When working with building information modeling (BIM) software like Revit, creating accurate 3D representations of your building model is crucial. Adding dimensions to objects in 3D view can help in providing a better understanding of the spatial relationships between different building elements. Here are the steps to add dimensions in a 3D view in Revit:

Step 1: Open the 3D View

First, open the 3D view in Revit by navigating to the desired view in the project browser or by creating a new 3D view.

Step 2: Select the Objects

Next, select the objects to which you want to add dimensions. You can choose individual elements or a group of elements that you want to dimension.

Step 3: Activate the Dimension Tool

Once the objects are selected, activate the dimension tool by clicking on the 'Annotate' tab in the ribbon, and then select 'Aligned' or 'Linear' dimension, depending on the type of dimension you want to add.

Step 4: Place the Dimensions

After selecting the desired dimension type, place the dimensions by clicking on the points where you want to measure the distance or length. Revit will automatically snap to the endpoints or midpoints of the selected objects, making it easier to accurately place the dimensions.

Step 5: Customize the Dimensions

You can customize the appearance of the dimensions by adjusting the text size, style, and other properties through the dimension style settings. This can help in making the dimensions more readable and consistent with the project standards.

Step 6: Add Additional Dimensions

Repeat the process to add dimensions to other objects in the 3D view as needed. You can also add dimensions in different planes to represent vertical or horizontal distances.

Step 7: Review and Modify

Once the dimensions are placed, review the 3D view to ensure that all necessary dimensions are added and are accurately representing the spatial relationships between the objects. You can modify the dimensions by dragging the witness lines or dimension text if needed.

Adding dimensions in 3D view is a valuable practice in architectural and engineering projects where precise spatial coordination is crucial. It not only enhances the visual representation but also aids in the accurate construction of the building. By following these steps, you can effectively add dimensions to objects in the 3D view in Revit, and improve the overall quality of your BIM model.