MEP Families for Ceiling Coordination
The family editor remains a mysterious feature for many users of Autodesk® Revit®. However, there are edits that you can easily make to families to make them more useful in projects. This article will show you how you can use the family editor to make families better for ceiling coordination.
Many Revit MEP families, especially in the electrical discipline, display an annotation symbol rather than an actual physical size. While this is perfectly acceptable for plans for construction documentation, it is not so useful for coordinating ceilings. Have you ever gotten the request from an architect to see the actual device outline rather than the symbol? For example, a CCTV camera is usually a small round object, but the plans show a symbol for the camera (see Figure 1).
Have you wondered how you will accommodate the request?
Figure 1: An annotation symbol
It can be done with some simple editing of your families. The heart of the technique is to leverage Revit's detail levels. Many firms set plan views for construction documentation to a detail level of either Medium or Coarse. It is natural to reserve the Fine detail level for, well, fine tasks. Ceiling coordination fits the bill!
One technique I have seen is to turn off the annotation family at Fine level and to turn off the display of the 3D model at Medium and Coarse levels. There are several reasons why this approach is not good.
- This effectively reduces the possible displays of the family to only two choices rather than three. You have the choice to display the 3D model at Fine and the symbol at either Medium or Coarse. Is that so bad? Yes, if you want elevations and sections to NOT show small elements at Coarse detail level.
- Any elevations, sections, or 3D views would need to be set to Fine in order to see the 3D elements.
- If there are multiple 3D elements that make up the model, they all need to be set to the same visibility settings in order for all the 3D elements to be visible at the same time.
- Displaying 3D work in plan views is a known performance issue and should be avoided when possible.
The alternative approach is similar in that the annotation family is turned off at Fine detail level. The difference is that symbol lines are used to display the outline of the device at Fine detail level rather than the 3D elements. This approach addressed the shortcomings noted earlier.
- You still have three detail levels to work with in case you want to hide features at the Coarse detail level.
- You can use any detail level you want for elevations, sections, and 3D views.
- You can create just an outline of the element rather than all the details.
- The symbol lines are all that show in plan views at Fine detail level, keeping model performance at an acceptable level.
Finding a Family to Edit
Although you can use any family (with a nested annotation family) intended for ceilings with these instructions, you may want to download the sample Revit 2012 family posted in the AUGI forums to follow the steps. The family is located in the Revit MEP – Families forum under the thread titled “Sample Family for AUGIWorld Feb 2013.” The name of the family is “CCTV Camera (Ceiling).”
If you choose to use your own family the names of the views could be different. But as long as your family is using a nested annotation family for the plan symbol and not showing 3D objects in a plan view it should work for the purpose of this article.
I suggest placing the family file on your desktop while following the steps in this article to avoid accidental overwrites of your live families.
Testing the Initial Family
Start a new instance of Revit. Open a new Revit project to test your family edits. For this discussion, all you need is an open ceiling view with a single ceiling placed. The easiest way to do that is to:
- Open a ceiling view.
- On the ribbon, select the Architect tab > Build panel > Ceiling tool.
- On the ribbon, select the Modify | Place Ceiling tab (if it is not active) > Ceiling panel > Sketch Ceiling tool.
- On the ribbon, select the Modify | Create Ceiling Boundary tab (if it is not active) > Draw panel > Rectangle tool.
- Draw a rectangular boundary at least 10’ 0” by 5’ 0”.
- On the ribbon, select the Modify | Create Ceiling Boundary tab (if it is not active) > Mode panel > Finish Edit Mode tool.
- Open the family in Revit.
- On the ribbon, select the Family Editor panel > Load into Project tool.
- Place an instance of the family on the ceiling (the sample family is a face-based family so be sure to select the Place on Face option on the ribbon).
Now change the Detail Level to Coarse, then Medium, then Fine. The symbol is visible in all three levels of detail (at least for the sample family, if you are using your own family the results may vary).
Leave this test project open to continue testing as you work on the instructions.
These instructions are written using Autodesk® Revit® MEP 2012, so the steps might vary slightly in other versions of Revit.
- Switch to the family in Revit.
- Open to the Floor Plans > Ref. Level view.
- Select the nested annotation family placed in the view (see Figure 2).
- In the Properties pane, select the Edit… button for Visibility/Graphics Overrides.
- Clear the Fine option for Detail Levels (see Figure 3).
Figure 2: Select the Annotation Family
Figure 3: Turn off “Fine”
6. Select OK.
7. On the ribbon, select the Load into Project tool.
8. In the Family Already Exists dialog box, select the Overwrite the existing version option.
9. Change the view’s Detail Level to Fine. The symbol should disappear.
10. Change the Detail Level to Medium. The symbol should reappear.
11. Switch to the family in Revit.
12. On the ribbon, select the Annotate tab > Detail panel > Symbolic Line tool.
13. On the ribbon, select the Modify | Place Symbolic Lines tab (if it is not active) > Draw panel > Circle tool.
14. Place the cursor over the outer circle and type SC to snap to the center of the existing circle.
15. Select the outer circle to specify the center point.
16. Select the outer circle again to specify the radius.
17. On the ribbon, select the Select panel > Modify tool.
18. Select the symbolic circle you just created.
19. In the Properties pane, select the Edit… button for Visibility/Graphics Overrides.
20. Clear the Coarse and Medium options for Detail Levels (see Figure 4).
Figure 4: Turn off “Coarse” and “Medium”
21. Select OK.
22. On the ribbon, select the Load into Project tool.
23. In the Family Already Exists dialog box, select the Overwrite the existing version option.
24. Change the view’s Detail Level to Fine. The circle indicating the actual outline of the element should appear.
25. Change the Detail Level to Medium. The symbol should reappear and the circle should disappear.
As you can see (Figure 5), you now have a family with the capability to show the actual geometry of an element at Fine level of detail, even when the element normally shows a symbol at other levels of detail.
Figure 5: The results
I’m Not Quite Done Yet
The symbolic circle that we added hasn’t really been tied to the geometry of the family. For example, if you change the Base Radius parameter in the family to 4” instead of 3 1/16” you will see the symbolic circle does not automatically adjust.
This can be easily corrected.
- Switch to the family in Revit.
- Select the symbolic circle and change its radius to 5” or some other larger value.
- On the ribbon, select the Modify tab > Modify panel > Align tool.
- Select the extrusion circle.
- Select the symbolic circle. The symbolic circle should adjust back to the size of the extrusion.
- Select the blue padlock symbol to constrain the symbolic circle to the extrusion circle. The padlock symbol should change to “locked” to constrain the symbolic circle (see Figure 6).
Figure 6: Add a constraint
Change the Base Radius parameter in the family to 4” instead of 3 1/16” and you will see the symbolic circle automatically adjusts to the new size.
You may have noticed that some of the elements in the family editor turned gray after you modified them. The grayscale is used to indicate elements that are not visible at the current detail level. The grayscale will only be evident in the family editor.
Modifying families so you can perform ceiling coordination is not difficult once you have done it a few times. The only issue you will run into is the tedium of changing a lot of families to enable this capability.