In the future most of us will be living in cities and due to climate change global average temperatures are expected to rise. As a result of the urban heat island effect, the temperature in cities can be up to 7 C higher than in the surrounding rural area. Higher air temperatures are not only uncomfortable, but also unhealthy especially for vulnerable groups such as elderly people. So there lies a challenge in making our cities adapted to climate change. One of the strategies of climate adaptation is the implementation of greenery. However, due to space constraints it is not always possible to plan urban parks. A relatively new trend is the integration of greenery into buildings. A significant amount of research has already been done on green roofs and green facades, but there is not a lot of knowledge available on green balconies. Vertical forests - buildings with full-sized trees on the balconies - can improve the local microclimate in the city by solar shading, evapotranspiration and wind flow change. By modelling the heat and moisture transfer of trees on balconies within the urban context, this research aims to evaluate the cooling benefits of green balconies on the local microclimate.