The influence of urban microclimate vertical variations on the building performance of a high-rise office building at different floors

Abstract

This paper explores the urban microclimate effects on the building performance of high-rise office buildings of different heights. In general, the environment section of buildings’ performance calculation relies on weather station data located in rural areas which are quite different from the actual urban microclimate. How the accuracy of urban microclimate modelling affects the building performance simulation is not understood. We have previously explored horizontal elements’ effects on high-rise office building performance. In this research, wind and temperature vertical variations’ effects on performance at different heights is explored. Compared with the wind in rural areas, the urban wind has more barriers and is more turbulent. The temperature profile in urban areas is also different from that in rural areas because of Urban Heat Island effects. How do these features of urban microclimate influence the performance? Is the influence significant enough and worth modelling? From this research, vertical temperature gradients are a more significant influence on energy use than vertical variation of wind speed and urban boundary layer depth. If the building is extremely high the accurate modelling of wind speed profile may matter as well because the influence of vertical variations on natural ventilation increases with height.