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Physiological modeling is important to evaluate the effects of heat and cold conditions on people’s thermal comfort and health. Experimental studies have found that older people (above 65 year old) undergo age-related weakening changes in their physiology and thermoregulatory activities, which makes them more vulnerable to heat or cold exposure than average aged young adults. However, addressing the age-related changes by modeling has been challenging due to their wide variability among the older population. This study develops a two-node physiological model to predict the thermal response of older people. The model is built on a newly developed two-node model for average-age young adults by accounting for the age-related attenuation of thermoregulation and sensory delays in triggering thermoregulatory actions. A numerical optimization method is developed to compute the model parameter values based on selected benchmark data from the literature. The proposed model is further validated with published measurement data covering large input ranges. The model predictions are in good agreement with the measurements in hot and cold exposure conditions with a discrepancy 0.60 °C for the mean skin temperature and of 0.30 °C for the core temperature. The proposed model can be integrated into building simulation tools to predict heat and cold stress levels and the associated thermal comfort for older people in built environments.

Hygrothermal simulation tools are commonly used to assess the moisture performance of building envelope components. Owing to the computational costs required to complete simulations over the long-term, one approach to reduce simulation time when undertaking hygrothermal design analysis, is to select representative year(s) amongst sets of long-term climate data. To properly select these moisture reference year(s), a method is required to rank the climate years in terms of their moisture severity. To this end, several methods have been proposed in the literature, amongst which is the damage function method as reported in ASHRAE Project Report RP-1325. In this method, a stepwise regression model was developed to predict the damage function, as characterized by the RHT-index (integral of (Temperature - 0) (Relative Humidity – 70%)), in an OSB layer of a wood-framed wall as a function of several average yearly climate parameters for a North facing wall. The model was calibrated using climate and simulation data for eight cities in USA and validated for four cities comprising Winnipeg, Canada. The method was found to be the most consistent and accurate amongst all ranking methods as have been evaluated. The objective of this paper was to: (1) evaluate the ASHRAE method for several Canadian locations; (2) determine whether the original model can be recalibrated in the event it is shown to be deficient; and (3) explore the potential of improving the model using other approaches such as the Partial Least Squares Regression (PLSR). The results suggest that for some Canadian locations, as were investigated in this study, the use of the original model may not be appropriate for prediction. However, the model was shown to perform better after it was recalibrated for Canadian locations but without improvement in ranking performance. Furthermore, the damage function model can be improved by using PLSR in terms of prediction and ranking., 2022 Buildings XV International Conference, December 5-8, 2022, Clearwater Beach, Florida, United States, Series: ASHRAE Conference Proceedings

The changing climate is affecting many aspects of the built environment. In respect to the wall assemblies of buildings, any change in the moisture load to the wall would influence its long-term moisture performance. Given that Wind-Driven Rain (WDR) is the primary source of the moisture load to the wall and that this load may also change as a result of changes to the climate in the future, it is expected then, that such changes will subsequently affect the moisture performance of wall assemblies. In this study, changes in moisture load of a vinyl-clad and a brick veneer-clad wall assemblies, located in 11 selected Canadian cities, subjected to climate data for two future projected climate scenarios, 2.0 °C (2034–2064) and 3.5 °C (2062–2092), as generated from the Canadian Regional Climate Model (CanRCM4), were assessed. Climatic parameters such as, WDR and Driving Rain Wind Pressure (DRWP), as well as their Intensity-Duration-Frequency (IDF) curves were analyzed and produced to determine boundary conditions for watertightness testing. The two analyzed wall assemblies were thereafter subjected to such tests, and the results of which were used to establish a two-step approach to estimate the moisture loads in these two wall assembly types based on hourly WDR load and hourly DRWP. Moisture loads of each wall assembly type during future projected climate scenarios were compared to those of the historical baseline periods. Increase in moisture load to both wall assembly types were found for most of cities analyzed in this study.

