•Natural ventilation is dominant passive design strategy in tropical climate.•Maximum proficiency of natural ventilation depends on heat avoidance techniques.•Ventilation shaft especially active ...stack increases indoor air velocity.•Aperture size and building orientation elevate the efficiency of ventilation.
Energy consumption in the building sector is a major concern, especially in tropical climates where high temperatures and humidity force occupants to use electro-mechanical ventilation. Passive design strategies, in particular the application of natural ventilation, are one of the main techniques to moderate temperatures in buildings. Furthermore, many studies have shown reduced operating costs, better thermal comfort and indoor air quality, to be some of the advantages of the application of natural ventilation in buildings. Although existing studies support the efficiency of natural ventilation, the efficiency and practicability of architectural elements to maximise ventilation in buildings remains problematic. This study reviews studies on natural ventilation with other passive design strategies in tropical climates in order to support the argument for the application of natural ventilation in tropical climates. Through a review of studies on the operation of natural ventilation in buildings, it also identifies the most effective architectural elements and techniques in building façades and ventilation openings. The results indicate that ventilation shafts, window-to-wall ratio and building orientation should be applied in future construction. This study also identifies some further specific elements that are worth further investigation, including the shape of louvered windows, different forms of apertures and vernacular elements.
Passive ventilation techniques can both improve indoor air quality (IAQ) and reduce energy consumption and costs in buildings. In particular, using wind-driven ventilation as a passive design ...strategy can increase indoor air velocity in naturally ventilated buildings. In tropical regions, where there are only limited differences between indoor and outdoor air temperatures, wind-driven ventilation through a transom ventilation panel (TVP) can be a positive ventilation technique. In this study, we evaluated through experimental tests the efficiency of single-sided ventilation and cross-ventilation through a TVP in a unit within a high-rise residential (HRR) building. To this end, we carried out a series of numerical simulations to calculate the airflow patterns and the indoor air velocity for various outdoor wind speeds when cross-ventilation was applied. The results show that TVP can increase indoor air velocity by up to four times, depending on the outdoor wind speed and the location within the unit. Also, in windy conditions, the mean air change per hour (ACH) in a unit equipped with a TVP is 27% greater than a unit without a TVP. Moreover, a TVP can improve air change rate even when the outdoor wind speed is less than 0.02 ms−1.
•Cross ventilation is rarely applied on HRR buildings due to their compact form.•The ACH in the unit equipped with the TVP is up to 64% greater than that without the TVP.•A TVP can increase indoor air velocity up to 240% by making a pressure difference.•A TVP improves up to 107 ACH when the outdoor wind speed is about 2.45 ms−1.
As Malaysia continues to develop at a fast pace, the number of buildings in this country rapidly increases. Commercial buildings which include office buildings are one of the three major energy ...consuming sectors, which includes industrial and transportation sectors. Most Malaysian government office buildings tend to consume energy inefficiently due to lack of energy optimization. This study aims to analyse the energy performance as well as the factors that influence energy consumption in government office buildings. The chosen buildings for this case study are six government office buildings located in Kuala Lumpur, the capital of Malaysia. In this study, literature review has been conducted on the common factors affecting energy consumption in office buildings. The energy consumption data of the buildings were collected and analysed by comparison among the buildings and the SketchUp software. The Building Energy Intensity (BEI) of each building was also calculated using the formula in MS 1525:2019. Literature review and results from the case study show that air-conditioning system is the major energy consumer in office buildings, followed by lighting system while other office equipment consumed the least energy. The findings also highlight that energy consumption in office buildings is affected by non-design factors such as building occupants’ behaviour, number of building occupants, outdoor temperature as well as passive design factors such as building orientation and window-to-wall ratio. Recommendations were derived based on the findings from literature review and the case study for best practices to optimize energy consumption in government office buildings in Malaysia.
The increasing need for eco-friendly green building and creative passive design technology in response to climatic change and global warming issues will continue. However, the need to preserve and ...sustain the natural environment is also crucial. A building envelope plays a pivotal role in areas where the greatest heat and energy loss often occur. Investment for the passive design aspect of building envelopes is essential to address CO 2 emission. This research aims to explore the suitability of using integral-monolithic structural insulation fibre-reinforced lightweight aggregate concrete (LWAC) without additional insulation as a building envelope material in a high-rise residential building in the different climatic zones of the world. Polypropylene and steel fibres in different dosages were used in a structural grade expanded clay lightweight aggregate concrete. Physical and thermal properties of fibre reinforced structural LWAC, normal weight concrete (NWC) and bricks were measured in the lab. The Autodesk@Revit-GBS simulation program was implemented to simulate the energy consumption of a 29-storey residential building with shear wall structural system using the proposed fibre-reinforced LWAC materials. Results showed that energy savings between 3.2% and 14.8% were incurred in buildings using the fibre-reinforced LWAC across various climatic regions as compared with traditional NWC and sand-cement brick and clay brick walls. In conclusion, fibre-reinforced LWAC in hot-humid tropical and temperate Mediterranean climates meet the certified Green Building Index (GBI) requirements of less than 150 kW∙h∙m−2. However, in extreme climatic conditions of sub-arctic and hot semi-arid desert climates, a thicker wall or additional insulation is required to meet the certified green building requirements. Hence, the energy-saving measure is influenced largely by the use of fibre-reinforced LWAC as a building envelope material rather than because of building orientation.
