The Effect of Building Façade Materials in Mitigating UHI Effect: An urban city centre study

The rise of urban air temperature is significantly influenced by rapid urban growth. However, the research on using façade materials to enhance outdoor conditions is limited. Therefore, this research aims to use computational modelling utilising ENVI-met, a numerical simulation tool, to analyse the effectiveness of building materials in urban microclimates. A cluster of buildings in the urban centre of Newcastle upon Tyne was selected and full-force weather conditions were enforced for conducting simulations.

The model was validated against the measured air temperature and relative humidity using statistical indicators such as regression model R-squared, root mean square error (RMSE), and mean absolute error (MAE) for a typical summer day. The R-squared between the measured and simulated values shows a good agreement for air temperature (0.94) and relative humidity (0.95). RMSE and MAE statistical indicators also show a good agreement for air temperature.

Furthermore, the analysis was conducted for façade materials properties such as high solar reflectance, high thermal emittance, and high specific heat capacity. On a representative summer day, it is observed that the urban air temperature can be reduced up to 1.4 °C by implementing high solar reflective coating, potentially mitigating the UHI effect and enhancing urban thermal comfort.