Buildings In Singapore Research Articles

Waterproofing integrity and water tightness of buildings in the tropic

For tropical countries in Southeast Asia, frequent heavy rains and the local habit of using lots of water in wet areas such as toilets and bathrooms within dwelling units are the major reasons that waterproofing designs fail to prevent the water ingress into buildings. Unfortunately, not many studies on the effectiveness of waterproofing system for such climatic conditions and social habits have been reported. Results of studies conducted on various categories of defects related to water ingress and water tightness for public housing projects and others buildings in Singapore are reported. Examination of waterproofing failures in Singapore and other Southeast Asia countries showed the cause of the failure was because the waterproofing designs adopted were mainly copied from developed temperate countries in the earlier years. Based on the causes of waterproofing failures, revised details are proposed for tropical countries with frequent heavy rains and similar social habits to eliminate these failures in an integrated approach, that is, design, construction, and maintenance, to achieve efficiency, durability, ease of construction and maintenance, overall quality assurance, and cost effectiveness for the waterproofing system. Revised details adopted to achieve waterproofing integrity and water tightness of conventional and prefabricated buildings in the tropic are presented.

Space Efficiency of Tall Buildings in Singapore

Space efficiency in Singaporean tall buildings results from a complex interplay of historical, architectural, engineering, technological, socioeconomic, and environmental factors. The city-state’s innovative and adaptive approach has enabled it to overcome the challenges associated with skyscraper construction, leading to the development of some of the most advanced and sustainable high-rise structures in the world. However, there is currently a lack of detailed analysis on space utilization in Singaporean high-rise buildings. This study addresses this gap by examining 63 cases. The main findings of this research: 1. Residential functions, central core layouts, and prismatic shapes are the most frequent. 2. Concrete material with a shear-walled frame system is the preferred structural choice. 3. Average spatial efficiency is 80%, and the core-to-GFA (Gross Floor Area) ratio averages 17%. These metrics vary from a minimum of 68% and 5% to a maximum of 91% and 32%, respectively. These insights offer valuable guidance for Singaporean construction professionals, particularly architects, helping them make informed design decisions for high-rise projects.

Quantifying the effects of Singapore’s street configurations on people’s activity spaces

Although it is generally accepted that street configurations may influence people’s intra-urban travel, capturing the exact nature of that influence remains challenging. We frame this challenge as one of operationalization and measurement and attempt to quantify and analyze the impact of street configurations more precisely. We draw on geographic data science tools to suggest that street configurations may be captured using catchment area polygons. To illustrate our approach, we derive these polygons for every building in Singapore and show that catchment area sizes spatially cluster, thus acting as proxies for street configurations. Using a spatial error model, we demonstrate that these catchment area sizes partially explain people’s intra-urban travel, conceptualized as their activity spaces. That is, as street configurations lead to larger catchment areas, people’s activity spaces tend to shrink. We show that the explanatory power of catchment area sizes is distinct from, albeit correlated with, other built environment variables (such as amenity density and land use diversity) typically used to explain people’s travel. We conclude by considering the potential of our approach in broader urban geographical research agendas drawing on street configurations and other morphological influences in the study of socio-spatial processes.

Comparison of the environmental, energy, and thermal comfort performance of air and radiant cooling systems in a zero-energy office building in Singapore

In an experimental study set in Singapore’s tropical climate, we evaluated the thermal environmental performance, energy consumption, and thermal comfort of air and radiant cooling systems, operating at an operative and air temperature of 26 °C. 78 participants across five groups answered thermal comfort surveys in a crossover study design. Environmental performance metrics indicated that both systems produced similar conditions, with a noticeable difference in air velocity. The mean radiant temperature to air temperature difference was less than 0.5 °C in both systems. The radiant system exhibited a 33 % higher heat flux extraction than the air system and required less electrical power for the transportation of the cooling medium and ventilation air. Overall, the radiant system used 4 % less energy than the air system when controlled at 26 °C and 34 % when operated at 23 °C. Results show that radiant and air systems provided equal thermal comfort in cooling, with over 60 % of participants expressing satisfaction and ∼ 20 % voted neutral thermal satisfaction. ∼ 40 % of participants preferred cooler conditions, and ∼ 30 % desired increased air movement.

