checks whether the change needs the Family Editor at all. In our test, Width was a type parameter, so Mira changed it in the project, said so, and flagged that the type name no longer matched the size.
How do I open the Family Editor in Revit?
How do I edit a family in Revit without the Family Editor?
Why can't I edit a family in Revit?
How do I save a family from a Revit project?
What does Overwrite the existing version and its parameter values mean?
Related Revit how-tos
- How to Create a Family in RevitClick File tab › New › Family, pick a template such as Generic Model, and set Family Category and Parameters. Draw reference planes, label their dimensions as parameters, lock geometry to them, add sizes in Family Types, then save and Load into Project. Or, just describe a simple family and Mira builds it and places it in your model.
- How to Create and Change Wall Types in RevitSelect a wall, click Edit Type, then Duplicate, and name the new type. Click Edit next to Structure to set each layer's function, material and thickness. To change walls to the new type, select them and pick it in the Type Selector. Or, just ask Mira, a free add-in, to swap every wall of one type to another on a level.
- How to Load a Family in RevitClick Insert tab › Load from Library panel › Load Family, browse to the .rfa file and click Open. Select several files to load them together. To update a family that's already in the project, right-click it in the Project Browser and choose Reload. Or, just ask Mira, a free add-in, to load the families in a folder you pick.
- How to Create a Corner Mullion in RevitDelete the two mullions where the curtain walls meet, click Architecture tab › Build panel › Mullion and pick an L, V, Trapezoid or Quad corner type. Click the corner grid line to place it. For your own size, duplicate a type. Or, just ask Mira, a free add-in, to list the curtain wall corners still missing one.
- How to Use Formulas in Revit Family ParametersIn the Family Editor, click Create tab › Properties panel › Family Types. In the Formula column next to a parameter, type an expression with exact parameter names, such as Width + 2". Click Apply to check. Formulas take arithmetic, if(), rounding and trig. Or, just ask Mira, a free add-in, to set formulas on parameters the family already has.
- How to Create and Use Type Catalogs in RevitA type catalog is a .txt file with the same name and folder as the family's .rfa. Its first row declares parameters as Name##type##units; each row after it is a type. On load, Revit lists the types so you pick only the ones you need. Or, just ask Mira, a free add-in, to add a type to a catalog.
Try it yourself.
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