Residential Housing Research Articles

Flood Risk Assessment and Its Implications on Critical Infrastructure Resilience in Nigeria

Flooding is one of the recurrent natural disasters in Nigeria that poses huge threats to not just people but also critical infrastructures. In 2024, the Federal Ministry of Water Resources and Sanitation and the Nigeria Hydrological Services Agency (NIHSA) identified 31 states including the FCT as high-risk areas for significant flood impacts. The impact of floods generally has caused devastating damage to critical infrastructures resulting from high rain intensities for a long duration. It becomes pertinent to evaluate the impact of floods on critical infrastructures like roads, bridges, residential buildings, water supply systems, and electricity facilities. Thus, this research seeks to explore the vulnerabilities and impacts of floods on critical infrastructure which is fundamental to economic growth, development, and coping mechanisms. A structured questionnaire was distributed among a sample of 90 including government department, construction industry, and community members to seek their views on the vulnerability risk of infrastructure and flood sources. Results indicate that most of the damages reported 42% were due to the destruction of roads and bridges, followed by residential houses at 31%. The main cause of flooding identified by 54% of respondents was poor drainage systems, while 31% cited poor waste management as a contributing issue. Hence, restoration of the drainage systems, implementation of prohibitions on encroachment of flood-prone areas and improvement of early warning systems are critical and pressing. The uniqueness of the study lies in its effort to address the gaps and challenges that exist in infrastructure resilience by identifying the most critical elements that are prone to risks and proposing mitigation measures against floods in the urban centers of Nigeria which are experiencing rapid growth.

Open-Source Software for Building-Integrated Photovoltaic Tiling for Novelty Architecture

Novelty architecture buildings can be tiled with conventional rectangular solar photovoltaic (PV) modules with both close-packed cells or partially transparent modules, vastly increasing renewable energy, reducing carbon emissions, and allowing for positive energy buildings. To enable this potential, in this study, for the first time, two open-source programs were developed and integrated to provide a foundation for designing and coating real-life novelty architecture buildings and objects with solar PV modules. First, a tiling algorithm was proposed and integrated into Blender that can generate solar PV modules on the face of any 3D model, and an augmented Python version of SAM was developed to simulate the performance of the resultant irregularly shaped PV systems. The integrated open-source software was used to analyze the energy performance of seven different novelty BIPVs located across the globe. The buildings’ energy performance was compared to conventional ground-based PV systems, and the results showed that the conventional arrays generate more energy per unit power than the BIPVs. The analysis reveals that the more complex the building model geometry, the less energy the building generates; however, the novelty BIPV power and energy densities far surpass conventional ground-based PV. The real estate savings observed were substantial, reaching 170% in one case where the BIPV reached 750 m in height. The BIPVs’ energy production is optimized by orienting the building via rotation and only needs to be carried out a single time for replication anywhere globally. The results show that the energy yield of the BIPV increases as the building becomes more detailed while the total power and energy decrease, indicating the need for the careful balancing of priorities in building design. Finally, the energy simulations demonstrate the potential for net-positive energy buildings and contribute to net-zero-emission cities. The findings indicate that BIPVs are not only appropriate for conventional residential houses and commercial buildings, but also for historical building replicas or monuments in the future. Further studies are needed to investigate the structural, electrical, and socio-economic aspects of novelty-architecture BIPVs.

Determinants of Soundscape Quality of Communal Open Space in Hong Kong

Soundscape quality of communal open space (COS) in residential housing estates has been less thoroughly investigated. This paper aims to reveal the intricate relationships among physical sound, visual and thermal environments and their respective human perceptions, and soundscape quality, as well as their relative influences. To this end, a path model was formulated with aid of 1749 face-to-face field interview responses collected via questionnaire surveys together with physical measurements at the COS of nine residential housing estates in Hong Kong. The model findings suggested that pleasantness and landscape visual quality, as well as thermal acceptability were the primary drivers for soundscape quality of COS. The size of effects of thermal perceptions on soundscape quality was found comparable to those of aural and visual perceptions. In turn, pleasantness was more influenced by perception of dominant vehicle sound, human sound and birdsong than physical sound properties and psychoacoustics factors. Visual quality of landscape also played an important role on soundscape assessments via visibility of greenery and sky. Besides, thermal acceptability was found to directly influence soundscape assessments instead of thermal comfort or sensation. Above all, our findings provide valuable insights for residential housing estate designers in formulating strategies that can effectively improve soundscape quality in COS in compact city environments.