Material stock-service and circularity prospects of buildings in Singapore

Estimates of city-scale building material stocks and flows can contribute towards resource circularity opportunities. A bottom-up material flow analysis is carried out to track concrete, steel and embodied carbon in all Singapore buildings, from 2010 to 2020. Most inflows were directed to residential buildings, while the largest outflow originated from the demolition of private industrial buildings. In 2020, 472 million tonnes of concrete and steel stocks were embodied in buildings. Embodied carbon in public residential buildings is the highest (58.4 MtCO2e) among all building types. Resource efficiency of residential and industrial buildings, in terms of material use per service index, remained flat over the past decade, while that for commercial buildings rose. The cumulative outflows for the next 10 years can meet 17 % of projected material demand and deliver significant emissions savings. Efforts to promote material reuse and recycling can help deliver a low-carbon and circular built environment.

Energy flexibility quantification of a tropical net-zero office building using physically consistent neural network-based model predictive control

Building energy flexibility plays a critical role in demand-side management for reducing utility costs for building owners and sustainable, reliable, and smart grids. Realizing building energy flexibility in tropical regions requires solar photovoltaics and energy storage systems. However, quantifying the energy flexibility of buildings utilizing such technologies in tropical regions has yet to be explored, and a robust control sequence is needed for this scenario. Hence, this work presents a case study to evaluate the building energy flexibility controls and operations of a net-zero energy office building in Singapore. The case study utilizes a data-driven energy flexibility quantification workflow and employs a novel data-driven model predictive control (MPC) framework based on the physically consistent neural network (PCNN) model to optimize the building energy flexibility. To the best of our knowledge, this is the first instance that PCNN is applied to a mathematical MPC setting, and the stability of the system is formally proved. Three scenarios are evaluated and compared: the default regulated flat tariff, a real-time pricing mechanism, and an on-site battery energy storage system (BESS). Our findings indicate that incorporating real-time pricing into the MPC framework could be more beneficial to leverage building energy flexibility for control decisions than the flat-rate approach. Moreover, adding BESS to the on-site PV generation improved the building self-sufficiency and the PV self-consumption by 17% and 20%, respectively. This integration also addresses model mismatch issues within the MPC framework, thus ensuring a more reliable local energy supply. Future research can leverage the proposed PCNN-MPC framework for different data-driven energy flexibility quantification types.

Efficiency Analysis of the Photovoltaic Shading and Vertical Farming System by Employing the Artificial Neural Network (ANN) Method

Productive facades, consisting of photovoltaic shading and vertical farming systems, have been proposed as a means to improve the thermal and visual status of residential buildings while also maintaining energy performance and providing vegetables. However, how to quickly and accurately predict electricity and vegetable output during the numerous influencing architectural and environmental factors is one of the key issues in the early stages of design, and few studies have investigated the impact of such structures on both indoor environmental qualities and production performance. In this paper, we present a novel prediction method that uses experimental data to train and test an artificial neural network (ANN). The results indicated that using the Bipolar Sigmoid activation function to process the experimental data input to the artificial neuron network gives more accurate predicted results both in the yield of photovoltaic shading and vertical farming systems. In addition, this prediction method was applied to a typical high-rise residential building in Singapore to assess the self-sufficiency potential of high-rise residential buildings integrated with productive facades. The results indicated that the upper part of the building can meet 20.0–23.1% of the annual household electricity demand of a family of four in a four-room residential unit in Singapore and almost the entire year’s vegetable demand, while the middle part can meet 18.4–21.2% and 89.1%, respectively. The results demonstrated the importance of a productive facade in reducing energy demand, enhancing food security, and improving indoor visual and thermal comfort.

Features of Portuguese colonial architecture in South Asia in the period from XVI to XVIII centuries.