Buildings contribute to the urban heat island (UHI) phenomenon, but also have vast “un-used” surfaces that can be employed to incorporate innovative nature-based solutions (NBS) to mitigate UHI effects. NBS on buildings can be achieved by increasing surface reflectivity (ISR) on flat building envelop and increasing surface greenery/vegetation (ISG) on both vertical and horizontal building envelope components. This paper presents a snapshot of the current understanding of NBS and how they affect building performance, the simulations conducted to evaluate NBS and UHI effects and modeling approaches used, the primary knowledge gaps as well as the future steps needed to reduce the effects of UHI in urban agglomerations across Canada. The road map consists of; I) providing approaches to lessen the UHI influences with respect to the implications of warming/changing climate, urban canopy/landscape characteristics and building design; II) development of the best management practices (BMP) for NBS – UHI for Canadian communities; and III) guideline for the design of NBS–UHI solutions to mitigate UHI in accordance with Canadian design climatic load., COBEE 2022, 5th International Conference on Building Energy and Environment, July 25-29, 2022, Montreal, QC, Canada

The heatwave event to which the Ontario-Quebec area was subjected in 2018 resulted in significant morbidity and mortality. In this study, an investigation was conducted on how this heatwave affected the respective urban heat islands (UHIs) in Montreal and Ottawa. The modelled urban climates were compared before, during and after the heatwave using a Weather Research and Forecast (WRF) model having a 1 km spatial resolution. The UHI was calculated using two methods. As a first method, the “rural-ring” method was used to calculate the UHI in regard to temperature differences between urban and surrounding rural areas. The second method used the “urban-increment” approach where simulation results were compared to another simulation in which urban cells are replaced by croplands. Results show that urban land can raise temperatures by up to 12 °C at surfaces and 6 °C in the near-surface air. A synoptic anticyclone in the lower atmosphere was responsible for the heatwave, although both cities were located in areas peripheral to the anticyclone. During the heatwave, precipitation at the initial stage of the event and low wind conditions largely varied the pattern of the UHI effect within each urban center. The UHI was generally unchanged or even reduced during this heatwave, but there was substantial diurnal variation. Around noon and in the afternoon, the UHI was amplified by up to 3 °C, whereas it was suppressed or even negative at sunrise.

Hygrothermal simulation tools are commonly used to assess the moisture performance of building envelope components. Owing to the computational costs required to complete simulations over the long-term, one approach to reduce simulation time when undertaking hygrothermal design analysis is to select representative year(s) amongst sets of long-term climate data. To properly select these moisture reference year(s), a method is required to predict moisture performance and rank the climate years in terms of their moisture severity. To this end, several methods have been proposed in the literature, amongst which is the damage function method as reported in ASHRAE Project Report RP-1325. In this method, a stepwise regression model was developed to predict the damage function, as characterized by the RHT-index (integral of (Temperature - 0) (Relative Humidity – 70%)), in an OSB layer of a wood-framed wall as a function of several average yearly climate parameters for a North facing wall. The model was calibrated using climate and simulation data for eight cities in the USA and validated for three cities in the USA and one city in Canada (Winnipeg, MB). The method was found to be the most consistent and accurate amongst all ranking methods that have been evaluated. The objective of this paper was to: (1) evaluate the ASHRAE’s method for several Canadian locations; (2) determine whether the original model can be recalibrated in the event it is shown to be deficient; and (3) explore the potential of improving the model using other approaches such as the Partial Least Squares Regression (PLSR), the Least Absolute Shrinkage and Selection Operator (LASSO) regression, and the combination of LASSO feature selection and Support Vector Regression (SVR). The results suggest that for some Canadian locations, as were investigated in this study, the use of the original model may not be appropriate for predicting the moisture performance and ranking of climate years in terms of their moisture severity. However, the model was shown to perform better after it was recalibrated for Canadian locations but without improvement in ranking performance. Furthermore, the damage function model can be improved by using either PLSR, LASSO or SVR in terms of prediction and ranking.

