overheating

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.

PCM (phase change materials) is an innovative technology and an effective method for improving the thermal mass of buildings owing to it possesses the property of large thermal capacity within a limited temperature range, which is similar to an isothermal energy tank. However, most of the previous studies focused on the combination of PCM and walls that the utilization potential of rooftop is lack of concern though there is a significant amount of heat gains from rooftop.

Airtight and highly insulated buildings are subjected to overheating risks, even in moderate climates, due to unforeseeable events like frequent heatwaves and power outages. Educational buildings share a major portion of building stocks and a large percentage of the energy is expended in maintaining thermal comfort in these buildings. Overheating risks in educational buildings can lead to heat-stress and negatively impact the health conditions and also cognitive performance of the occupants.

The use of the word “resilience” has increased significantly since 2010, however, there is a lack of understanding around 1) how thermal resilience is defined (where some definitions were offered only recently) and 2) what distinguishes it from typical overheating assessments. In addition to this, there is a lack of uptake in the remote monitoring industry (which uses low-cost solutions) when it comes to typical parameters used in thermal comfort studies and there is need to demonstrate how resilience performance can be reported going forward.

Overheating in buildings is expected to increase as global warming continues. This could lead to heatrelated problems ranging from thermal-discomfort and productivity-reduction to illness as well as death. From the indoor-overheating point of view, the sensitivity of 9,216 Dutch dwelling-case to the climate change is quantified and ranked using detailed simulation and post-processing calculations. The results show that the sensitivity depends significantly on the dwelling’s design/operation characteristics. Minimally-ventilated dwellings are the most sensitive ones.

The increasing number of highly insulated and air tight buildings leads to the concern of indoor environment overheating and related comfort and health issues. This can already happen in a temperate climate as found in the Netherlands. This work studies the ventilative cooling process as a possibility to avoid overheated dwellings. A monitored dutch passive house was modelled in Trnsys and the impact of increasing air flow rates on indoor temperatures was simulated. The most overheated zone was chosen to be analysed.