climate change

Naturally ventilated (NV) buildings, when well designed and operated, can provide adequate indoor environmental quality (IEQ) while reducing the building energy demand. However, in dusty outdoor air, this ventilation technique may increase the penetration of outdoor particulate matter (PM) indoors, leading to adverse health effects. Given the increasing frequency of outdoor dust episodes in Mediterranean climates, an important research question is whether NV buildings can provide adequate indoor air quality (IAQ) during increased outdoor air dust episodes.

Nowadays, due to climate change, heatwaves become stronger in terms of frequency and intensity. This phenomenon can have serious impact on the indoor environments, indoor thermal comfort and on public health. These situations of high indoor thermal conditions can expose the occupants to health risks such as hyperthermia, dehydration, and heat strokes. Then, the estimation of these risks is crucial. The currently used indices to estimate health risks such as WBGT, HSI and PHS are generally dedicated to outdoor environments and for subjects exerting heavy activities.

Due to climate change, Western Europe is experiencing a surge in cooling demand, leading to higher summer temperatures accompanied by longer and stronger heat waves, thereby intensifying the toll on our buildings. This signals the need for architects to design buildings that take advantage of passive technics to provide thermal comfort. In recent years, natural ventilation has become a widely used method for reducing energy consumption and expenses. However, the utilization of natural ventilation can be restricted due to heatwaves and the impacts of climate change.

Urban settings and climate change both impact energy use, thermal comfort and ventilation of buildings. This is more noticeable in hot urban areas where the urban heat island effect is more pronounced; also, in densely built urban areas where thermal comfort in naturally ventilated buildings is affected by changes in natural ventilation rates because of surrounding obstructions. In some cases, overshadowing might alleviate the impact.

Mitigating the risk of overheating and associated thermal discomfort inside school classrooms is a global concern due to its significant impacts on students’ academic performance, health and wellbeing. Thus, rising ambient temperatures resulting from climate change can be challenging, especially in low energy schools designed to optimise their heating season performance. According to recent studies, many low energy school buildings fail to meet comfort standards and experience overheating, resulting in low student productivity and the need for using air conditioning systems.

Building designs to be in line with energy efficient and carbon reduction goals, often focus on energy efficient techniques like high insulation, airtightness. However, these buildings are often subjected to overheating risks due to unforeseeable events like frequent heatwaves and power outages even in moderate climate zones like Belgium. Overheating risks in residential buildings have negative impact on the health of the building occupants (especially on the vulnerable occupants like elderly, infants and sick persons), causing sleep deprivation, heat stress and even mortality.

In future years the frequency, duration and magnitude of extreme heat events, such as heat waves, is expected to increase due to climate change. The population is exposed to higher thermal discomfort and risk at home and, at the same time, high external temperatures make it more difficult to cool their household through natural ventilation.

In order to propose adaptive measures, research should first assess the thermal resilience of the existing residential buildings when exposed to prolonged heat stress. Poorly insulated and non-equipped buildings typical of Southern

By 2050, the entire built environment must be climate neutral. Before that final date, we have to find an alternative to the use of fossil energy in the built environment. The switch to a climate neutral built environment requires an integrated approach, focusing on switching to alternative, non-fossil fuels and on reducing the energy demand by taking energy efficiency measures.