In this article, the author analyzes the Portuguese colonial architecture in the countries of South Asia in the period from the XVI to XVIII centuries. The author examines the military, civil and religious architecture built by the Portuguese during their presence in the South Asian colonies. Special attention is paid to the Portuguese colonial architecture of India (especially Goa) and Macau. Buildings in Singapore, Thailand, Malaysia and other former Portuguese colonies in South Asia are also considered. The author studies the process of formation and features of a special Portuguese colonial style in military (fortification), civil and religious (cult) architecture. The features in the design, decoration, as well as building materials of buildings are revealed. The novelty of the study lies in the fact that for the first time the samples of Portuguese colonial architecture in South Asia and their architectural features were comprehensively considered. The main conclusions of this study are the following. Firstly, on the one hand, the European architectural tradition has enriched the culture of the South Asian region. At the same time, different types of buildings show different degrees of influence. Secondly, on the other hand, Portuguese colonial architecture in South Asia itself has undergone significant changes under the influence of local cultural and climatic factors. Many of the changes made to classical European building designs were dictated by the weather and climatic features of the area. The choice of material was dictated by climatic and geological features. The culture of local civilizations also influenced the decoration and decoration of Portuguese buildings.

Calibration strategies for long-term strain forecasting in high-rise building columns

Concrete exhibits long-term time-dependent behavior due to creep and shrinkage that impacts the safety and serviceability of high-rise buildings. These rheological effects are difficult to predict due to their random nature, dependence on environmental conditions, and loading history. Current methods include the use of creep and shrinkage tests of structure-specific concrete samples to update compliance and shrinkage, and sophisticated numerical models for prediction of the long-term structural behavior. However, creep and shrinkage tests are time-consuming, and simulation requires reliable numerical models and often proprietary solvers that are not available to the structural health monitoring (SHM) practitioner. Further, uncertainty propagation in complex numerical models is rarely seen in the relevant literature. In contrast, data-driven prediction methods using SHM data and simplified analytical models have shown to be successful for prestressed concrete bridges. In this work, we investigate calibration strategies of creep and shrinkage models using SHM data toward data-driven forecasting of long-term time-dependent behavior of high-rise buildings. A calibration strategy is identified that enables significant and consistent improvement of forecasting of long-term time-dependent behavior. It is also shown that continuous calibration can provide good predictions at least 30 days ahead. First-order analytical uncertainty propagation formulas are also provided. The calibration strategies are evaluated on data from two residential high-rise buildings in Singapore. Recommendations to the SHM practitioners are also given.

Digital twin-enhanced predictive maintenance for indoor climate: A parallel LSTM-autoencoder failure prediction approach

Recently, the emergency of predictive maintenance (PdM) in the building industry has expanded from facilities to indoor climates, as air quality is highly relevant to residential health, comfort, and work efficiency. Besides, digital twin (DT) is considered as an effective solution for PdM deployment because it significantly enhances data-driven insights and enables proactive interventions. However, most existing studies on indoor climate focus on condition monitoring or anomaly detection rather than failure prediction, which has higher requirements for data and algorithms. In this study, the remaining useful life (RUL) and time shift (TS) methods are employed to split the prediction problem into the combination of a supervised and an unsupervised subtask, followed by the development of a parallel prediction model integrating the long short-term memory network (LSTM) and autoencoder (AE) methods. Besides, a DT-enabled PdM framework has been proposed for indoor climates, validated through the establishment of an online platform designed to reconstruct the 3D building model and demonstrate real-time monitoring and alert information of indoor climates. Experiments show the effectiveness of the proposed model under different warning times and fault severity through a comparison study with other 4 benchmark models based on a practical dataset collected from different buildings in Singapore, while the practical online platform serves as an illustrative case for future DT-enhanced PdM solutions.

