The Curtain Wall tool in Revit is one of the most versatile tools on the platform. One key feature is the ability to embed both opaque and translucent objects into a single Revit family. This procedure, however useful, is difficult to reverse. Especially when attempting to sort each object into the correct cove.tool view for the final export. The steps in this article help guide users to prepare their curtain walls for the exporting to the Windows and Exterior Walls categories.
Before we begin, make sure to have the latest Revit Plugin version 2.2.0, or later, installed on your local machine. The version and its subsequent updates include critical features to handle the complexities of the curtain wall models. Also, make sure you have read through the Ideal Revit Model and Things to Avoid in Revit articles as well for the best practice to prepare your whole Revit model as this article focused specifically on the Exterior Walls and Windows layers.
1. Export for Windows objects from a Curtain Wall family
For the Windows layer, all we want are elements that are transparent. However, when uploading a panel family that might be for a specific manufactured product, the individual elements that make up the model are not always available to manually select nor do they turn off with the visibility settings. When using a specific product as a curtain wall panel the panel family may not be properly subcategorized, and thus when unchecking the box in the visibility settings for "frame" it does not hide as shown below.
If your curtain wall panel exports like this, great! If it doesn't, it is more than likely because the frame and other non-glass elements are solid elements (sweeps, extrusions, etc.) that don’t allow area data to be extracted during the exporting process. Properly assigning these elements to the correct subcategory will let you turn off the frame and other elements so you only see the glass in the view. The glass also needs to be properly assigned to the glass subcategory so it can be turned off for exporting the Exterior Walls layer. Here are the key steps to adjust your Revit panel family to show in your visibility settings which will let you quickly hide everything appropriately.
1. Select the panel you want to edit and click on Edit Family in the ribbon under the Modify tab. You can also double-click the selected element. We're using a fixed window type for our example.
2. Once in the family model, select the elements that are not suppose to be glass. In the properties window scroll down and locate the subcategories fields under the header Identity Data as shown here.
3. If there is no text in the field check if the drop-down arrow provides any options. If not, type in the name that best describes the object(s) you have selected. Our example is Frame/Mullion as the subcategory.
4. Next, only select the element that is supposed to be glass. Repeat step 3 and assign the subcategory option to Glass.
5. Test that the subcategory properties are assigned correctly by typing VG/VV to open the visibility settings. Check and uncheck the various options and hit apply to make sure the correct elements turn on and off.
6. Once you have verified all elements are properly assigned to their subcategories, load the Revit family into your project. This will return you to your main project.
7. The only thing left is to now turn off the necessary elements with visibilities setting in your project view. Make sure you are in the cove.tool Windows layer and type VG/ VV to open visibility settings. Navigate to the Curtain Panels and open extend the subcategories by clicking on the + symbol next to the checkbox. Uncheck everything that is not Glass and click apply.
8. If you edited a fixed window type like in our example, the subcategories may be under the Window category like the example below. For the Windows layer uncheck everything under windows that is not Glass and click apply.
Your Windows layer view should look like the example below or it may have mullions turned "on". Having mullions "on" is acceptable, as the cove.tool plug-in takes care of those automatically. For some very large projects, they may need to be turned off or simplified if they continue to not export. Export the Windows layer geometry to cove.tool and your all set.
2. Exporting Exterior Walls from Curtain Walls
For the Exterior Walls layer, all we want are opaque elements. Somewhat unique to this workflow, however, you may need to unhide your curtain walls in the Exterior Walls layer if you have modeled your project walls as curtain walls. Modeling all of your walls as curtain wall types in Revit can be very fast, even if the walls are not intended to be curtain walls products. A common example of this workflow is designing modular façade systems for EIFS or Pre-Cast Concrete panels. Each modular panel type is designed as a Revit Family and then specified anywhere in the Curtain wall system, which makes it easy to update and maintain the BIM model. While fast and efficient in the beginning, if the key parameters are not provided early on, you can lose this efficiency in later development phases. Here are key steps to streamline your workflow to work efficiently with cove.tool plugin for easy exporting.
1. Ensure all families for your modular panel types have the same subcategories of Glass, Mullion, and Exterior Finish types. If these types are not present you may need to create them and assign them accordingly as described earlier in section 2.
2. In each cove.tool view for Exterior Walls and Windows, the unwanted layers can be quickly hidden using visibility settings (VG/VV), as shown below.
3. Exterior Walls (left) and Windows (right) visibility settings:
a. Glass not identified in the family on a subcategory.
b. Glass removed from all families.
The best BIM workflows take advantage of the power of well-organized data structures that use the computer to automate as much as possible and let the user touch just a few things to get a powerful scaled result. The recommended workflow is to leverage your visibility settings as much as possible when prepping your Revit model to work with cove.tool. This will ensure quick hide and unhide capability throughout your design phases and speed up the export process so you can get to the holistic performance results faster and more informed decisions along the way.