Modeling - Essential Skill

Learn how the changes you make to elements in one view are visible in all other views.

The Revit model is a virtual version of the building design. The model describes not only the geometry of the model elements, but also captures the design intent and logical relationships between the elements in the model. You can think of the 2D model views (plans, sections, elevations, and so on) as slices of the 3D model. Changes made to one view are instantly visible in all other views of the model, keeping the views in sync at all times. The 3D model is used to create the 2D views that make up the printed document set.

Terms and Concepts

Term/Concept Definition
Model Creates a 3D virtual representation of the design. The views of the project are slices of the model at a particular position. Every view of the model is a live view of the elements. If an element is moved in one view, then the position of that element in all of the views is instantly changed. The model also encodes design intent with constraints.
Constraint Establishes relationships between elements, so when an element is altered, the elements it is constrained to will also be changed to maintain the design intent of the model. For example, the tops of the walls may be constrained to the roof. When the roof is raised or lowered, or changes slope, the walls respond and stay connected to the roof element because of the constraint.
Sketch Defines the boundary of an element, such as a roof or a floor. In most cases, a sketch for an element must form a closed loop of lines for it to be valid. Sketch lines can be constrained to other elements to ensure that the boundary of the element will retain important relationships to other elements in the model.
View Shows the model from a specific viewpoint, such as a floor plan or section of the model. All views are live and changes to an element in one view will be instantly propagated to the other views of the model, keeping all views in sync. Views also establish where model elements are positioned when they are placed. For example, a roof plan view establishes the work plane for placing a roof, so that it is positioned at the correct height.

Video

This video demonstrates the following:
  • Place a roof element.
  • Move elements in the model.
  • Constrain a roof sketch to walls.

Transcript

This video demonstrates how the changes you make to elements in one view of a project model are instantly visible in all other views. These instant updates are possible because the model contains both the elements themselves, and the logic that manages the relationships between the elements.

To see this behavior in action, we will place a roof on the model. First select the roof plan view from the Project Browser. By selecting this view, you make the roof level the active work plane, which ensures that the roof you place will be constrained to the roof level in the project.

Next, set the overhang, and use the walls to sketch the boundary of the roof. After you have established the boundary, you can set the roof slope and finish the roof element.

Select the walls, and attach the tops of the walls to the roof. The walls are now constrained to the roof. When you change the roof geometry or position, the walls will respond to the change.

Similarly, because the walls were used to layout the roof sketch, the sketch lines of the roof are constrained to the walls. When you change the position of a wall using the temporary dimensions, the roof will respond to the change.

The model views are always in sync with each other. When an element is changed in one view, the change is instantly visible in the other views of the model. This ensures that your model is always up to date for viewing and generating printed documents.