Impact of architectural design strategies on the indoor natural ventilation of public residential buildings in Singapore

The architectural design pattern of the public residential buildings developed by Housing and Development Board (HDB) of Singapore has evolved gradually throughout the past decades. However, the fact is that although the new generations of HDB blocks built in recent years are designed to be modernized, the usage of air-conditioning has been increasing in comparison with the old generations. This study aims to investigate the ventilation performance of HDB blocks built in different generations from a historical view. By conducting computational fluid dynamics (CFD) simulations on five typical blocks built in different generations, the area-weighted wind velocities in various rooms of the target units were obtained. The effects of design factors on wind velocity ratio (VR) in corresponding spaces were analyzed and compared. The results show that the old generations with parallel plan layouts generally facilitate cross-ventilation while the new generations with centralized plan layouts usually generate single-sided ventilation which is more sensitive to incoming wind direction. Meanwhile, the window-to-wall ratio and shading depth of the studied facades were validated to have positive and negative relations to the VRs respectively. Though the correlations are insignificant, they show significant disparities between the scenarios under different incoming winds.

Analisis Prestasi Terma Penghadang Suria Luaran Sedia Ada di Kampung Admiralty, Singapura

External Solar shadings have long been designed as an integral part of a building’s facade for functional, aesthetic and privacy reasons. From a functional aspect, it is used to reduce heat and glare, thus helping to improve the thermal as well as lighting quality of the building. In a tropical climate, the yearlong sun radiation, especially those facing the eastern and western building facades with large glazed surfaces may show severe thermal and glare discomfort issues. This paper analyses the impact of the existing shading system of the vertical and horizontal fins and green facades of The Admiralty Village building in Singapore. A thermal imaging camera was used to detect thermal readings from all of the facade’s shading systems. From the result comparison, each facade of the building requires a different shading treatment due to the different sunlight angles. The south facade is best shaded with horizontal shading. East and west facades require shading that blocks sunlight entering at low angles. The north facade can be left unshaded. Green walls with highly dense vegetation perform more effectively than thermal insulation in reducing the cooling load of the building. This study further convinced the need for solar shading devices, especially in the southern facades of tropical countries.

Superhydrophobic bilayer coating for passive daytime radiative cooling

Abstract Passive radiative cooling is an energy-free cooling method by exchanging thermal radiation with the cold universe through the transparent atmospheric window. Spectrum tailoring of the radiative cooler is the key to daytime radiative cooling in previously reported works. In addition, radiative coolers with large-scale fabrication and self-cleaning characteristics should be further developed to improve their industrial applicability. Herein, we propose a bilayer radiative cooling coating with the superhydrophobic property and a scalable process, by covering TiO2/acrylic resin paint with a silica/poly(vinylidene fluoride-co-hexafluoropropylene) (SiO2/P(VdF-HFP)) composite masking layer. The strong Mie scattering in TiO2/acrylic resin paint contributes to high solar reflection, while the SiO2/P(VdF-HFP) masking layer is responsible for superhydrophobicity and synergetic solar reflection in the ultraviolet band, resulting in an effective solar reflectivity of 94.0 % with an average emissivity of 97.1 % and superhydrophobicity with a water contact angle of 158.9°. Moreover, the as-fabricated coating can be cooled to nearly 5.8 °C below the temperature of commercial white paint and 2.7 °C below the local ambient temperature under average solar irradiance of over 700 W m−2. In addition, yearly energy saving of 29.0 %–55.9 % can be achieved after the coating is applied to buildings in Phoenix, Hong Kong, Singapore, Guangzhou, and Riyadh.

Energy savings and thermal comfort in a zero energy office building with fans in Singapore

Elevated air movement produced by fans can offset air-conditioning energy requirements by allowing temperature setpoints to be raised without compromising thermal comfort. These advantages are even greater in hot and humid climates that inherently have large and sustained indoor cooling requirements. Few studies have assessed the in-situ benefits of fans in actual buildings. We installed ceiling and desk fans into a Zero Energy office building (675 m2) in Singapore. Across an 11-week period, 35 occupants alternated between two conditions (no fan vs. fan): 24 °C setpoint with fans off, and 26.5 °C setpoint with fans on. When the temperature setpoint was raised and elevated air movement was provided, a 32% energy reduction was obtained. The energy savings accrued without any negative impacts occurring on thermal satisfaction. Overcooling caused by thermal preference to slightly warmer and warmer conditions was substantially reduced from 33 to 9%. No changes in perceived air-staleness or self-reported alertness and ability to concentrate occurred either, indicating parity across the no fan and fan conditions. Although occupants primarily relied on ceiling fans at the 26.5 °C setpoint, they were by default on at the beginning of each day, giving less incentive to use the desk fans. Our study took place in a high-performance Zero Energy building, whereby thermal dissatisfaction was already low (7%). Therefore, notable changes did not occur, but significant improvements to thermal comfort could still occur in buildings that are unable to maintain high levels of thermal satisfaction.