Climate change will continue to bring about unprecedented climate extremes in the future, and buildings and infrastructure will be exposed to such conditions. To ensure that new and existing buildings deliver satisfactory performance over their design lives, their performance under current and future projected climates needs to be assessed by undertaking building simulations. This study prepares climate data needed for building simulations for 564 locations by bias-correcting the Canadian Regional Climate Model version 4 (CanRCM4) large ensemble (LE) simulations with reference to observations. Technical validation results show that bias-correction effectively reduces the bias associated with CanRCM4-LE simulations in terms of their marginal distributions and the inter-relationship between climate variables. To ensure that the range of projected climate change impacts are encompassed within these data sets, and to furthermore provide building moisture and energy reference years, the reference year files were prepared from bias-corrected CanRCM4-LE simulations and are comprised of a typical meteorological year for building energy applications, a typical and extreme moisture reference year, a typical downscaled year, an extreme warm year, and an extreme cold year.

Heritage buildings play a significant role in the Canadian government building stock; it is estimated that there are 1272 recognized federal heritage designated buildings in Canada, with 280 of these being classified as Federal Heritage Buildings. The majority of these heritage buildings are unlikely to have a building envelope which meets the thermal requirements of modern construction codes. The Government of Canada, through the Greening Government Strategy, has introduced increasingly ambitious greenhouse gas (GHG) emissions reduction targets for its real property portfolio. Introduced in 2017 and updated in 2020, the Greening Government Strategy commits the Government of Canada to reducing GHG emissions by 40% below 2005 levels by 2025, and by at least 90% below 2005 levels by 2050 (Government of Canada, 2021). Departments are expected to ensure that all major building retrofits, including heritage rehabilitation projects, prioritize GHG emission reduction and resiliency to climate change. For heritage buildings where the unique architectural features of the façade are to be conserved, achieving these ambitious GHG reduction requirements, as well as meeting modern thermal comfort requirements for building occupants, typically implies that insulation is required to be added to the interior of roofs, foundations and walls. However, it has been widely identified that for a heritage building, the addition of insulation on the interior of the building risks the exterior layers to be colder and wetter during the winter season. This can increase the risk to freeze thaw damage of heritage components in the envelope, thereby potentially risking the long term durability to heritage defining characteristics of the building.

Cross Laminated Timber (CLT) is increasingly used as structural component in low and mid-rise buildings. It comes with excellent carbon storage and prefabrication potential, and provides an interesting alternative for traditional construction methods. However, as it consists of wooden components, these panels are prone to degradation and delamination if exposed to long-term moisture sources, typically originating from on-site exposure to rain spells during the construction period. This study investigates different drying strategies by analyzing the wetting and drying processes by means of HAM-simulations for a CLT floor in a case-study with moisture-related degradation problems. Bore samples were taken from the CLT balcony where the most severe deterioration was observed, caused by insufficient rain protection during construction. After a rainy winter period the CLT was prematurely sealed off with an unventilated ETICS system (EPS + silicone plaster). In the analyses, it is seen that an unventilated finishing system results in a critical deterioration of the timber. The simulations show this could have been prevented by either choosing a ventilated finishing system or by sufficient rain protection during construction. In order to compare simulations with measurements, it is important to adopt a clear methodological approach for the hygrothermal simulations. Hence, a framework was developed that elaborates on each step of the development process of HAM-simulations, by means of a strategic three level selection system for model parameters. This approach allows to increase the usability and reliability of HAM-simulation in practice. At the end of the stepwise framework, the hygrothermal response from simulations was compared with the visual and experimental assessment of the wood samples. The study highlights the potential of HAM-simulations in both design as litigation context, and it was concluded that practice would benefit from a stepwise framework to conduct HAM-simulations, that provides guidelines to select climate, materials and performance criteria.