Unveiling the prediction model and mechanism of the collapse of bank slope in the lancangjiang area

This study takes the bank collapse at the left bank of Badi Township of the Lidi Hydropower Station in the Lancang Area as an example. To address the lack of in-depth research on the prediction model and mechanisms of bank collapse, this study conducts field drilling surveys, investigates influencing factors, analyzes causal mechanisms, and proposes prediction methods based on the geological survey data of bank collapse in the reservoir area. The study explores the stratigraphic lithology, determines the key parameters for bank collapse prediction, and studies the failure modes and bank collapse mechanisms. It also proposes the finite element method of bank collapse to predict the width and elevation of bank collapse and provides the influence on the surrounding environment. The results show that the collapsed bank on the left bank of Badi Township is a high and steep soil-like slope, and forms the collapse and retreat type of failure mode after impoundment. The Kachukin method, the bank slope structure method, and the proposed finite element method are used to predict the width and elevation of the collapsed bank. The results indicate that the Kachujin method predicts a larger range of bank collapses and is biased towards safety. In contrast, the prediction ranges of the bank slope structure method and the finite element method are close. The bank collapse position is located in the middle and rear of the residential houses in Badi Township, which is consistent with the on-site investigation and has strong reliability. The predicted width of the bank collapse is about 34 m and the elevation is about 1,845 m. The research results can be directly applied to preventing and controlling bank collapse and have powerful practical application value.

Evaluating Indoor Air Quality in Residential Environments: A Study of PM2.5 and CO2 Dynamics Using Low-Cost Sensors

Indoor air quality (IAQ) poses a significant public health concern, and exposures to high levels of fine particulate matter (PM2.5) and carbon dioxide (CO2) could have detrimental health impacts. This study focused on assessing the indoor air pollutants in a residential house located in the town of Mission, Hidalgo County, South Texas, USA. The PM2.5 and CO2 were monitored indoors: the kitchen and the bedroom. This investigation also aimed to elucidate the effects of household activities such as cooking and human occupancy on these pollutants. Low-cost sensors (LCSs) from TSI AirAssure™ were used in this study. They were deployed within the breathing zone at approximately 1.5 m above the ground. Calibration of the low-cost sensors against Federal Equivalent Method (FEM) instruments was undertaken using a multiple linear regression method (MLR) model to improve the data accuracy. The indoor PM2.5 levels were significantly influenced by cooking activities, with the peak PM2.5 concentrations reaching up to 118.45 μg/m3. The CO2 levels in the bedroom increased during the occupant’s sleeping period, reaching as high as 1149.73 ppm. The health risk assessment was assessed through toxicity potential (TP) calculations for the PM2.5 concentrations. TP values of 0.21 and 0.20 were obtained in the kitchen and bedroom, respectively. The TP values were below the health hazard threshold (i.e., TP < 1). These low TP values could be attributed to the use of electric stoves and efficient ventilation systems. This research highlights the effectiveness of low-cost sensors for continuous IAQ monitoring and helps promote better awareness of and necessary interventions for salubrious indoor microenvironments.