Enhancing Urban Living with Automatic Parking Management Systems : A Comprehensive Review and Case Study

As urbanization continues to rise, the need for efficient and safe parking solutions has become more important. In recent years, automatic parking management systems have been developed to address this need. This paper presents a comprehensive review of automatic parking management systems. It discusses the various types of automatic parking systems, the components of an automatic parking management system, and the benefits of implementing such a system. The paper also presents a case study of an automatic parking management system implemented in a commercial building in Singapore. The case study evaluates the effectiveness of the system and highlights the challenges faced during the implementation process. The results of the study suggest that automatic parking management systems are an effective solution for managing parking in urban areas.

Experimental assessment of thermal and acoustics interactions on occupant comfort in mixed-mode buildings

Mixed-mode buildings use natural ventilation (NV) through operable building envelopes (e.g., windows) and mechanical air-conditioning (AC) systems to condition indoor spaces with the goal of energy savings without compromising occupant comfort requirements. As a result, occupants within such buildings experience different thermal and acoustic conditions. In mixed-mode buildings, however, there is no clear guideline on assessing or predicting occupants’ thermal perception (e.g., thermal sensation and acceptability) and the interaction effects between thermal and acoustic comfort. This study investigates thermal and acoustic comfort as well as their interaction effects in mixed-mode buildings under NV and AC modes. A field study was conducted in a mixed-mode office building in Singapore with a tropical climate. The results showed that subjects’ actual thermal sensation and thermal acceptability were affected by the operation modes. Elevated air movement by ceiling fans improved subjects’ thermal acceptability, particularly in the NV mode. The results indicated the need for a different thermal comfort model even when switching between NV and AC modes within the same day. Traffic noise also significantly affected thermal sensation and thermal acceptability at noise level higher than 55 dBA. The findings suggest that mixed-mode buildings are potentially applicable in the tropics and provide valuable information on the practical operation of mixed-mode buildings from thermal and acoustic perspectives. Future research needs to investigate how to integrate thermal and acoustic studies and their results into mixed-mode operations to improve building energy efficiency and occupant comfort.

Estimation of anthropogenic heat from buildings based on various data sources in Singapore

Heat released from the energy consumption in buildings (QB) is an important component of anthropogenic heat, which is a major contribution to the urban heat island (UHI) phenomenon. However, it is still a challenge to integrate all the available data to improve the estimation of QB due to inconsistences among multiple data sources. This paper presents a solution to estimate the anthropogenic heat from buildings in Singapore by classifying the buildings into the electricity consumption sectors based on a random forest classification model using multiple data sources. The classification model achieves a cross-validation accuracy score of 95% by using building use type, land use type of land parcel where the building stands, location and area as predictors. Based on the classification result, the annual average QB from the commercial buildings (CS), Housing and Development Board (HDB) apartments, private apartments and condominiums (AC), and landed properties (LP) were estimated to be 12.1, 4.4, 3.2 and 1.1 W m−2 on a 200 m-by-200 m grid, respectively. QB was approximately 9% of the net all-wave radiation in Singapore in 2015. Our approach can serve as a useful tool for integrating datasets from different sources with inconsistent categorizations, and our results can benefit urban planning as well as urban climate modeling at both microscale and mesoscale.

