With the release of Revit 2026, Autodesk has introduced several updates and improvements across the platform. However, one notable change stood out specifically for electrical engineers, not because it was highlighted, but because of its quiet removal. Without much attention, Autodesk eliminated the voltage drop calculation feature from Revit.
This change marks a significant shift in how Revit supports electrical design and raises important questions about the future of BIM for electrical engineers.
The Role of Voltage Drop in Electrical Design
In the context of electrical design, voltage drop calculations are a core component of ensuring that systems perform as intended. They directly affect wire sizing, circuit integrity, and compliance with design standards. As part of the broader BIM workflow, voltage drop represents one side of what we often refer to as the electrical design triangle that include the 3D model, single-line diagrams, and engineering calculations.
Each of these elements is necessary for a complete and reliable electrical design process. When Revit removed the ability to calculate voltage drop, it effectively eliminated one side of that triangle.
The History of Voltage Drop in Revit
Voltage drop has been available in Revit for many years, but its implementation has always been limited and flawed:
- Wire lengths used in calculations were poorly estimated and could not be easily verified.
- Only copper wires were supported, excluding aluminum and other conductor types.
- Engineers couldn’t override calculated wire sizes or adjust impedance values.
- The wire sizing function was tied to these voltage drop calculations, which further limited its usefulness.
As a result, many engineers simply ignored the feature altogether. It became a checkbox that few trusted and even fewer used in production workflows.
Autodesk’s Decision
Given these limitations, Autodesk faced three potential paths. They could leave the feature and its shortcomings as it was, fix and modernize the feature to align it with real-world engineering needs, or remove it entirely to simplify the software and eliminate a feature that was functionally obsolete.
For many years, Autodesk took the first approach, leaving voltage drop in place without updating or improving it. In Revit 2026, they chose the third option: to remove it altogether.
Interestingly, Revit 2026 did include some progress toward improving wire sizing. Engineers can now define wire sizes more flexibly, a long-awaited enhancement. However, Autodesk did not take the final step of integrating impedance data into those wires for accurate voltage drop calculations. Instead, they stopped short and removed the calculation feature entirely.
What This Means for Electrical Engineers
The decision to remove voltage drop leaves a clear gap. Electrical engineers now need to look elsewhere for critical components of their design workflow, particularly for voltage drop and related calculations.
A Purpose-Built Solution
At Design Master Software, we recognized this limitation over a decade ago. In 2014, we began developing ElectroBIM specifically because Revit’s voltage drop functionality was insufficient. ElectroBIM is built to provide the calculations Revit does not, while integrating tightly with the Revit model.
In addition to voltage drop, ElectroBIM offers other essential electrical design tools, like single-line diagram generation, fault current calculations, and arc flash analysis
The Bottom Line
While Autodesk’s decision to remove voltage drop may simplify Revit’s electrical toolset, it also highlights a long-standing limitation in the platform. For firms looking to maintain a BIM-based workflow that includes all aspects of electrical design, third-party tools like ElectroBIM are essential.
Join Our Free Webinar
June 25, 2025 • 1:00 ET / 10:00 PT
“Create Single-Line Diagrams in Revit Without Late Nights or Change Orders”