Domestic overheating risks and mitigation strategies: The state-of-the-art and directions for future research

Anthropogenic climate change will likely put dwellings at risk of overheating and potentially increase cooling demand in the decades ahead, leading to higher greenhouse gas (GHG) emissions due to the energy consumed for mechanical cooling. Contemporary constructions with highly insulated fabric have been found to suffer from periodic overheating in today's climate, the occurrence of which is projected to increase in frequency as the temperature rises. This critical review investigates the factors affecting overheating risks in dwellings and passive cooling strategies to mitigate overheating impacts on occupant thermal comfort and wellbeing. The cooling efficiency of passive strategies is affected by the design, construction and operation of buildings, as well as climate and occupancy. A framework has been developed to illustrate the effect of overheating factors on the cooling efficacy of passive strategies. Findings suggest that a combination of passive strategies is required to minimise overheating risks by the 2080s. External solar shading is the most effective method for retrofitting insulated dwellings. On the other hand, cool paint is ideal for uninsulated dwellings. In addition, thermal mass and natural ventilation require occupant interaction for optimal air circulation and cooling performance.