Model Lanskap Permukiman Tradisional Masyarakat Adat Rejang Provinsi Bengkulu Berbasis Budaya Lokal

Rejang is one of the original tribes of Bengkulu Province. This tribe mostly lives in the Bukit Barisan area. Some of their settlements are undergoing changes due to the rapidly growing flow of information and communication today. Conservation efforts need to be made, especially about their traditional settlement landscape model. The purpose of this study is to identify and analyze the character of traditional settlement landscapes and their constituent elements and compile a model of traditional settlement landscapes of the indigenous Rejang people. This research uses a descriptive method through a literature study approach, interviews, and field observations. The analysis was carried out descriptively and spatially. The landscape character of the indigenous Rejang tribe settlement is in the form of hilly landforms with land cover in the form of forests, gardens, and terraced rice fields, with the valley floor in the form of small and medium rivers. Traditional settlements stretch over ridges to mountain peaks. The character-forming features of landscapes include both natural and artificial features. Natural features consist of the elements of hills, forests, and rivers. Artificial features consist of terraced rice fields, gardens/fields, and settlements. The settlement itself includes traditional houses (including traditional chiefs' houses), circulation paths, public open spaces, and tombs. The elements that make up the Residential Garden include residential houses, rice barns (tangkiang), kitchens, fence plants, vegetable and flower plants, trees, yards, mortar (places to pound rice). Traditional ceremonial activities are held inside and outside the home, as well as communal activities such as planting and harvesting rice held in rice fields. The landscape model of the traditional settlement of the indigenous people of Rejang Lebong is linear with the center of the settlement along the main road on the ridge. The settlement is surrounded by gardens/fields and rice fields. The forest is on the outside away from settlements.

Exploratory Analysis of a Novel Modular Green Wall’s Impact on Indoor Temperature and Energy Consumption in Residential Buildings: A Case Study from Belgium

One possible solution that mitigates the effects of climate change is the implementation of vertical greenery systems, which have the potential to reduce the need for cooling and provide energy savings for heating. This paper evaluates the effects of an innovative modular green wall on indoor temperature and energy use in a residential case study building. This research was carried out on a residential house in the city of Ghent, Belgium, whose southwest facade is covered with a specific type of modular green wall (a structure with a specific substrate and plants that have the ability to purify water so that it can be reused in the house). The monitoring process included four different temperatures (in front of and behind the green wall, in the substrate, and on the wall without greenery) during winter and summer periods. To analyze the effect on the internal temperature and energy use, a DesignBuilder simulation model was built and validated against these experimental results. This green wall has proven to have the greatest effect during the hottest summer days by reducing the indoor temperature by up to 3.5 °C. It also effectively increases the indoor temperature by up to 1.4 °C on a cold winter day, leading to energy savings of 6% on an annual basis.

Glacial lake outburst flood risk assessment of a rapidly expanding glacial lake in the Ladakh region of Western Himalaya, using hydrodynamic modeling

The ongoing trend of warming climate has made Glacial Lake Outburst Floods (GLOFs) a major cryospheric hazard worldwide, especially in the Himalayas. GLOFs in the Himalayan region are mostly caused by moraine-dammed proglacial lakes and ice-dammed lakes. These sporadic disasters have resulted in significant loss of life and property. This study offers a comprehensive analysis of the GLOF hazard potential of a potentially dangerous proglacial lake (PDGL) in the Ladakh region. This research explores the GLOF threat from the lake using multi-criteria analysis and advanced 2D hydrodynamic modeling approaches. The mass balance response of the mother glacier, its flow dynamics, and glacier-lake interactions were examined for the past 22 years. The findings show that over this period, the PDGL has had a notable expansion of 78.7%, accompanied by a significant recession of 13.2% in its feeding glacier. The glacier has witnessed an average thickness loss of ⁓7 m at the rate of 0.32 m a−1 during this period. The average, lowest, and maximum depth of the glacier were found to be 30.95, 14.30, and 50.57 m, respectively and the average velocity of the glacier was estimated as 3.38 m a−1. Because of the lake’s rapid expansion and steep surrounding slopes, it was classified as a high-hazard lake. The risk to the downstream community was assessed through 2D hydrodynamic modeling using the HEC-RAS tool. The maximum discharge under the worst-case scenario for the piping and overtopping failures was estimated as 3890.99 m3s−1 and 5111.39 m3s−1, respectively. The area potentially under the threat of inundation was calculated to be 4.74 and 5.38 km2 for the moderate and worst-case scenarios respectively. The expected maximum flood velocities range from 18.26 to 23.78 meters, respectively for the moderate and worst-case scenarios. At several locations in the downstream area, routed hydrographs representing the GLOF propagation were generated. The findings show that the flood wave in the worst-case scenario would arrive at the first settlement in 50 min, with a peak velocity of 12.36 m s−1. The potentially inundated area includes critical infrastructure such as bridges, residential houses, and roads. To mitigate the potential risk associated with this lake, a more detailed and on-site study is highly recommended.

