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When making homes more sustainable, the emphasis is on scaling up to achieve the climate and energy objectives. Little attention is paid to air quality in homes, despite the fact that an estimated 98% of the Dutch homes do not meet the WHO's 2021 annual guideline value for PM2.5. Tackling sustainability and the indoor environment hand in hand is therefore important.

More than 70% of the dwellings in Chile were built before 2000, when the use of thermal insulation in the roofs of residential buildings became mandatory. This explains why less than 2% of dwellings are considered energy efficient. Social housing is no exception. Several studies have shown poor thermal performance of the envelope of social housing throughout the country, with low levels of thermal comfort and indoor air quality that affect the health of its occupants.

The Performance 2 project (2020-2024) is a French national research project that aims to evaluate the long-term performance and durability of Humidity-based Demand Controlled Ventilation (DCV) systems installed in two multi-family social housing buildings, located in Paris and Villeurbanne, France.

This study evaluates the performance of Single-Flow and Dual-Flow ventilation systems in a residential building situated in Strasbourg, characterized by high PM2.5 levels, permeable tightness, and strong wind conditions. The research examines indoor air quality by measuring CO2 and PM2.5 concentrations in bedrooms and compares the energy consumption of both systems across different cities.

More and more single-family houses are being retrofitted to achieve better energy efficiency levels. In this retrofitting process, the building envelope's airtightness is usually improved, and a ventilation system becomes necessary to create and sustain a healthy indoor air quality (IAQ). However, in France, as in many other western countries, ventilation requirements exist for new dwellings but not for residential retrofitting.

Radon gas is the second biggest cause of lung cancer after smoking and is directly linked to approximately 350 lung cancer cases in Ireland each year. It is a serious public health hazard, and the Government has published a National Radon Control Strategy to tackle the problem. The most cost-effective way of protecting the population from radon is to ensure that new dwellings are built to prevent the entry of this gas from below the building.   

Increasing indoor ventilation has the potential to dilute indoor radon and may be an appropriate first step when measured indoor radon concentrations are close to the mitigation threshold for an existing low-rise house that lacks balanced mechanical ventilation. A ventilation system that includes a heat exchange core is recommended in cold climates to reduce the energy loss associated with replacing stale indoor air with outdoor air that must be either cooled or heated to maintain thermal comfort.

The ingress of naturally occurring radioactive radon gas from the soil into buildings can occur both by convection through any openings in the foundations as a result of pressure differentials and by diffusion across an airtight barrier (World Health Organization 2009). Residential ventilation systems and exhaust devices can affect indoor radon concentrations if they result in depressurization of the conditioned spaced relative to the outdoors or to the soil below the foundations or if they supply outdoor air directly.

Radon, a naturally occurring radioactive gas, is a leading cause of lung cancer and has the potential to increase significantly due to current renovation strategies. Understanding the factors influencing radon infiltration into buildings is vital. Radon flux into buildings is a highly dynamic process influenced by various factors. The current study analyses a historical time-series dataset to determine radon entry rates into buildings and identify statistical factors driving the radon flux based on meteorological, environmental, and building characteristics.

The increasing severity and duration of climate change is that extremes – notably heatwaves, increases the risk of human thermal stress in indoor environments where people spend most of their times. Recent field measurements have demonstrated significant overheating in the EU building stock in the EU, characterized by well-insulated and air-tight envelopes. This exposes vulnerable communities to increases mortality risks that is bound to only get worse with an ever-worsening climate warming.