Rainwater is an alternative water resource to fulfill sustainable management of freshwater particularly in the regions receive abundant annual amounts of precipitation such as tropical Malaysia. To ...collect and store rainwater, rainwater harvesting system has been practiced since ancient from horizontal surfaces mostly rooftop of buildings in urban areas. Nowadays, this method in modern urban areas with tall buildings is considered inadequate and uneconomical because the ratio of facade surface areas is much higher than the ratio of roof surface areas. On the other hand, all rain has a horizontal velocity due to wind acting upon rain droplets which is called wind-driven rain (WDR). Growing tall buildings and the presence of WDR phenomenon make building façade surfaces the available promising surfaces to harvest substantial rainwater vertically and more efficiently. This article presents a one-year field measurement results that aims at quantifying the WDR loads impinged on the vertical facade areas of a pilot building located at the main campus of the University Malaya in Kuala Lumpur, Malaysia. Detailed descriptions of the gauge design, building, the measurements of on-site WDR, rainfall duration time, and weather data are presented. Records show that monsoon winds characteristics have significant influence on the WDR loads on the building facades compare to horizontal rainfall intensity. Finally, the collected in-situ data are exploited to validate data and determine WDR coefficient (γ) to estimate the amount of WDR on a building façade via an empirical WDR relationship. Results show the feasibility of each square meter of vertical façade area to supply 12% of non-potable or 4.9% of potable water-usage per capita per day.
Purpose
Using a quantitative research method, health-care workers’ (HWs) well-being was taken as the dependent variable while the two independent variables were physical quality and service ...environment. This study aims to focus on the well-being of HWs in their physical environment.
Design/methodology/approach
This study used a hybrid method that is a combination of literature review and questionnaire survey. This study used quantitative research design which is a systematic study of phenomenon by collecting quantifiable data and performing statistical, mathematical or computational techniques. This study is conducted among HWs, with doctors and nurses at four Chinese government hospitals in the southern city of Changzhou (near Shanghai) as participants.
Findings
A total of 222 responses were obtained from a random sample of HWs from four hospitals in Changzhou City, Jiangsu Province. Three-fifth of the participants (n = 133, 60%) are satisfied with hospital equipment and half (n = 111.50%) of them are satisfied with the modern technology in place. About one-third (n = 67, 30%) are satisfied with ventilation and only one-fifth (n = 44, 20%) are satisfied with hygiene. Most HWs think it was necessary to provide tests for frontline workers.
Originality/value
In the wake of COVID-19 in 2020, HWs are working long hours every day facing high risk of infection and stress. This research investigates the satisfaction level and the difficulties experienced by HWs based on the current physical environment setting during COVID-19 pandemic.
Replace the normal weight aggregate with wastes or by-products materials is an appropriate method for producing a sustainable cement-based material. The replacement helps to have an energy-efficient ...component that reduces environmental impact. Time lag and decrement factors are vital wall system variables to evaluate thermal energy consumption in buildings. Thus, this study investigates the thermophysical properties of an innovative sustainable mortar and concrete containing oil palm boiler clinker (OPBC) as fine and coarse aggregate through an experimental approach. Then, time lag and decrement factor in different wall systems are calculated based on EN ISO 13786 through Python 3.7 (NumPy and math modules) and optimized using the response surface methodology (RSM). The results indicated mortar with OPBC has a slightly reduced decrement factor and increased time lag compared to a typical mortar. More significantly, the decrement factor of OPBC concrete was reduced by 34%, and its time lag increased up to 58% compared to conventional concrete.
The importance of low energy design in large buildings has encouraged researchers to implement different methods for predicting a building’s thermal performance. Atria, as energy efficient features, ...have been implemented to improve the indoor thermal environment in large modern buildings. Though widely implemented, the thorough study of atrium performance is restricted due to its large size, complex thermodynamic behavior and the inaccuracies and limitations of available prediction tools. This study reviews the most common research tools implemented in previous researches on atria thermal performance, to explore the advantages and limitation of different methods for future studies. The methods reviewed are analytical, experimental, computer modelling and a combination of any or all of these methods. The findings showed that CFD (computational fluid dynamic) models are the most popular tools of recent due to their higher accuracy, capabilities and user-friendly modification. Although the experimental methods were reliable for predicting atria thermal and ventilation performance, they have mostly been used to provide data for validation of CFD models. Furthermore, coupling CFD with other experimental models could increase the reliability and accuracy of the models and provide a more comprehensive analysis.
Identifying new energy saving methods in the building sector is essential due to limited natural energy sources and the rising population. Thermal mass materials have the ability to absorb and store ...heat before releasing it later on when necessary. They act as heat sinks during the daytime and as heat sources during the nighttime. Thermal performance is evaluated according to the specific heat capacity and specific latent heat. Applying thermal mass materials such as concrete is deemed a suitable strategy to reduce the energy consumption of buildings. Concrete with low thermal conductivity and high specific heat capacity is desirable in building construction. The aim of this study is to review factors affecting the heat storage capacity of concrete. In addition, common measurement methods of cement-based materials’ thermal conductivity, thermal diffusivity and specific heat capacity are reviewed. Various studies reveal that temperature, humidity, aggregate type, cementitious material type as well as phase change material (PCM) used influence the thermal properties of concrete. The advantages and limitations of PCM-concrete are also summarized in this study.
•Review thermal properties of concrete.•Sensible and latent heat capacity of concrete are discussed in detail.•Consider the relation between thermal properties of concrete and energy consumption in buildings.•Different methods of PCM-concrete incorporation are discussed.
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