Creating Corner Condition for Curtain Wall in Revit: A Step-by-Step Guide

Let's return to level two for this next phase—working in floor plan view offers significantly more precision and control when positioning these elements compared to navigating in 3D space. The key technique here involves selecting what we call a "window," which refers to the entire assembly of hosted elements that move together as a unified group. When you select this assembly and copy it from one reference plane to another, you'll encounter the same geometric conflict warning we discussed earlier.

Rather than manually resolving this warning repeatedly—a time-consuming workflow that interrupts your design momentum—we'll implement a more efficient approach through the curtain wall's type properties. Navigate to the type properties and enable automatic embedding. This configuration change eliminates the recurring error messages and removes the need for manual cut-and-join geometry operations with each copy. With this setting active, you can select both elements and either copy them systematically from gridline to gridline, or leverage the mirror pick axis tool to reflect them across into the adjacent bay—both methods will execute cleanly without interruption.

Continue this mirroring process into the next bay, keeping in mind that our objective at this corner is achieving a seamless join between the two curtain wall segments. To accomplish this, select both assemblies and use either the mirror pick axis tool or mirror draw axis tool, positioning your mirror line at precisely 45 degrees from the grid intersection point. This angular approach creates the corner condition we're targeting, though you'll need to verify that all elements align correctly with your design intent before proceeding.

Quality control is essential at this stage, so run quick dimensional checks to confirm accurate positioning across all elements. Once you've verified the alignment, use the trim extend function to clean up the corner intersection. While the temporary dimensions served their verification purpose, you can delete them now to clear your workspace. The next critical step involves establishing a reference plane positioned exactly two feet from the gridline—this will serve as the precise location for your mullion installation.

Streamline this process by mirroring your initial reference plane rather than drafting a new one from scratch, which immediately provides both corner reference points. With these guides in place, navigate to the Architecture tab, select Curtain Grid, and add your grids directly into position using these reference points as your guide.

Switching to 3D view reveals the successfully created corner condition, though—as expected from our previous work—this will require some profile editing to achieve the final refined appearance. The corner is structurally sound but needs the detailed finishing touches that separate professional-grade work from rough drafts.

Execute the edit profile command to refine the corner geometry. This process relies heavily on the pick lines tool to identify the specific curtain wall points that will serve as your geometric references. Combine this with strategic use of the split tool and trim extend corner function to systematically clean up any irregular intersections or overlapping geometry. Complete the sketch to lock in these refinements.

The result is a properly executed corner where both curtain wall segments meet cleanly, with only the final mullion installations remaining. For this particular configuration, focus on the gridline segment since all other structural elements are already properly positioned and aligned.

You can safely delete the corner mullion that may have been automatically generated—this element won't require unpinning due to the methodical way we constructed this assembly. Unlike the storefront type that automatically generates mullions (which can create constraints), our manual approach provides complete control over mullion placement. Create the corner mullion using the five-by-five specification to complete the structural framework.

Return to level two for a final verification that all joints executed correctly and completely. Assuming the connections are solid—which they should be given our systematic approach—perform any necessary final trimming to ensure clean intersections. With this corner assembly completed successfully, you're now ready to address the remaining curtain wall segments along the C to D and A, B, C, and D gridlines using these same proven techniques.