Board assignment heuristics for nail laminated out-of-grade timber

ABSTRACT Structural sawn timber, sourced from softwood plantations, is widely used in lightweight timber-framed residential housing and in engineered wood products for contemporary mass timber construction. However, a significant proportion of milled timber boards are considered ‘out-of-grade’, failing to attain a structural grade under existing classifications systems due to various stiffness, strength, and/or utility-limiting features. This study investigates the potential of controlled lamination techniques to produce structurally usable laminated timber products from out-of-grade timber, using a minimal number of requisite boards. Numerical and experimental methods were employed to compare different board assignment heuristics, in terms of reducing the stiffness variability in laminated board populations. The results indicate that controlled board locations produced remarkably consistent laminated products, achieving very low variability even with a minimum lamination of only two boards. The findings of this paper suggest that controlled lamination techniques have the potential to transform low-value out-of-grade timber into a valuable resource for value-added applications, challenging the existing market perception that out-of-grade timber lacks structural usability.

Riverine macroplastic survey along the segments of Tullahan River in Metro Manila, Philippines

The Philippines is one of the world’s main contributors to global marine plastic pollution. However, field data remains scarce, so model estimates of riverine plastic pollution may be inaccurate. This paper aims to characterize the macrolitter observed along the Tullahan River, with focus on plastics, passing through the barangays of Quezon City and Valenzuela City in Metro Manila. The impact of solid waste management and land use activities on plastic flux were also investigated. For the floating litter, visual counting and float method were used to determine the plastic flux and river velocity, respectively. Riverbank litter was collected manually to characterize it based on plastic product and polymer type. Results show that the macroplastic flux was lowest on the site where residential houses are farthest from the stream. Waste characterization revealed that riverbank litter was primarily plastic – 30%–41% were residuals, and 5%–21% were recyclables. Both methods revealed that wrappers and thin PE plastics are the top contributors to riverine macroplastic pollution. Therefore, the entry of macroplastics into the river may be due to land use activities and weak enforcement of existing solid waste management (SWM) policies. The points discussed in the study can help in improving SWM and land use planning. The results can also increase the accuracy of model estimates.

Analysis Of the Impact of China's Population Age Structure on Residential Commercial Housing Prices

With the intensification of global aging, the impact of changes in population age structure on the real estate market is becoming increasingly significant. This article aims to explore the impact of changes in China's population age structure on the prices of residential commercial housing, to provide a scientific basis for regulating the real estate market. By analyzing data from 30 provinces and cities in China from 2013 to 2022, this article finds that as aging population intensifies and the number of children decreases, both the old-age dependency ratio and the child-age dependency ratio have a negative impact on housing prices. This means that the aging society and the economic pressure of childcare may weaken the demand for home purchases. Household Saving Rate and increase in total population positively drive house prices, while the relationship between per capita income and house prices is not significant. From a regional perspective, the aging population in the eastern region has a significant effect on suppressing housing prices, while the impact is gradually evident in the central region. The western region has a smaller impact and population growth suppresses housing price increases. The study emphasizes the impact of changes in the age structure of the Chinese population on the prices of residential properties and proposes policy recommendations such as improving old-age security and optimizing the housing supply structure to promote the steady development of the real estate market.

