Outdoor Comfort UTCI

Outdoor Comfort UTCI is a Grasshopper tool for Rhino that helps you analyse and visualise outdoor thermal comfort using the Universal Thermal Climate Index (UTCI).

The definition combines local weather data, site geometry, solar exposure and Mean Radiant Temperature to calculate UTCI conditions across an outdoor surface. Results are displayed as a colour-mapped mesh, making it easy to compare hotter and cooler areas and understand how buildings, shade and site conditions affect outdoor comfort.

Useful for landscape architecture, urban design and architectural studies where thermal comfort needs to inform early design decisions.

What you can do

• Analyse outdoor thermal comfort using UTCI
• Use EPW weather data for your project location
• Define a specific analysis date and time period
• Include surrounding buildings and context geometry
• Calculate solar Mean Radiant Temperature
• Adjust analysis height above ground
• Visualise UTCI values as a colour-mapped mesh
• Define custom hot and cold thresholds
• Bake the resulting analysis mesh into Rhino

Version 2.0.0

The script has been substantially updated and rebuilt for Ladybug Tools 1.10, including updated components, improved organisation, clearer instructions and refreshed documentation.

Requirements

• Rhino 8
• Grasshopper 1
• Ladybug Tools 1.10
• Rhino model units: metres
• EPW weather data

Included

• Outdoor Comfort UTCI Grasshopper definition
• README
• CHANGELOG
• LICENSE

License

Single-user commercial license.

You may use the tool for your own work and commercial client projects. Sharing, redistribution, resale or team-wide use is not permitted.

See the included LICENSE file for full terms.

Current version: v2.0.0

Build date: 2026-08-27