Search Results (11)

High density old districts at the urban fringes of Asian megacities, such as Shenzhen, face significant thermal challenges due to dense building clusters, limited airflow, and heat retention. This study adopts an integrated approach combining Phoenics wind simulation, geographic information system (GIS) modeling, and spatial prototype analysis to assess and optimize the wind and thermal environments in these urban areas. It investigates how spatial configurations, including building density, height distribution, orientation, and green space integration, influence wind flow and thermal comfort. The results demonstrate that optimized spatial arrangements, including reduced building density, height adjustments, and strategic landscape design, improve ventilation and temperature regulation. Comparative analyses of different spatial prototypes reveal that radial configurations effectively channel external winds into the urban core, enhancing internal airflow, whereas rectangular layouts create wind shadows that hinder ventilation. Adjustments to building façades and vertical arrangements further mitigate pedestrian-level heat accumulation. Interventions in public spaces, including green roofs and vertical greening, offer cooling benefits and mitigate urban heat island effects. This study underscores the importance of aligning urban design with natural wind flow and offers a framework for sustainable landscape and architectural strategies in high-density, heat-prone environments. The findings offer valuable insights for urban planners and policymakers seeking sustainable development in similar megacities. Full article

With rapid urbanization, the urban heat island (UHI) effect has intensified, posing challenges to human health and ecosystems. This study explores the impact of sunlight exposure areas of artificial structures and human activities on land surface temperature (LST) in Hefei and Xuzhou, using Landsat 9 data, Google imagery, nighttime light data, and Point of Interest (POI) data. Building shadow distributions and urban road surface areas were derived, and geospatial analysis methods were applied to assess their impact on LST. The results indicate that the sunlight exposure areas of roofs and roads are the primary factors affecting LST, with a more pronounced effect in Xuzhou, while anthropogenic heat plays a more prominent role in Hefei. The influence of sunlight exposure on building facades is relatively weak, and population density shows a limited impact on LST. The geographical detector model reveals that interactions between roof and road sunlight exposure and anthropogenic heat are key drivers of LST increases. Based on these findings, urban planning should focus on optimizing building layouts and heights, enhancing greening on roofs and roads, and reducing the sunlight exposure areas of artificial structures. Additionally, strategically utilizing building shadows and minimizing anthropogenic heat emissions can help lower local temperatures and improve the urban thermal environment. Full article

Addressing climate change necessitates a conscious transition toward sustainable infrastructure solutions. Our vision involved transforming an experimental area into the University Experimental Center. This experimental building serves as a model for gray infrastructure implementation, taking into account its dimensions, layout, flooring, and material composition. Our study aims to compare the retention capacities of various types of vegetated roofs, as determined by different legislations. The findings indicate that the outcomes vary based on the regulations used. This variation subsequently influences the design of associated infrastructures, such as rainwater drainage systems, and the design of stressed structures. This is due to the impact of water quantity on the thermal response of a stressed structure. The water used to irrigate the vegetation layer, along with the water retained by the upper roof, has a positive impact on both the building and its surroundings. Initially, the system comprised two functional components: vegetated roofs and a reference roof. The integrated experimental roof shell, in conjunction with the frame, forms an autonomous system. This system serves as a segment for quantifying water retention, humidity, and temperature across diverse green infrastructure substrates. We analyzed the thermal response of experimental roof constructions and monitored the influence of water and precipitation. Our results indicate that the height of the substrate affects not only the retention capacity but also the thermal response of the vegetated roof. Full article

The present study investigated the cooling effect of extensive green roofs and green façades, at the pedestrian level, of a Mediterranean densely populated neighborhood. The ENVI-met environmental model was employed to simulate the microclimatic environment on a typical summer day. Thermal conditions of the study area were evaluated based on air temperature and the Mediterranean thermal stress scale of UTCI (Universal Thermal Climate Index). Three mitigation strategies were developed to ameliorate the thermal conditions in the examined area focusing on the efficacy of green façades, green roofs, and the synergetic effect of the green façade and green roof. The mitigation strategies’ performance was evaluated in characteristic design layouts of the study area, namely the following: a typical Mediterranean square, a church with a churchyard, an avenue, NS and EW street orientations, and courtyards. Results showed that compared to the existing configuration, the synergetic effect of the green façade and green roof achieved the greatest amelioration of the thermal conditions during the hottest hours of the day (12:00–18:00) since it produced an average Tair reduction of up to 0.7 °C and a UTCI reduction of 1.6 °C (both in the courtyards design layout). Among the examined design layouts, the courtyards produced the greatest reductions in air temperature and UTCI, whereas the EW streets were the lowest. Full article

