Conference Agenda

Indoor environmental quality (IEQ) significantly impacts health, well-being, and comfort; yet research on residential IEQ, particularly in social housing, remains limited. Vulnerable populations in social housing can face heightened risks from poor IEQ. IEQ includes four main categories: thermal comfort, air quality, acoustic comfort, and visual comfort. This paper presents preliminary results from an exploratory field study assessing IEQ in social housing, focusing on the winter monitoring period and participant interviews. Thermal comfort, assessed using the ASHRAE Predicted Mean Vote model, was high, with participants experiencing comfortable conditions over 96% of the time. CO2 and PM2.5 concentrations remained within the acceptable range for over 90% of the monitoring period in most units. TVOC levels varied, with only three of the nine participants maintaining concentrations within the acceptable range for more than 80% of the time. Visual comfort was influenced by lighting distribution, colour temperature and daylight levels, while acoustic comfort was linked to building location. These findings contribute to a broader effort to understand and enhance IEQ in social housing.

To evaluate the actual performance of energy recovery ventilators (ERVs), it is important to consider the effects of air flow rate and air flow ratio of supply airflow rate to return airflow rate of ERVs, as well as unit exhaust air transfer ratio (UEATR) as a product test result. This paper consists of three parts. Firstly, we carried out airflow test, tracer gas test, thermal performance test on three products (Samples A, B and C) of ERVs according to ISO16494-1:2022. Experimental results confirmed that the smaller the supply and exhaust airflow rate, the greater the total (sensible plus latent) efficiency of ERVs. It was confirmed that the smaller the airflow ratio, the greater the total efficiency of ERVs. Secondly, a program for predicting the total efficiency of ERVs from the airflow rate, airflow ratio, and UEATR was developed. The total, sensible and latent efficiencies calculated by the program were compared with the above-mentioned test results and validated. Thirdly, as a factor to increase the airflow ratio of ERVs in buildings and to reduce actual energy efficiency of ERVs, the influence of exhaust-only mechanical ventilation such as in lavatories and machine rooms and consequent reduction of return airflow rate to the ERVs is picked up, and design solutions for the factor were examined from the viewpoint of energy uses for different components including heat sources. A solution, that is, locating air exhaust from the ERVs at halls adjacent to the lavatories and machine rooms was discussed, and the reduction of energy use of the HVAC systems thanks to the solution was quantified by using the energy calculation program incorporated with the above-mentioned program.

Quantifying airtightness is vital for achieving energy-efficient buildings and adequate indoor environmental quality, in particular for heritage buildings. This study is based on an existing database that includes airtightness measurements across a range of residential, commercial, and institutional buildings in Manitoba and aims to find a link between building type and airtightness quantification. Data from 62 airtightness tests was analyzed to draw conclusions on the general airtightness of heritage buildings. To analyze the data, assumptions were made to standardize interpretation, including defining test types (operational vs. envelope tests), external boundary conditions, retrofits, and pressurization values. All tests were conducted via blower door assessments in accordance with industry standards. However, limitations affecting data consistency were noted, including variability in testing crews, equipment calibration, and lack of environmental control over wind, temperature, and pressure conditions. Based on our analysis, a lack of trends between absolute leakage rates and normalized leakage rates was identified. The leakage levels varied from exceptionally airtight (0.4 L/s/m2) to excessively leaky (3.0 L/s/m2). It is recommended to use NLR75 when setting benchmarks as it provides less variation compared to ACH50. This consistency in NLR75 values, as noted through the clustering of data points in NLR75 vs. V/A figures, suggests it offers a more reliable and stable measure for assessing building airtightness. In contrast, ACH50 exhibited greater variability, which can complicate the benchmarking process and may lead to less accurate evaluations of a building's performance. Using NLR75 as a benchmark allows for more precise and consistent assessments, facilitating better comparisons and improvements in building airtightness.

Residential buildings in hot arid climates face acute challenges in achieving thermal comfort while minimizing energy consumption. This study introduces an AI-enhanced kinetic shading system that dynamically adapts to environmental conditions in real-time, optimizing shading and ventilation for maximum efficiency. Using machine learning models trained on meteorological and simulation-generated data, the system predicts ideal configurations to reduce cooling energy demand and enhance indoor comfort. Pilot simulations and comparative analyses reveal a 25%-35% reduction in energy consumption, a 3°C-6°C decrease in indoor temperatures, and improved daylight penetration and glare control compared to traditional static shading systems. This research bridges the gap between theory and practice by incorporating real-world testing, cost-benefit analyses, and user behavior studies to validate the system's feasibility. Future work will expand the system's applicability to diverse climates and building types while refining AI algorithms for greater adaptability. This study positions AI-driven shading systems as transformative tools for sustainable architecture, aligning with global energy efficiency and climate-resilience goals.

Each year, billions of dollars are spent constructing or renovating residential kitchens around the world. Very few dollars are spent investigating how well actually they work. In the emerging economies of the Asian-Pacific (APAC) region, literally millions of new residential kitchens are being constructed each year. Interestingly, despite the region’s cultural diversity, the universal drive to maximise real estate returns is resulting in a common urban domestic typology: the open plan kitchen. More interestingly, little is understood about how this layout performs, particularly in terms of ventilation and indoor air quality (IAQ), despite household air pollutants (HAP) being cited as a primary threat to health almost every country in this region { Health Effects Institute. 2024. State of Global Air 2024. Special Report.}.

