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Residents of the dense urban environment in Hong Kong suffer from poor living conditions due to building overheating, especially during near-extreme summer conditions. In this study, the thermal comfort and energy performance of typical public rental housing (PRH) building types were simulated using DesignBuilder. Results show that the oldest Slab type PRH, which has a compact building form, has the highest indoor air temperature, yet the lowest cooling energy demand. On the other hand, the Trident type PRH, with the largest external wall U-value, performs the worst overall and is the most responsive to outdoor temperature changes.

This study investigated the potential negative impacts of future UK climate change on dwellings. In particular, the risk of overheating was considered for a Passivhaus dwelling in London. The study used dynamic simulation modelling software to investigate the potential use of building geometry to control current and future overheating risks in the dwelling for London climate. Specifically, the focus was on the optimum inclination of a south facade to make use of the building's shape to self- protect itself. A range of different inclined facades were examined to test their effectiveness in reducing the overheating risk. The research found that implementing a 115° tilted facade could completely eliminate the risk of overheating in current climate, but with some consequence for natural ventilation and daylighting. Future overheating was significantly reduced by the tilted facade. However, geometric considerations could not eradicate completely the risk of overheating particularly by the 2080s. The study also used CFD modelling and sensitivity analysis to investigate the effect of the facade geometry on the wind pressure distributions on and around the building surface. This was done to assess natural ventilation flows for alternative facade inclinations.

The Passivhaus strategy employs super insulation to reduce the heat transfer through the building envelope. It has been argued that super insulated homes are vulnerable to summer overheating risks, even in the current climate. The UK is expected to experience hotter and more extreme summers in the coming decades and the risk of buildings overheating may become very significant in future climate scenarios. The Passivhaus approach can use much of the solar energy from its relatively large glazing in south facade but this large glazing may eventually lead to overheating in summer time. The study used parametric design modelling to generate differently inclined facade geometries for south elevations. Each elevation was then simulated by means of dynamic building simulation software in order to examine to what extend inclined wall mitigate summer overheating risk for Passivhaus dwellings in the UK under alternative future weather projections.