overheating

The Renson One residential concept focusses on the building envelope and the mechanical installations to ensure a climate-adaptive and resilient design throughout the year. Passive, renewable and energy-efficient elements are combined to address the total indoor environment and energy consumption, based on integrated control mechanisms. The high potential of external shading and ventilative cooling was proved to limit overheating and cooling consumption. Adding manual control of the windows to the simulations is a challenge to better approach reality.  

The EIA EBC Annex 80 Resilient Cooling program has focused on bringing together and extending the knowledge on the resilience of buildings to overheating (Holzer, 2024).  In the context of the Annex 80 Resilient Cooling program a research project, Recover++, has been setup to define a new resilience indicator, based on the properties and behaviour of real-world building projects under extreme climatological condition and shocks, as heatwaves under current and future weather conditions.

Project RESILIENCE set out to examine overheating in a variety of building archetypes, but also examined several aspects of overheating related to the tools that are used, the weather data that has been employed in dynamic simulations and potential low-cost solutions to improving the resilience of the existing non-residential building stock that relies upon ventilative cooling.

There is an increasing need to consider and evaluate the effect of existing ambient warmness on current low energy buildings to determine if current guidelines and standards are robust or resilient in the face of projected future warming. Thus far there is a lack of empirical evidence from low energy non-residential spaces where resilience metrics are seldom explored. The purpose of this presentation is to present the status on overheating from over 30 different low energy non-residential buildings located in Ireland.

Project RESILIENCE set out to examine overheating risk in a variety of non-residential building archetypes, but also examined several aspects of both overheating risk metrics and indoor thermal resilience evaluation criteria. Assessing the future risk of overheating in new and retrofitted buildings is usually undertaken by applying national regulations and buildings codes where minimum criteria is typically published.

Climate change has exacerbated the summertime overheating in buildings, necessitating resilient adaptation strategies. Based on our previous work, which introduced a Thermal Resilience Index (TRI) ranging from Class F to Class A+ using a concept of resilient trapezoid framework, this study explores unit-level retrofit strategies for high-rise long-term care buildings.

As a result of the new initiatives and regulations towards nearly zero energy buildings, designers are more frequently exploiting the cooling potential of the climate to reduce overheating and improve indoor well-being of people. At early stage of design, climate analysis is particularly useful for determining the most cost-effective passive cooling methods, such as ventilative cooling. However, besides the external climate conditions, building energy uses are characterized by occupancy pattern and needs, envelope characteristics and internal loads.

Overheating in school buildings is likely to lead to a negative learning performance experience for occupants in these settings. In Ireland, school buildings are primarily naturally ventilated, given the relative increases in external mean temperatures that are projected to have negative effects on the potential of natural ventilative cooling going forward, it is important to assess what the current overheating status is in these buildings. Existing work has already highlighted the lack of measurement data on overheating in low energy school buildings.

This study examines the impact of heatwaves on indoor operative temperatures of dwellings in Pamplona (north of Spain) and presents a comparative analysis of a typical summer and two extreme summers with heatwaves in 2003 and 2022. The assessment was conducted in two neighbourhoods with different urban morphologies and built periods related to different energy regulations in Spain. EnergyPlus was used to simulate each residential typology for 5 months in 8 different orientations and with the constructive characteristics that correspond to its built period.

Overheating has become a recurring problem in airtight and highly insulated buildings even in moderate climates. This study aims to analyze thermal comfort and thermal resilience in an office building during summer and mid-seasons by means of dynamic simulations. Thermal comfort assessment shows, this office building without improvements has a ‘good’ indoor climate for 79.6% of total occupied hours.