Do the contemporary residential kitchen designs, prevalent in new construction in APAC lower-middle income countries (LMIC), reduce or exacerbate HAP? How can this be best assessed, recognising (1) differences in occupant behaviour, (2) differences in indoor sources of pollutants, and (3) differences in outdoor environmental conditions (pollution and weather) have significant impacts on IAQ? And how can real as-built kitchen designs, normal kitchen use, indoor air quality and ventilation be evaluated when most people are reluctant to let strangers carrying wired gadgets intrude into their inner sanctums of domesticity.

This paper outlines an affordable and accessible methodology for a post-occupancy evaluation (POE) study: one that combines a short behaviour survey, smartphone LiDAR and photogrammetry technology, low-cost sensors and two common household staples. This methodology will be used to assess how well new urban kitchens in ten rapidly urbanising Asian LMIC cities is performing across the three primary socio-economic groups.

Portable air cleaners (PACs) are simple appliances that can be used to reduce indoor concentrations of fine particulate matter (PM2.5). However, PAC performance, measured by absolute and relative reductions in PM2.5 concentration, can vary considerably in real environments. To understand the extent that performance is influenced by user behaviour, a three-arm randomized crossover trial testing PACs was conducted in 60 apartments in three neighbouring buildings in Toronto, Canada. PACs operated under one of three conditions (placebo, constant filtration, and automated) for each one-week study arm. Particulate matter (PM) concentrations were measured continuously using PurpleAir sensors. Weekly surveys were used to estimate the frequency of specific behaviours that may affect PM2.5 concentrations during each study arm. Larger absolute reductions were consistently observed in homes with relatively high indoor PM2.5 concentrations during the placebo arm. Relative reductions were less consistent, although frequently greater in homes with lower average concentrations. Similar results were observed during the automation arm. The variation in PM2.5 concentrations within and between homes can be attributed to at least three of the behavioural factors evaluated by the survey: smoking; use of incense, candles, and essential oil diffusers; and opening the balcony door. Future intervention studies should therefore make efforts to track these and other behavioural factors, as well as environmental factors that can affect indoor PM2.5 concentrations, as these may provide context for evaluating PAC performance as well as information that may be helpful in any assessment of health outcomes.

Indoor Environmental Quality contains three elements that can no longer be ignored. First, it is not an expansion of Indoor Air Quality as many assume. IEQ contains IAQ as one of four factors. Second, IEQ is not just a grouping of factors and measurements. IEQ includes the interactions among and between the factors, characteristics, and measurements of buildings. Third, by definition, the occupants are part of the indoor environment. The expansion beyond IAQ creates a rich but complex challenge for those who explore, measure, recommend, maintain, and are otherwise involved in the health and wellness of buildings. ASHRAE Guideline 10-2023 and Addendum a (2024) directly address those complexities. The title provides the description and the purpose as, Interactions Involving the Achievement of Acceptable Indoor Environments. Guideline 10 identifies the four factors (Thermal, IAQ, Lighting, and Sound) and cross references the interactions in Table 3. Implementation, however, is beyond the scope of Guideline 10. There is a published example of an application that includes IEQ, interactions, and occupants: Environmental house calls can reduce symptoms of chemical intolerance: a demonstration of personalized exposure medicine. (Primary health care research & development. 25. e53. 10.1017/S146342362400046X.) The study interviewed 37 residential occupants, identified levels of intolerance of each to common household chemicals, conducted an inventory of exposure sources, collected environmental samples which were analyzed by an accredited lab. The subjective QEESI Symptom Star registered occupant perception of their environment. The occupants were then given verbal and written guidance on exposure sources and how to reduce exposures themselves. Follow-up included observations of source removal, retesting the environment, and administering the QEESI Symptom Star of impact on the occupant. The results showed that education was effective for changes, and those changes were measurable both by environmental sampling and occupant response.

This study develops a holistic model for assessing indoor environmental quality (IEQ) and energy utility quality (EUQ) in multifamily apartment units located in Baton Rouge, Louisiana. The research introduces the Sustainable Indoor Environmental Quality (IEQs) model with a similar dimension, which incorporates EUQ to address the interplay between energy efficiency and occupant comfort. Field measurements were conducted to evaluate thermal comfort, air quality, lighting, and acoustics. The male apartment unit achieved an objective IEQ (IEQo) score of 59.0%, while the female unit scored 62.5%, primarily due to differences in lighting and air quality performance. Additionally, the female unit exhibited higher monthly Energy Use Intensity (EUI) across seasons compared to the male unit, with a higher average monthly EUI in the heating season compared to the cooling season, impacting the EUQ score (40%) and, consequently, the IEQs score. The stringent dimension of IEQs was important to establish the validity of the proposed model. While the investigated buildings demonstrate some degree of climate resilience, the findings underscore the importance of integrating energy performance with IEQ assessments, offering a comprehensive framework for building evaluation.

