The outdoor thermal microclimate is essential for the occupants’/pedestrians’ perception of the local environment of any high-end site or development. Improving the outdoor comfort conditions is directly related to the value of the properties within and a positive perception of the environment. The site’s environmental conditions can be evaluated through numerical modelling in terms of industry-accepted thermal comfort indexes. Areas of low comfort levels can be identified, mitigation measures proposed, and subsequently validated through numerical modelling.

Outdoor thermal comfort modelling is a multi-physics subject, requiring interconnection between environmental parameters. Microclimate conditions should be studied at a small-scale level, considering the incident solar radiation and weather conditions at the site (local wind speed, air and mean radiant temperatures and relative humidity), together with the thermal properties of the buildings and exposed surfaces within the immediate surrounding area. Industry-accepted thermal comfort indexes used in the SoftSim engineering practice are:

• Universal Thermal Climate Index (UTCI),
• Web Bulb Globe Temperature (WBGT),
• Standard Effective Temperature (SET),
• Wind Chill Factor,
• Heat Stress Index
• And others.