The Renovation Wave for Europe initiative aspires to materialize the progressive greening of 85–95% of the continental older building stock as part of the European Green Deal objectives to reduce emissions and energy use. To realistically predict the energy performance even for a single apartment building is a difficult problem. This is because an apartment unit is inherently a customized construction which is subject to year-round occupant use. We use a standardized energy consumption response approach to accelerate the setting-up of the problem in pertinent energy engineering terms. Nationally instituted Energy Performance Certification databases provide validated energy consumption information by taking into account an apartment unit’s specific shell characteristics along with its installed electromechanical system configuration. Such a pre-engineered framework facilitates the effect evaluation of any proposed modifications on the energy performance of a building. Treating a vast building stock requires a mass-customization approach. Therefore, a lean-and-green, industrial-level problem-solving strategy is pursued. The TEE-KENAK Energy Certification database platform is used to parametrize a real standalone apartment. A supersaturated mini dataset was planned and collected to screen as many as 24 controlling factors, which included apartment shell layout details in association with the electromechanical systems arrangements. Main effects plots, best-subsets partial least squares, and entropic (Shannon) mutual information predictions—supplemented with optimal shrinkage estimations—formed the recommended profiler toolset. Four leading modifications were found to be statistically significant: (1) the thermal insulation of the roof, (2) the gas-sourced heating systems, (3) the automatic control category type ‘A’, and (4) the thermal insulation of the walls. The optimal profiling delivered an energy consumption projection of 110.4 kWh/m² (energy status ‘B’) for the apartment—an almost 20% reduction in energy consumption while also achieving upgrading from the original ‘C’ energy status. The proposed approach may aid energy engineers to make general empirical screening predictions in an expedient manner by simultaneously considering the apartment unit’s structural configuration as well as its installed electromechanical systems arrangement. Full article

Heat island effects raise the ambient air temperature in metropolitan areas by 4–5 degrees Celsius and can reach 10 degrees Celsius at their maximum. This phenomenon magnifies cities’ energy difficulties while reducing comfort. Mitigation strategies have been developed and recommended to deal with the issue. Methods to increase albedo and the utilisation of vegetation appear to be the most promising, with a reasonably high heat island reduction capacity. This paper examines the heat mitigation techniques and their effectiveness under Sydney’s climate conditions and compares strategies. We implement two perspectives, namely urban greening (green roofs, green pavements) and albedo (street, roof), and characterise urban surface structures, and Envi-met software is employed for our simulation method. Mitigation strategies show a cooling potential of 4.1 °C in temperature along this precinct during the heatwave period. Scenarios that increase high-albedo material on the road, pavements and rooftops and full mitigation show the maximum cooling potential. The mitigation strategies have higher predicted cooling potential on the peak ambient temperature, up to 1.18 °C, while having no or little impact on minimum ambient temperature. The outdoor thermal comfort based on PMV indices varies between a minimum of −0.33 in scenario seven in large layout areas to 3. However, the mitigation scenario presents more acceptable outdoor thermal comfort, but large layouts are predicted to have a hot condition. Full article

Indoor cooling is preferred during hot summers but unappreciated in cold winters. With this research, we aimed to clarify the cooling performances of roof greening throughout the year and identify the optimum roof greening coverage for the indoor thermal environment in Chenzhou, a city in China with hot summers and cold winters. The layout of buildings, building materials, and local climate data of Chenzhou were collected. The ENVI-met model was applied as the analytical tool after its accuracy was confirmed by a field experiment. The Kriging model was employed to interpret the annual effects of roof greening. The analytical results revealed that in Chenzhou, roof greening reduced indoor temperatures throughout the year, and the higher the coverage of roof greening, the greater the performance of indoor cooling. Moreover, hot climates enhanced the indoor cooling performances of roof greening. From the view of annual thermal perception, the increase in roof greening coverage reduced the duration of warm perceptions throughout the year and extended the perceptions of slightly warm, slightly cool, and cool. Generally, increased roof greening coverage improved the indoor thermal perception in Chenzhou throughout the year. The ENVI-met + Kriging model, an evaluation method of annual cycles, can be used to evaluate the annual performance of roof greening in terms of indoor thermal environment in other climate zones. Full article

