Overview
This lecture provides an overview of working with families in Revit 2025, including key concepts, tools, types of families, and basic family creation workflows.
Family Basics in Revit
- Families in Revit are components (2D or 3D elements) used to build a project.
- Families are created from templates with the extension .rft; final family files have extension .rfa.
- Common family templates used: window, profile, generic model, detail item, and door.
The Family Editor Interface
- The Family Editor opens with four standard views: left elevation, 3D, front, and reference level (plan).
- Main tools are found under the "Create" tab.
Reference Planes and Lines
- Reference planes are 2D elements extending indefinitely along two axes and are essential for family setup.
- Reference lines are 1D elements useful for controlling rotation and can define axes for geometry.
- Avoid rotating reference planes—use reference lines instead for rotation.
Drawing and Modeling Tools
- Symbolic lines: 2D, visible only in 2D views; model lines: 2D, visible in both 2D and 3D.
- Geometry is drawn on the "active plane," which can be set to any reference plane or geometry face.
Forms and Geometry Creation
- Extrusion: creates 3D geometry from a 2D profile extended along one axis.
- Blend: morphs between two 2D profiles on separate planes along one axis.
- Revolve: rotates a 2D profile around an axis to create 3D geometry.
- Sweep: extrudes a 2D profile along a path, which can move through any direction in space.
- Swept Blend: combines sweep and blend, transitioning between two profiles along a path.
Voids
- Voids are negative geometry that cut through solids, mirroring the creation tools for solids (extrusion, blend, etc.).
Constraints, Dimensions, and Parameters
- Dimensions measure between points and can be locked for constraints.
- Constraints restrict movement or changes to maintain design intent.
- Parameters (instance or type) control dimensions/constraints and allow user-driven variability.
- Parameters are created by labeling dimensions and managed in the "Family Types" dialog (four blue squares).
Types of Families
- 3D families: can contain 2D and 3D geometry.
- Annotation families (detail items): 2D only, use for drawings/annotations.
- Symbol families: 2D, can include text, but cannot contain reference planes.
- Nested families: placing a family inside another (parent/child relationship).
- Level-based (plane-based) families: placed on a reference plane in the project and can be set to different levels.
- Face-based families: placed on any solid face in the project.
- Adaptive families: allow placement by selecting multiple points that control family shape and placement.
Key Terms & Definitions
- Family — A reusable group of elements/components in Revit (2D or 3D).
- Reference Plane — A 2D infinite guide for geometry and alignment.
- Reference Line — A 1D guide, used for rotation and axis definition.
- Extrusion — 3D form created by projecting a profile along an axis.
- Blend — Form created by merging two profiles along an axis.
- Revolve — 3D geometry formed by rotating a profile around an axis.
- Sweep — Form made by moving a profile along a defined path.
- Swept Blend — Transitions between two profiles along a path.
- Void — 3D negative space that removes solid geometry.
- Constraint — A locked relationship between elements.
- Parameter — A variable that controls property values in families.
- Instance Parameter — Affects individual occurrences of a family.
- Type Parameter — Affects all instances of a family type.
- Parent/Child Family — Relationship when one family is nested inside another.
- Level-based Family — Placed on a reference level/plane.
- Face-based Family — Placed on any solid face.
- Adaptive Family — Placed and controlled by multiple user-selected points.
Action Items / Next Steps
- Practice creating basic families using generic model templates in Revit.
- Experiment with reference planes, lines, and drawing/modeling tools.
- Review the use of constraints and associate parameters with dimensions.
- Prepare for next class by exploring 2D families and annotation components.