Climate heat waves occurring in urban centers are a serious threat to public health and wellbeing. Historically, most heat-related mortalities have arisen from excessive overheating of building interiors housing older occupants. This paper developed an approach that combines the results from building simulation and bioheat models to generate health-based limit criteria for overheating in long-term care homes (LTCHs) by which the body dehydration and core temperature of older residents are capped during overheating events. The models of the LTCHs were created for buildings representative of old and current construction practices for selected Canadian locations. The models were calibrated using measurements of indoor temperature and humidity acquired from monitoring the building interiors and the use of published building energy use intensity data. A general procedure to identify overheating events and quantify their attributes in terms of duration, intensity, and severity was developed and applied to LTCHs to generate the limit criteria. Comparing the limit criteria from the proposed and comfort-based methods showed evident differences. The proposed method predicted the overheating risk consistent with the overall thermal comfort during overheating events in contrast to the comfort-based methods. The new limit criteria are intended to be used in any study to evaluate overheating risk in similar buildings.

Climate change and urban heat islands are intensifying the frequency and severity of heatwaves, emphasizing the need for resilient and sustainable strategies to cool urban outdoor and indoor spaces. Urban trees are identified as an effective solution, yet limited studies address how different tree deployment strategies enhance building thermal resilience against heatwaves. This study examines the impact of strategic urban tree deployment on building thermal resilience across a neighborhood in London, Canada. Two deployment strategies are assessed: a straightforward strategy based on outdoor temperature hotspots, and a more complex strategy based on building indoor heat stress. The analysis incorporates tree growth and its effect on canopy coverage. A coupled microclimate-building performance simulation evaluates outdoor and indoor thermal conditions, with thermal resilience quantified using a novel method integrating microclimate effects, heat stress intensity, and exposure duration. Results indicated that when canopy coverage increases from 6% to the Nature Canada-recommended 30%, both strategies achieve similar maximum reductions in building surrounding outdoor air temperature (4.0 °C) and Standard Effective Temperature (6.9 °C), as well as comparable reductions in indoor thermal stress. However, at lower canopy coverage levels (≤20%), the indoor based strategy achieves a more uniform resilience distribution and enhances thermal resilience for the majority of buildings with poorer baseline conditions. At 30% canopy coverage and above, the differences between the two strategies become less pronounced, making tree deployment based on outdoor temperature hotspots a straightforward yet effective strategy for improving neighborhood thermal resilience.

Overheating in school buildings can negatively affect the cognitive learning performance of particularly young students whose thermoregulation systems are still developing. However, currently, in schools, issues related to overheating have been addressed by limiting the exposure time to thermal discomfort. In this paper, the development of a general procedure that combines building and bioheat simulations to evaluate overheating risk in schools and generate health-based overheating limit criteria that may be applied in Canadian schools is described. General school building models, having either old or new constructions, were created based on a primary school building and successfully calibrated using field measurements of indoor temperature and humidity and published building energy use intensity data. Three sets of two limit criteria (exposure duration and severity of overheating) that account for the personal exposure conditions of students in primary, middle, and secondary schools were developed by limiting the body dehydration of students during extreme overheating events. Comparing the proposed limit criteria with the hour of exceedance criterion revealed interesting relationships between them, suggesting the proposed limit criteria as a benchmark for the comfort-based criteria, particularly for the more vulnerable primary and middle schools. The proposed procedure with the obtained overheating limit criteria is intended to be applied in any field or simulation study to assess the risk of overheating in similar school buildings under any local prevailing climate.