Green roofs have received much attention in recent years due to their ability to retain rainwater, increase urban diversity, and mitigate climate change in cities. This interdisciplinary study was carried out on three historical green roofs covering bunkers in Wrocław, located in southwestern Poland. It presents the results of a three-year investigation of the water storage of these roofs. The study also presents soil conditions and spontaneous vegetation after their functioning for over 100 years. The soils covering the bunkers are made of sandy, sandy-loam, and loamy-sand deposits. This historical construction ensures good drainage and runoff of rainwater, and is able to absorb torrential rainfall ranging from 100 to 150 mm. It provides suitable conditions for vegetation growth, and forest communities with layers formed there. In their synanthropic flora, species of European deciduous forests dominate, which are characteristic of fresh or moist and eutrophic soils with a neutral reaction. Some invasive species, such as Robinia pseudoacacia, Padus serotina, and Impatiens parviflora, also occur with high abundance. Nowadays, historical green roofs on fortifications, although they have lost their primary military role, are of historical and natural value. These roofs can promote the nonmilitary functions of historical fortifications in order to strengthen the ties between nature and heritage. Protecting and monitoring historical green roofs should be included in the elements of the process of sustainable development and the conservation of these structures in order to mitigate climate change in the outskirts of the city. For this, it is necessary to ensure proper conservational protection, which, in addition to maintaining the original structure, profiles, and layout of the building, should include protection of their natural value. Full article

Balustrade architecture is mainly distributed in south and southwest China and southeast Asia. Dai dwellings in Yunnan, China, are a typical balustrade dwelling. Traditional dwellings of Dai contain the concepts of architecture, physics, ecology, and sustainability in space planning, building materials, and construction methods. At a time when the global climate environment is deteriorating and energy saving, emission reduction, and low-carbon life are advocated, Dai dwellings should be studied from the perspective of sustainable development, from which we can draw lessons and inspiration. This paper investigated plane layout, space structure, and materials of Dai dwellings, and found that traditional Dai dwellings are wooden frame structures with wood and bamboo; the roof has two layers and long overhang eaves, which is good for diverting rain water, shading and shelter, and integrating the building with the natural landscape as well. Analyzing the spatial characteristics and problems of Dai dwellings at present, discussing the sustainable development ideas of Dai dwellings, constructing Dai dwellings with low energy consumption and high quality of life, combining traditional culture with ecological technology, and designing a sustainable new green living model are beneficial to the inheritance of Dai residence culture. Full article

In recent years, urban flooding occurred frequently because of extreme rainstorms. Sponge city construction can effectively mitigate urban flooding and improve urban rainwater utilization. Low-impact development (LID) is regarded as a sustainable solution for urban stormwater management. In this project, a comprehensive evaluation system was developed based on environmental and economic benefits using the analytical hierarchy process (AHP) and the Storm Water Management Model (SWMM) of the United States (US) Environmental Protection Agency (EPA). The performance of four LID scenarios with the same locations but different sizes of green roof, permeable pavement, concave greenbelt, and rain garden were analyzed in the Sucheng district of Jiangsu province in China. Results illustrate that the green roof performed best in reducing runoff, while the rain garden performed worst. The LID combination scenario (1) that contained more green roof, permeable pavement, and concave greenbelt facilities, but fewer rain gardens had the better comprehensive performance on the basis of environmental and economic benefits. The combined scenario (2) (LID proportion of maximum construction area was 40%) could also be an alternative. This study provides a guide to optimize LID layouts for sponge city construction, which can also provide optimal selection for other sponge city constructions. Full article

Growing and densifying cities set a challenge for preserving and enhancing green spaces to cool urban spaces. Green roofs, involving the planting of vegetation on rooftops, are regarded as an alternative approach to enhancing urban greenery and urban cooling. For better cooling performances, it is essential to reasonably configure green roofs, especially in real and complex neighborhoods. Therefore, the aim of this paper is to investigate the impact of morphological characteristics of green roofs on pedestrian cooling in real and complex neighborhoods. In specific, based on an ENVI-met model, we studied the effect of greening layout, coverage ratio, vegetation height, and building height on pedestrian air temperature reduction in the tropical city of Hangzhou, China. Results indicate green roofs could generate moderate effects on pedestrian air temperature reduction (around 0.10–0.30 °C), while achieving a cooling performance of 0.82 °C. Green roofs in upwind zones were able to generate the most favorable cooling performance, while green roofs in downwind zones made slight differences to pedestrian thermal environments. Green roofs with a low coverage ratio were not useful for lowering pedestrian temperature, and a greening coverage ratio of 25–75% in upwind zones was cost-effective in real neighborhoods. Locations that were horizontally close to green roofs enjoyed better cooling performances. Increasing vegetation height could strengthen cooling effects of green roofs, while an increase in building height weakened the cooling performance. Nevertheless, higher building height could enhance pedestrian cooling performances because of building shading effects. In addition, because of wind effects and building shading, building height limits for the cooling performance of green roofs could be higher than 60 m. Full article