In the last decades, considerable work has been done regarding service life prediction of buildings and building components. Academics and members of the CIB W080 commission, as well as of ISO TC 59/SC14, have made several efforts in this area and created a general terminology for the concept of service life, which is extremely relevant for property management, life cycle assessment (LCA) and life cycle costs (LCC) analyses. Various definitions can be found in the literature that share common ideas. In fact, there are different criteria that trigger the end of a building’s service life, but the trap that building practitioners too often fall into and that should be avoided is dividing a problem into separate boxes, labels, and specializations without the mutual cohesion and interaction, and ignoring human behavior. Some definitions of service life are discussed in this review paper, in which the cause-effect processes underlying aging and decay are described. These descriptions highlight the continuous interrelation between different criteria for the end of a building’s service life, considering too often neglected and misunderstood causes of the end of life.

Parts of the building envelope that frequently receive high amounts of rain are usually exposed to a higher risk of deterioration due to moisture. Determination of such locations can thus help with the assessment of moisture-induced damage risks. This study performs computational fluid dynamics (CFD) simulations of wind-driven rain (WDR) on the Parliament buildings in Ottawa, Canada. Long-term time-varying wetting load due to WDR and potential evaporation are considered according to several years of meteorological data, and this cumulative assessment is proposed as a fast method to identify critical locations and periods. The results show that, on the Center Block of the Parliament buildings, the façades of lower towers facing east are the most exposed to WDR, together with the corners of the main tower. Periods of high WDR wetting load larger than the potential evaporation are observed, indicating that deposited rain may lead to moisture accumulation in the envelope. During these critical periods of up to several months, air temperature may repeatedly drop below freezing point, which poses a risk of freeze–thaw damage. First assessment on future freeze–thaw damage risks indicates an increase in such risks at moderate increases in temperature, but a lower risk is found for larger increases in temperature., Buildings, 11 (10), ISSN:2075-5309

The indoor environmental conditions (temperature and relative humidity) are critical when estimating the hygrothermal performance of building envelopes. Measured data is not always available and as such they are estimated using any of the various model available in the literature. The objective of this work was to compare the influence of indoor conditions calculation methods on the hygrothermal responses and the moisture performance of wood-frame wall assemblies in different Canadian cities (Ottawa, Vancouver and Calgary) under historical climate loads. Various combinations of controlled and uncontrolled indoor temperature and relative humidity were calculated using approaches proposed in the ASHRAE Standard 160. These indoor conditions were implemented as indoor boundary conditions in the simulation of heat and moisture transfer for four different types of wood-frame wall assemblies, assuming no leakage in the vapour barrier. These wall assemblies differ by their cladding types: fiberboard, vinyl, stucco and brick. In each city, simulations were run for two years as selected from a historical climate data set based on the moisture index. The wall orientation receiving the most wind-driven rain for the second year was selected for simulations in each city. A 2-storey residential building having 7 m height above grade, located in suburban area, was considered. The amount of wind-driven rain impinging on the surface of the walls was calculated using the model developed by Straube and Burnett (2000). Material properties were taken from the NRC material property database. Water infiltration through the assembly was assumed to be 1% of the wind-driven rain as suggested by the ASHRAE Standard 160. Temperature and relative humidity of the outer and inner surfaces of OSB sheathing and gypsum board were compared amongst the indoor conditions scenarios. The mould growth risk on the same surfaces was used to compare the influence of different indoor conditions scenarios on the moisture performance of the walls. The indoor temperature profiles calculated for the case where only heating is present fluctuate between 21°C and up to 30°C, depending on the outdoor temperature. With air conditioning, the indoor temperature varies between 21 and 24°C. For the indoor relative humidity profiles, when uncontrolled (no dehumidifier), it can fluctuate between 30 and 70%. With dehumidifier, the indoor relative humidity is either constant or varies within a limited range (45 to 56% in Ottawa, 44 to 52% in Vancouver, and 35 to 41% in Calgary). During the winter and summer periods, the difference between the controlled and uncontrolled relative humidity can be more than 25%. Temperature and relative humidity on the surfaces of the gypsum board reflected that of the indoor conditions. For all the cases analyzed, the indoor conditions did not have any significant impact on the temperature and relative humidity profiles of the OSB, and consequently the mould growth risk did not differ among the different indoor conditions for all cladding analyzed in all cities. When there is no leakage in the vapour barrier, the difference in indoor conditions is reflected mainly on the gypsum panel and hardly reach the OSB panel. Future studies should consider the air leakage as the exfiltration of warm and humid indoor air during the heating season may lead to the condensation in the structure that modifies the hygrothermal response of wall components.

