To select a boundary line in Revit, the most common and efficient method is to utilize the Pick Lines tool, which is an integral part of various sketch-based creation commands.
Understanding Boundary Lines in Revit
In Revit, a boundary line is a fundamental element that defines the perimeter or edge of various building components. These lines are crucial for sketching the shape of elements like:
- Floors, Roofs, and Ceilings: Defining their outer edges.
- Openings: Creating cutouts within elements.
- Walls and Railings: Placing them precisely along existing geometries.
- Rooms and Areas: Establishing their analytical perimeters.
- Property Lines: Representing land boundaries.
The Primary Method: Using the Pick Lines Tool
The Pick Lines tool allows you to quickly select existing model lines, edges of elements, or other reference lines within your Revit model to define a new sketch boundary without manually redrawing them. This saves time and ensures accuracy by aligning new elements with existing geometry.
What is the Pick Lines Tool?
The Pick Lines tool is a powerful feature found in the "Draw" panel of the ribbon whenever you are in a sketch-editing mode (e.g., when creating a floor, roof, or editing a profile). It enables you to instantly convert existing lines or edges into the boundary lines for the element you are creating.
Step-by-Step Guide to Using Pick Lines
Follow these steps to effectively select a boundary line using the Pick Lines tool:
- Initiate a Sketch-Based Command: Start the command for the element you wish to create or modify. For example:
- Go to the Architecture tab and click Floor, Roof, or Ceiling.
- Select an existing element and click Edit Boundary or Edit Profile.
- Go to the Architecture tab and click Wall (then choose a placement method).
- Access the Draw Panel: Once in sketch mode, a contextual tab will appear (e.g., Modify | Create Floor Boundary or Modify | Place Wall). Locate the Draw panel within this tab.
- Select the Pick Lines Tool: Click the Pick Lines icon, often represented by a line with a small cursor pointing to it.
- Tip: You can also type "PL" as a keyboard shortcut if you are in a sketch-editing mode.
- Adjust Offset (Optional): In the Options Bar, you can specify an Offset value. This will create your new boundary line at a set distance from the line you pick, which is useful for creating elements with a specific overhang or inset.
- Hover and Select: Move your cursor over the desired existing line, edge, or face in your model. Revit will display a blue preview of the line segment that will be selected.
- If you hover over a chain of connected lines, you can often pick them all by ensuring "Chain" is checked in the Options Bar, or by hovering close to the end of a segment.
- Click to Confirm: Click the left mouse button to select the line. Revit will convert it into a boundary line for your current sketch.
- Complete the Sketch: Continue picking lines until your sketch is fully defined and forms a closed loop (if required for the element type).
- Finish Edit Mode: Once your boundary sketch is complete, click the Finish Edit Mode (green checkmark) button in the ribbon to create the element.
Practical Example: Placing a Wall on a Toposurface Edge
A common scenario where Pick Lines proves invaluable is when you need to precisely place a wall along an existing boundary, such as the edge of a toposurface.
For instance, when creating a wall, you can navigate to the Architecture tab, select the Wall tool, and then utilize the Pick Lines option. This allows you to effortlessly select an existing line, such as the edge of a toposurface, to accurately place your wall along that defined boundary. This approach ensures a precise and quick placement, resulting in a clean wall along the topography's edge without the need for manual drawing or realignment.
Other Ways to Define Boundaries
While Pick Lines is the most common for existing geometry, Revit offers other tools for defining boundaries:
Drawing Tools
Located next to Pick Lines in the "Draw" panel, these tools allow you to manually sketch boundary lines when no suitable existing geometry is available.
- Line: Draw straight-line segments.
- Rectangle: Quickly create rectangular boundaries.
- Circle/Arc: Define curved boundaries.
- Polygon: Draw multi-sided shapes.
Pick Walls Tool
Some sketch-based commands, particularly for floors and roofs, also offer a Pick Walls option. This tool is specifically designed to quickly create a boundary from the center or faces of selected walls, making it ideal for laying out floor slabs or roof perimeters directly.
Room and Area Boundary Lines
For defining the analytical boundaries of rooms and areas, Revit provides dedicated Room Boundary Line and Area Boundary Line tools. These function similarly to other drawing tools but are specifically for analytical purposes and can also utilize the Pick Lines functionality.
Common Boundary Scenarios & Tools
| Scenario | Recommended Tool | Description |
|---|---|---|
| Creating a floor along existing walls | Pick Lines / Pick Walls | Select the edges of existing walls or the walls themselves to define the floor perimeter. |
| Placing a wall along a site boundary or toposurface edge | Pick Lines | Select a property line, grid line, or the edge of a toposurface for precise wall placement. |
| Defining a complex roof shape | Pick Lines / Draw Tools | Combine picking existing edges with drawing custom lines for unique roof designs. |
| Setting up room or area definitions | Room/Area Boundary Line | Use the dedicated boundary line tool, often combined with Pick Lines. |
| Creating an opening in a floor or wall | Pick Lines / Draw Tools | Define the perimeter of the opening by picking existing lines or drawing freely. |