Validation of a Model Predictive Control Strategy on a High Fidelity Building Emulator

In recent years, advanced controllers, including Model Predictive Control (MPC), have emerged as promising solutions to improve the efficiency of building energy systems. This paper explores the capabilities of MPC in handling multiple control objectives and constraints. A first MPC controller focuses on the task of ensuring thermal comfort in a residential house served by a heat pump while minimizing the operating costs when subject to different pricing schedules. A second MPC controller working on the same system tests the ability of MPC to deal with demand response events by enforcing a time-varying maximum power usage limitation signal from the electric grid. Furthermore, multiple combinations of the control parameters are tested in order to assess their influence on the controller performance. The controllers are tested on the BOPTEST framework, which offers standardized test cases in high-fidelity emulation models, and pre-defined baseline control strategies to allow fair comparisons also across different studies. Results show that MPC is able to handle multi-objective optimal control problems, reducing thermal comfort violations by between 66.9% and 82% and operational costs between 15.8% up to 20.1%, depending on the specific scenario analyzed. Moreover, MPC proves its capability to exploit the building thermal mass to shift heating power consumption, allowing the latter to adapt its time profile to time-varying constraints. The proposed methodology is based on technologically feasible steps that are intended to be easily transferred to large scale, in-field applications.

Comparison of Indoor Climate between Wooden wall Construction and Concrete Wall Construction during Winter Season

Abstract This research aims to determine the importance of thermal comfort in buildings, especially residential houses, with a focus on two types of houses that have different structures as a comparison. The research also focuses on productive rooms that are frequently used every day, considering the long duration of use. Data collection methods include distributing questionnaires to residents, as well as a quantitative approach using experiments and thermal measurements of temperature and humidity in each room, including surface measurements to compare the two types of buildings. The analysis results show that there are differences in thermal comfort between the two types of houses. Houses with wooden construction show relative humidity that reaches a comfortable point (45-65%), while houses with concrete construction tend to move cold temperatures from outside to indoors more quickly. Although efforts have been made to achieve thermal comfort in every room, the main challenge remains related to the energy consumption of artificial comfort systems. The study location in Japan took into account the different outdoor temperature variations each season. The findings we got were that houses with wooden construction walls tend to be warmer due to several factors, one of which is that this building is an apartment type with openings that tend to be smaller compared to buildings with wooden construction walls which are a traditional Japanese house type with wide openings. The measurement results using PMV analysis for both buildings were measured at 2 times at the same time, namely during the day and at night. Measurements were carried out in the living room as a comparison room with the function of a room that has the same user interaction between the two buildings. Honjo Nishi Danci Apartment (concrete wall construction) has a comfort level in the quite comfortable category compared to the living room in the apartment. Kitakyushu Islamic Cultural Center (wooden wall construction). Data was taken when both buildings did not turn on the air conditioner so that the data taken could be comparable. At night, the conditions in the living room have a slightly warm sensation because the user uses air conditioning in the room because the user sleeps in this room. the conditions in the living room at the Islamic Cultural Center have a cold sensation due to the lack of activity and use of this room. So the sensation at night tends to be cold. These findings can guide building designers in developing architectural solutions that are sustainable and focused on indoor comfort in winter.

Assessment of harmful gases emission and its impact using IoT and geospatial technology

Numerous industries in our daily lives use a variety of dangerous chemical gases, and workers are frequently exposed to these gases. The losses due to harmful gases can be reduced by developing an automatic harmful gases detection and alerting system. This study aims to design, develop, and implement an automatic warning system using series of gas sensors to deduct. The designed system is implemented to monitor 3 locations to detect the hazardous pollutions parameters, namely Large-Scale industries, wood burning sites and residential housings and analysed to understand the pollution level. This study observed elevated temperatures (35–45 °C) and heat index (30–50 °C) in large-scale industries, along with higher harmful gases compared to wood-burning sites and homes. Interestingly, wood-burning sites exhibited higher humidity (60–70 %) and peak ozone and methane levels compared to other locations. These variations underscore the unique environmental characteristics of each site, emphasizing the need for tailored monitoring and safety measures.