Impacts of a highly reflective stainless-steel façade on a surrounding building: A case study in Singapore

Few studies have assessed the inter-building direct reflection effect on building daylight and thermal environments with in-depth analysis based on onsite measurements. Therefore, it remains unclear how to quantify this direct reflection effect from field measurement results. To address this issue, this study conducted field measurements in a school building in Singapore affected by a surrounding highly reflective stainless-steel façade and proposed a method to quantify the changes in building daylight and thermal environments caused by the reflective façade. Results show that the daylight and thermal environments of the tested classrooms behave differently in the affected period (AP) and non-affected period (NAP) due to the direct reflection effect of the reflective façade. A 1-W/m2 increase in outdoor solar radiation (RS) may cause an additional 0.17–0.74 lux (26%-121%) increase in indoor illuminance (Ig) during the AP compared with the NAP. Moreover, increasing outdoor air temperature (To) by 1 °C will cause an additional 0.06–0.51 °C (8%-63%), 0.25–0.73 °C (27%-69%), and 0.26–0.62 °C (39%-87%) increase in the indoor air temperature (Ta), external glass (Tg) and wall (Tw) surface temperatures during the AP, respectively. Furthermore, the impact of the distance between the affected room and the reflective façade (DA-B) on the reflection effect was also evaluated in this study. The main purpose of this study is to display insights we learned from our case study, hoping to raise researchers’ attention to the adverse environmental impact of using highly reflective building materials.

Indoor Thermal Environment in Different Generations of Naturally Ventilated Public Residential Buildings in Singapore

This study aims to evaluate and compare the indoor air velocities and thermal environment inside different generations of public residential buildings developed by the Housing and Development Board (HDB) of Singapore and analyze the impact of façade design on the indoor thermal environment. To achieve this goal, several case studies were carried out, namely, five typical HDB blocks built in different generations from the 1970s to recent years. Firstly, these five blocks with different façade design features were simulated to obtain the indoor air temperatures for both window-closed and window-open scenarios by using the EnergyPlus V22.2.0 (U.S. Department of Energy) and Design-Builder v6 software(DesignBuilder Software Ltd, Stroud, Gloucs, UK). Meanwhile, the computational fluid dynamics (CFD) simulations were conducted to obtain the area-weighted wind velocities in the corresponding zones to evaluate the indoor thermal comfort. Accordingly, the effects of façade design on indoor air temperatures under both the window-closed and window-open conditions were compared and analyzed. Positive correlations between the facades’ window-to-wall ratio (WWR) and the residential envelope transmittance value (RETV) and Ta were confirmed with statistical significance at a 0.05 level. Furthermore, the indoor thermal comfort based on the wind open scenarios was also investigated. The results indicate that the thermal environment can be greatly improved by implementing proper façade design strategies as well as opening the windows, which could result in an average 3.2 °C reduction in Ta. Finally, some principles were proposed for the façade design of residential buildings in tropical regions with similar climate conditions.

Experimental and simulation assessment of an adaptable cooling coil in the tropics

Overcooling or too high humidity issues may occur when the cooling coil in the central air-conditioning system is inadequate to meet both room temperature and humidity requirements, which might affect indoor thermal comfort, air quality, and building energy efficiency. Developing more advanced cooling coils to adapt to cooling load changes is one of the promising solutions to overcome these issues. This paper presents both experimental and detailed simulation results for an “adaptable coil”, in which the coil row number is changed based on the building cooling load. Theoretically, when fewer rows are activated at part-load conditions, the coil’s effective heat transfer area is reduced, which enables the coil surface temperature to be lower; hence the coil dehumidification performance can be improved. Actually, from our experimental study on a small-sized coil, we found that the adaptable coil shows an average 0.8% relative humidity reduction, while its water flow rate is more stable than a conventional coil. We also conducted detailed EnergyPlus simulations for a typical large-sized building in Singapore and found that the adaptable coil shows about 2.8% of relative humidity reduction and negligible overcooling reduction. Moreover, the adaptable coil shows better performance in reducing overcooling and space humidity, when the coil is heavily oversized and a large minimum airflow fraction is set. In summary, the adaptable coil does not show significant humidity and overcooling reduction advantages for a properly sized and well-operated air-conditioning system. Though with operational flexibility, the benefits of the adaptable coil are not as promising as expected; nevertheless, these results and conclusions may be valuable for future studies focusing on similar solutions for overcooling and high humidity issues.