Les bâtiments, les ponts, les routes, le transport en commun sur rail de même que les réseaux d'alimentation en eau potable et d'évacuation des eaux usées du Canada fournissent un abri et de l'eau potable, et permettent le transport des personnes et des marchandises ainsi que la collecte et le traitement des eaux usées. Ils fournissent des services de base essentiels aux Canadiens et sont d'une importance cruciale pour l'économie canadienne et la qualité de vie de la nation. Ces bâtiments et infrastructures publiques de base (BIPB) subissent des effets incertains et variables dans le temps en raison des changements climatiques, et sont soumis à des événements météorologiques extrêmes plus fréquents, comme les inondations. Ces pressions induites par les changements climatiques pourraient éventuellement réduire la sécurité, le rendement en service, la fonctionnalité et la durée de vie des BIPB du Canada. De plus, les BIPB canadiens vieillissent et se détériorent en raison de différents mécanismes de dégradation, ainsi que de pratiques inadéquates d'inspection et d'entretien – des problèmes potentiellement aggravés par les effets des changements climatiques. L'initiative Bâtiments et infrastructures publiques de base résilients aux changements climatiques (BIPBRCC) a été établie sous forme de partenariat de recherche-développement entre le Conseil national de recherches du Canada (CNRC) et Infrastructure Canada afin d'élaborer des codes, des normes, des spécifications, des lignes directrices et des outils décisionnels nouveaux et révisés pour rendre les BIPB nouveaux et existants au Canada plus résilients face aux effets des changements climatiques et des événements météorologiques extrêmes. Financée par Infrastructure Canada et gérée par le CNRC, cette initiative réunit des experts de partout au pays. Les secteurs prioritaires de l'initiative comprennent les bâtiments, les ponts, les routes, les réseaux d'eau potable, d'eaux pluviales et d'eaux usées, ainsi que les transports en commun sur rail. L'initiative porte sur la résilience face aux impacts des changements climatiques sur la température, les précipitations, le vent et les événements météorologiques extrêmes, notamment les inondations, les incendies de forêt et le vent extrême, qui peuvent affecter ces types de BIPB partout au pays.

Canada’s buildings, bridges, roads, rail transit, potable water systems and wastewater systems provide shelter and safe drinking water, enable transport of people and goods, and collect and treat wastewater. They provide basic and core services for Canadians and are critical to Canada’s economy and the nation’s quality of life. These buildings and core public infrastructure (B&CPI) are subject to time-varying and uncertain effects due to climate change, as well as more frequent extreme weather events, such as flooding. These climate changeinduced pressures could potentially reduce the safety, serviceability, functionality, and service life of Canada’s B&CPI. In addition, Canadian B&CPI are aging and deteriorating due to different degradation mechanisms, as well as inadequate inspection and maintenance practices – issues potentially made worse by the effects of climate change. The Climate-Resilient Buildings and Core Public Infrastructure (CRBCPI) initiative was established as a research and development partnership between the National Research Council of Canada (NRC) and Infrastructure Canada to develop new and revised codes, standards, specifications, guidelines and decision support tools to ensure that Canada’s new and existing B&CPI are more resilient to the effects of climate change and extreme weather events. Funded by Infrastructure Canada and managed by NRC, the effort brings together experts from across Canada. Initiative priority areas include buildings, bridges, roads, potable water, storm water, and wastewater systems, and rail transit guideways. The initiative addresses resilience to climate change impacts on temperature, precipitation, wind and extreme weather events, including flooding, wildfires and extreme wind, which can affect these types of B&CPI across the country.