Health impact assessment of exposure to road traffic noise and air pollution according to pre- and post-densification scenarios in Helsingborg, Sweden

A prevalent solution to accommodate population growth due to urbanization is densification. However, this often pushes new residential housing closer to roads, increasing exposure to both noise and air pollution. The present study’s aim was to estimate the health impacts of road traffic-related noise and air pollution for a low-income area (Drottninghög) in Helsingborg, Sweden, according to pre-densification (2012) and post-densification (2030) scenarios.Road traffic noise was simulated at the façade of residential buildings using the Nordic prediction method, and exposure was assessed using SoundPLAN. Exposure-response functions (ERF) from the WHO were utilized for the following health outcomes associated with noise: annoyance, adverse sleep disturbance, ischemic heart disease (IHD) incidence and IHD mortality. Air pollution (nitrogen dioxide, NO2) was assessed using a Gaussian dispersion model (AERMODE). Health outcomes associated with NO2 included natural cause mortality, pediatric asthma, respiratory hospitalizations and low birth weight (LBW). ERFs were derived from meta-analyses. Health impact assessments were then performed for both scenarios.Densifying Drottninghög according to the municipality’s planned strategy would lead to a 15 % unit increase in the proportion of residents exposed to road traffic noise above the WHO’s health-based guideline value (53 dB(A) Lden). This was estimated to markedly increase the proportion of residents highly annoyed by traffic noise (7.4–13.9 %) as well as those highly sleep disturbed (3.0–4.9 %). IHD incidence and IHD mortality attributed to noise would increase by an estimated 49 % and 44 %, respectively, post-densification. NO2 exposure was estimated to increase slightly (0.7 µg/m3) post-densification, which would contribute to an estimated 4–6 % increase in natural cause mortality, pediatric asthma, respiratory hospitalization and LBW.Urban planning initiatives need to consider these prevalent urban environmental exposures and integrate a public health perspective into densification strategies. Doing so can create synergies in the built environment that promote healthy, sustainable cities.

The Impact of Housing Market Regulation Policies on the Housing Choice Behavior of Urban Residents

Abstract Housing is a social and developmental issue of public concern, which is related to the personal interests of every household and the people’s “living in a home”. The article quantifies the housing choice behavior of urban residents by the ring index of residential housing purchase price, and solves the problem of sample selection error by using the propensity to match score to match the experimental group and the control group. A double difference model is used to analyze the net effect of the implementation of housing market regulation policies on urban residents’ housing choice behavior. Parallel trend test in the experimental and control groups before and after the implementation of housing market regulation policies in 2018 shows significant differences, the ATT value of HSB after propensity score matching is positive, and the sample mean of the control group is 0.452 lower than that of the experimental group. The coefficient of the effect of housing market regulation policies on the behavior of urban residents’ housing choices is 0.351 and shows significance at the 1% level. The active implementation of housing market regulation policy can help optimize the housing purchase price index, which in turn stimulates the housing choice behavior of urban residents and promotes the stable and healthy development of the housing market.

External Thermal Insulation Composite Systems—Past and Future in a Sustainable Urban Environment

In recent decades, the sustainable development of the planet has been negatively affected by a number of factors, including the construction industry. The construction industry includes, among other things, the highly topical energy reconstruction of existing prefabricated residential housing, which is implemented to improve their condition from a thermal engineering and energy perspective. Composite materials, known as external thermal insulation composite systems (ETICSs), have come to the fore, bringing a number of undeniable benefits to society. After more than 20 years of experience, it turns out that in addition to the benefits, ETICSs also bring new research challenges to the discussion, which are related to the issue of the biocorrosion of the external envelope of ETICSs, and also to the issue of the indoor microclimate. Based on the literature review and case studies, we aim to show that ecologically friendly building materials require a multidisciplinary approach. At the same time, we want to contribute to the discussion of whether the diversity of microorganisms on ETICS composites is a potential source of health risks and whether the transport of microorganisms to the indoor environment can be ruled out through natural ventilation from the outdoor environment to the interior.

