New Wires and Cables in Revit 2026

Revit 2026 introduces a new approach to electrical circuits: you can manually specify conductor sizes and configure cables for individual projects. This is a feature many users outside the United States have long requested.

What Were the Previous Limitations?

Earlier Revit versions had four main limitations when configuring conductors:

All sizes were based on the US AWG standard, with no alternatives.

Sizing was automatic, without considering national codes or project-specific requirements.

Non-power circuits could not be configured, for example, to specify a cable category such as Cat-6 for Ethernet.

All conductors were treated as single-core; multicore cables were not supported.

These limitations have now been removed. Instead of automatic sizing, users specify conductors, materials, and insulation types and create cable configurations for specific loads. This expands applications and enables automation through Dynamo or the API.

New Settings

The new Electrical Conductor and Cable Settings panel is available under Manage > MEP Settings and includes four tabs:

Conductor Details — specify materials, temperature ratings, and insulation types.

Conductor Sizes — define conductor names and diameters yourself (for example, #12 = 0.0808 in, 1.5 mm² = ~1.382 mm).

Cable Sizes — create standard cable configurations (for example, 1 hot, 1 neutral, and 1 ground conductor for 20A).

Cable Types — create cable types with a material, insulation, temperature rating, and sizes from the preceding tab.

How Does It Work in Practice?

Create a cable type, describe its composition, and assign it to the appropriate circuit. This approach works with both commercial cables and project-specific cable assemblies, including feeder circuits, transformers, and panel assemblies.

When older templates and models are upgraded, conductor settings are automatically migrated to the new structure. Schedule and tag parameters are retained, but now use the Cable Type and Cable Size terms.

Automation Opportunities

Removing built-in automatic sizing is not necessarily a loss: it makes room for custom logic. For example, you can define a rule that automatically assigns the required cable to every 20A circuit. Through the API or Dynamo, you can retrieve cable types (GetCableTypeIds), access available sizes (GetUsableCableSizeIds), and assign a cable to a specific circuit.

What Was Removed?

The old settings are no longer available:

NEC wire sizes (including temperature and voltage drop adjustments);

Global ambient temperature;

Automatic voltage drop sizing;

Impedance tables (previously read-only);

Neutral and ground settings (moved to families, with no effect on calculations).

The Takeaway

You now choose conductors and cable configurations to meet project requirements. Revit is more flexible, easier to understand, and closer to actual design practice. If you work to European, Asian, or local standards, this update is worth learning.