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Reducing energy consumption and Greenhouse Gas (GHG) emissions is an essential part of the clean growth and climate change framework recently developed by the Canadian government, which emphasizes the importance of energy-efficient building constructions. In this paper, the effects of thermal mass and placement of the thermally massive layer within wall assemblies on the transient thermal performance of walls and energy performance of a case study office building were studied. Three climate conditions representative of the heating-dominated, temperate, and cooling-dominated climates were considered. As for the assessment of energy demands, two cases for the indoor air temperature were taken into account: (i) indoor temperature was maintained at 20°C throughout the year, and (ii) during summertime, there was a set-point of 24°C and a setback of 35°C during the rest of the day while during wintertime, the set-point and setback values were 22°C and 18°C, respectively. The cases were compared according to the resulting decrement factor, the time required to reach quasi-steady state conditions, amplitudes of changes of heat fluxes and indoor surface temperatures, and the energy demands. The results showed that, for the cases studied, the wall, for which the thermally massive layer is not directly exposed to the indoor and outdoor climate conditions, resulted in the lowest decrement factor, the minimum amplitude of changes of heat fluxes and indoor surface temperatures, and maximum time required to reach quasi steady-state conditions. As for the energy performance, on the other hand, the wall, for which the thermally massive layer is exposed to the interior and exterior climate conditions, performed best amongst the cases investigated. [ABSTRACT FROM AUTHOR]

This study explores the optimization of kinetic facades to promote environmental sustainability in building designs, addressing the critical issues of high energy consumption and CO2 emissions prevalent in the construction sector. The focus is on achieving an intricate balance between maximizing natural daylight and minimizing solar radiation using innovative kinetic facade designs. Parametric modeling tools are utilized in the design process to experiment with various facade configurations. The effectiveness of these designs is then validated using both digital and physical prototypes, with their adaptability to diverse climatic conditions evaluated through dynamic simulations. A key component of the study is the application of the Wallacei plugin for Grasshopper, which assists in multi-objective optimization to determine the most effective facade aperture ratios. The results demonstrates a substantial reduction in solar radiation levels, with a 70% decrease on the first floor and a 76% decrease on the seventh floor, achieved by optimizing aperture ratios. The study concludes that optimizing kinetic facades significantly improves building performance compared to traditional glass facades, offering an effective balance between daylight enhancement and solar radiation reduction, influenced by seasonal changes. It also emphasizes the importance of factors such as building height and the surrounding environment in facade design. Overall, the findings highlight kinetic facades as a viable solution for improving building efficiency and occupant comfort, suggesting a promising avenue for advancements in architectural design and construction. [ABSTRACT FROM AUTHOR]

Increasing the thermal resistance of masonry wall systems is one of the effective ways to reduce energy consumption in the operation of masonry buildings. This increase is also demanded by newer, more stringent energy codes. However, the effective thermal resistance (R -value) of masonry walls is affected by many factors, such as thermal bridging, which occurs in places where highly conductive structural components penetrate insulating materials. Thermal bridging is common when connecting masonry veneers to structural backup walls. Furthermore, quick and precise methods for estimating the R -value are needed for thermal design improvements and code-compliance calculations. This study presents a comprehensive literature review on key factors that influence the overall thermal performance of masonry walls, methods to effectively estimate and measure R -values, and improvements in thermal design. In addition to identifying the main technical and practical challenges and the corresponding progress made on each front, key design considerations, such as code compliance, material properties, insulation types, and location, as well as special ties and shelf angles types, are also discussed. This study summarizes critical information and recommendations that will help improve the thermal design of masonry walls, hence reducing the energy consumption of buildings. [ABSTRACT FROM AUTHOR]

The measurements for the short-wave solar reflectivity of a Reflective Coating Material (RCM) with various cleaning operations that were obtained in a previous study were used in this study to conduct numerical simulations in order to assess the moisture and energy performance of cool and black roofs when they were subjected to the weather conditions of Saudi Eastern Province and Kuwait City. The results of the numerical simulations showed that black roofs always work with less moisture than cool roofs. Because the highest relative humidity in the different components of the black and cool roofs was well below 80%, there was no risk of condensation and mold growth in these roofs. For both weather conditions of Saudi Eastern Province and Kuwait City, the results showed that installing cool roofs have resulted in increasing the heating energy loads in relation to black roofs. Conversely, the results showed that the decrease in the cooling energy loads due to installing cool roofs were typically much greater than the increase in the heating energy loads. As such, cool roofs have resulted in net energy savings in relation to black roofs. Replacing black roof by cool roof in Saudi climate, the results showed that the annual energy savings in the total energy load was 25% and 34% as a result of installing cool roof with RCM at no cleaning and weekly homemade cleaning, respectively. Additionally, replacing black roof by cool roof in Kuwaiti climate, the results showed that the annual energy savings in the total energy load was 23% and 31% a result of installing cool roof with RCM at no cleaning and weekly homemade cleaning, respectively. [ABSTRACT FROM AUTHOR]

In order to get more comprehensive operation performance on indoor environment quality (IEQ) and energy consumption, a long-time measurement and a field occupants' satisfaction survey on IEQ performance of the first three-star-operation-certified green office building in Ningbo city of China have been conducted, and environmental energy efficiency (EEE) also has been analyzed. Moreover, IEQ and energy consumption of the green case office building are compared with other green office example buildings of the same climate zone in other literatures. The results show that the actual indoor thermal environment of the green case office building isn't quite achieving the design goals with the Chinese standard of thermal comfort level II (GB 50736). Although indoor air quality of CO2 concentration and visual environment are consistent with the design goals, the indoor relative humidity doesn't reach the design goal in most of the year. The questionnaire survey results illustrate that the green case building has a high occupants' satisfaction on IEQ. The comparison results show that there is no obvious difference in indoor temperature and visual environment between the green case building and the green office example buildings in other studies. The results of occupant's satisfaction and CO2 concentration of the green case building are better than in other studies. However, the indoor relative humidity of the green case building in every season is much higher than in other researches. Energy use intensity (EUI) of the green case building is about 56.5 kWh/m2·a, which is much lower than the constraint value of the Chinese standard. The actual performance of the green case building is also evaluated by the indicator of EEE. The results of this article can provide useful reference for green building operational performance promotion and feedback for design phase optimization. [ABSTRACT FROM AUTHOR]

The theme of the energy requalification of historic buildings is addressed considering the Palaeontology Museum of Naples (Southern Italy). It is assessed whether, through non-invasive methods and without intervening on the building envelope, it is possible to obtain internal hygrothermal parameters suitable to allow both occupants' thermal comfort and satisfactory conservation conditions for the archaeological finds. In addition, a relevant reduction of energy requirements and CO2 equivalent emissions is required. Dynamic energy simulations are conducted regarding both the current configuration and the various possible modifications concerning the air conditioning system; the model is calibrated by comparison with real energy consumption data. The electric and primary energy are compared for the various cases. Furthermore, the internal hygrothermal conditions for occupants' thermal comfort and for conservation of the archaeological finds are analysed. Finally, the possibility of inserting a suitable and minimally invasive photovoltaic system is evaluated and an almost 'Double Plus-Zero Energy Building' is obtained. [ABSTRACT FROM AUTHOR]