Indoor environment and user perceptions in offices in Greenland compared to Denmark

Most of the Greenlandic building stock comprises residential houses and apartments. Consequently, the indoor environment in Greenlandic office buildings has not been subject to wide-ranging investigations. The purpose of this study was to investigate the indoor environment in office buildings in Greenland and to characterise the buildings, their indoor environment, and occupant well-being, health and self-assessed performance. This was done through a post occupancy evaluation (POE), where 22 office buildings, including 70 offices in Nuuk and Sisimiut, were evaluated based on indoor environment measurements and questionnaires of occupants' perceived indoor environment. This was compared with data and results from a related study in office buildings in Denmark (26 office buildings, including 83 offices) collected in the same period. The Danish office buildings performed slightly better than the Greenlandic office buildings regarding the perceived indoor environment. The measured indoor environment differed in performance between the countries when benchmarking towards the requirements and guidelines of the Danish Working Environment Authority (DWEA). It was concluded that the office buildings in Greenland did not differ much from the office buildings in Denmark regarding the measured and perceived indoor environment.

A Multivariate Model and Correlation Study on the Impact of Typical Residential Spatial Forms in the Middle Reaches of the Hanjiang River on the Thermal Environment and Thermal Comfort

Different spatial forms affect the indoor thermal environment and human thermal comfort. A good living environment largely depends on the flexibility of spatial forms, and spatial scale and proportion are the key factors affecting these forms. We selected typical residential houses in the middle reaches of the Hanjiang River in the hot summer and cold winter climate area as an example. Through on-site measurements and questionnaire surveys, we studied the impact of residential form indicators on the thermal environment and thermal comfort. We also established a multivariate model to explore the correlation among various parameters. The results showed that the spatial-real ratio of the residential spatial form index in the middle reaches of Hanjiang River was 5–58%. The height from the ground was 2.23–6.92 m. The open-space ratio was 0.04–4.55. The explanatory power of the spatial form index to indoor air temperature was 57.5%, with a strong correlation (R2 = 0.675). The explanatory power for humidity was 38.2%, with a weak correlation (R2 = 0.525). The explanatory power of SET was 30.6–50.1%, with a weak correlation (R2 = 0.466). The explanatory power of PMV was 6.5–31.7%, and PMV1.0 was weakly correlated (R2 = 0.474). The explanatory power for PPD was 15.5%, where PPD 1.0 was close to a weak correlation (R2 = 0.508). The results of this study provide reference values for the design methods of and decision-making process for green and energy-saving regional buildings.

Hail hazard modeling with uncertainty analysis and roof damage estimation of residential buildings in North America

This research presents a statistical approach for hail risk modeling that incorporates the uncertainties of hail model prediction to provide insight into assessing the roof damage of a residential house in hail events. By quantifying the inherent uncertainties in evaluating hailstorm characteristics, this study extends the current existing hail models. The hail data are sourced from the Community Collaborative Rain, Hail and Snow Network (CoCoRaHS) in the U.S. In the modeling process, the largest hail diameter reported in the CoCoRaHS database serves as a primary input variable to estimate the number of observations for the largest hail diameter, hailstorm duration, and hit rate. The assessment of hail risk in this study focuses on the probability of hail damage and resultant repair costs for five types of roofs in North America (unrated roof and impact-resistant roofs with UL 2218 rating classes 1 to 4). The probability of hail damage is calculated as the failure probability by integrating all individual hailstone hits having variable diameters during a hailstorm with fragility curves, which estimate the probability that hailstones will fracture asphalt shingles (allowing water infiltration) or that they dislodge enough granules to cause visible damage requiring replacement for aesthetic reasons. The results reveal that an impact-resistant roof (impact-resistant rating classes 1 to 4) is associated with lower hail risks, with 60 % to 98 % reduction on average compared to unrated roofs. This study provides a comprehensive uncertainty modeling approach for hail hazard and risk, enabling better-informed decision-making and risk management strategies.