In facilities where temperature, pressure, and air quality control are critical, detecting and sealing air leakage in interior walls is as critical as in exterior walls. Infrared thermography (IRT), especially when combined with forced depressurization, is commonly used to visualize leakage by capturing surface temperature changes caused by air inflow. However, it is typically more effective for exterior walls, where a sufficient temperature difference exists between indoors and outdoors. This study proposes an interior wall leakage detection method using IRT combined with depressurization and forced indoor cooling to enhance detection and quantification. Application experiments were conducted in an aged room with six suspected leakage paths. IRT images were captured under four conditions: (1) natural condition, (2) depressurization only, (3) forced cooling only, and (4) forced cooling with depressurization. Complex leakage patterns in interior walls were detected using a threshold method based on the minimum, maximum, and average temperatures of each image, with leakage areas identified through temperature contrast with adjacent regions. Enhanced visibility of suspected leakage areas was observed in the binary images when the interior surface was cooled and depressurized simultaneously, and a comparison with the typical blower-door test revealed that this condition produced relatively similar ranking results across the evaluation targets.

Ensuring clean air in densely populated environments, such as trains, is important for occupant health. To achieve this, filtration systems should be rigorously tested under both standardized and real-world conditions to comprehensively validate their performance. This study evaluated the filtration efficacy of two filters; a standard E10 filter and a MERV 13 filter with a proprietary coating. Two distinct testing configurations were established in an accredited laboratory facility to provide a comprehensive evaluation of performance using microbial challenges.

In a single-pass test configuration aligned with ISO 15714 standards, the filters were assessed for immediate filtration performance against a microbial challenge containing Influenza A virus and Staphylococcus epidermidis (S. epi). Results showed that the proprietary-coated MERV 13 filter achieved reductions of 83.02% for S. epi and 95.10% for Influenza A, while the standard E10 filter demonstrated reductions of 96.91% for S. epi and 96.84% for Influenza A.

A bespoke closed-loop setup simulating a train's HVAC system was used to evaluate prolonged filtration performance against S. epi. Over 60 minutes, the proprietary-coated MERV 13 filter achieved a 98.22% reduction in S. epi concentration, outperforming the standard E10 filter, which achieved a 95.2% reduction.

The results underscore the importance of employing both standardized and real-world testing scenarios to assess the performance of filtration products and support informed decision making. The proprietary coating enhanced the MERV 13 filter’s long-term efficacy while maintaining competitive single-pass filtration performance. These findings highlight the value of bespoke testing setups tailored to real-world conditions to ensure reliable and effective solutions for healthier indoor environments.

A floor heating system offers a highly comfortable living environment by providing an optimal temperature distribution keeping the air cooler around the head while maintaining warmth at the feet. Previous studies on thermal comfort suggest that the floor heating system enables direct warmth through thermal radiation, which can lead to discomfort when used for long-term. Therefore, it is necessary to evaluate the thermal sensation of floor heating system with focusing the thermal sensation and energy consumption on time dependence. In this study, with using the composition of floor materials and underfloor materials for floor heating system, the long-term measurements focusing on the relationship between thermal properties and power consumption, and the subject experiments on thermal sensation evaluation was performed. The tatami and wooden flooring were used in this experiment. We will report that the relationship between the psychological evaluation of thermal sensation, comfort, etc. of 10 subjects and the thermal properties of floor heating, such as power consumption, surface temperature, and contact temperature, when the composition of floor materials and underfloor materials was rearranged in the traditional Japanese lifestyle of sitting on the floor. As a result, although the surface temperature of tatami is about 2 to 2.5 K lower than that of wooden flooring, it leads to energy savings of about 5 to 10%. At this time, there was no difference in the contact temperature of the buttocks in contact with the flooring material, and the thermal sensation tended to be higher with tatami, revealing differences in thermal sensation and energy saving due to the different constituent materials.

Office space is the place where the employees spend most of their day, and it is known that the office environment affects their psychology and physiology. It has been pointed out that various factors in offices, such as noise, indoor air quality, lighting, and seating position, exert stress on employees, causing them to work less efficiently and to leave their jobs. As a countermeasure, for example, in 2014, Delos Corporation began operating the WELL Building Standard certification system, as a workspace evaluation system for office. In this certification, the office environments are considered as a big factor that affects the mental and physical health of employees. Among these environments, the importance of planting has been attracting attention, and it can be said that the effects of planting in offices on the psychology and physiology of employees will be considered important. Previous studies have shown that indoor planting offers air purification and visual healing effects, contributing to the reduction of employees' stress. Therefore, number of companies are incorporating planting in their offices in consideration of the impact of the office environment on employee psychology and physiology. Although there are several studies on planting arrangements in office spaces, only few have evaluated the effects of their layout conditions on office workers' impressions. In this study, the relationship between the arrangement of plantings in office space and the subjects' sensation were examined using Sandplay therapy. The outcome of this study can contribute to the proposal for an effective arrangement of plantings for reducing employees' stress and for efficient work when indoor greening is implemented in office spaces.