Building Energy Codes Research Articles

A BIM-integrated Thailand building energy code framework for building envelope thermal requirements in a conceptual design stage

This work presents the development of a building energy code (BEC) of Thailand compliance framework during conceptual design stages (CDS) using building information modeling (BIM) through visual programming language (VPL). The proposed method included five steps: (i) establish a commercial building reference; (ii) develop a BIM base model; (iii) create a BIM overall thermal transfer value (OTTV) and roof thermal transfer value (RTTV) calculation model with VPL scripts; (iv) test the BIM framework with various scenarios; and (v) verify the results with Thailand BEC software. The findings revealed an insignificant difference between the results from the BIM calculation model and those estimated by the Thailand BEC software. This study demonstrated that using BIM with VPL for OTTV and RTTV calculations during the CDS may be implemented automatically, which could help designers make timely decisions to comply with Thailand’s BEC, considering building design, materials, and fenestration ratios.

Path to Net Zero: Understanding the Building Energy Efficiency in Different Climates across Various Building Types

This study analyses the determinants of building energy efficiency in different climate zones and user types. The energy consumption of buildings in different climate zones can be affected by well-known determinants in different ways. So do the buildings with different user types. The primary aim of this study is to investigate how building energy efficiency is determined in five major climate zones and four main property types. This study uses the global building data (Points Achieved dataset) from the Leadership in Energy and Environmental Design (LEED) rating system 2010 to conduct three cross-sectional tests with logit regression models. The results confirm that the determinants of building energy efficiency are the location of the building, adoption of Building Energy Codes (BECs), climate zones, building types, regional economic development level (namely Gross National Income—GNI, Purchasing Power Parity—PPP) and population density. However, the impact of the determinants varies considerably in different climate zones or for different building types. This is the first empirical study exploring building energy efficiency and how it is determined in different climate conditions and user types. The findings are helpful for the stakeholders, such as policymakers, developers, and local authorities, when they hope to implement measures to improve building energy efficiency and the policy/regulation to boost it. Each building requires specific measures that suit its different climate zones or building types to enhance energy efficiency.

Comparative analysis of residential building decarbonization policies in major economies: insights from the EU, China, and India

The global building sector, responsible for over 30% of CO2 emissions, necessitates urgent decarbonization efforts. This paper examines residential building decarbonization policies in three major economies—the European Union (EU), China, and India. It provides an overview of diverse policies through policy landscape analysis and delves into the design specifics with a detailed policy intensity analysis of building energy codes, information disclosure, and financial incentives in each region. Our findings reveal a diverse mix of policies targeting residential building decarbonization in all three regions. While the EU and China have long-established diverse policy instruments, India's building energy efficiency policies are relatively recent and limited. Detailed analyses of building energy codes, information disclosure, and financial incentives expose variations in ambition, scope, and implementation, even with shared policy instruments. Significant advancements in building energy codes, particularly in stringency and compliance checks, are evident in the EU and China. Conversely, India faces a notable obstacle with limited adoption of residential building energy codes, impacting its journey towards net-zero. The EU leads in building energy labelling policies, while China and India encounter various challenges hindering widespread implementation. Financial incentives across the three regions predominantly take the form of subsidies, potentially straining public budgets. The study concludes with reflections on the pressing need for future research extending beyond the operational phase of buildings.

Shedding Light on Financial Sustainability: Analyzing the Economic Implications of Energy-Efficient Lighting in the Construction Industry

Energy is widely recognized as a critical production factor across numerous industries. Energy efficiency is a method by which the expansion of energy consumption is managed and restrained. The main goal of this research is to investigate the financial implications of energy-efficient lighting in the building sector.The objectives of the paper were to: evaluate the current adoption and market share of energy-efficient lighting technologies in the construction sector, assess the economic impact of energy-efficient lighting, including cost-effectiveness, potential energy savings, and greenhouse gas emission reductions, analyze the effects of energy-efficient lighting on worker safety, productivity, and overall project costs in the construction sector, identify barriers to adoption and recommend policy changes and incentives to promote the widespread use of energy-efficient lighting in the construction sector in Pakistan.The methodology of the research follows the quantitative approach, data which was used to achieve the objectives includes literature, data sources, and project details on the construction industry from 2015 to 2021. Literature analysis and Data metrics were used to analyze of data.Studies found that energy-efficient lighting not only provides significant long-term cost savings but also improves environmental sustainability by lowering greenhouse gas emissions and energy consumption. Further, the literature analysis shows the beneficial relationship between adequate lighting and improved worker well-being as well as project efficiency, even though empirical data on these topics may be scarce.The study suggested that to overcome barriers and optimize the advantages of energy-efficient lighting, it is important to increase knowledge, provide financial incentives, improve access to eco-friendly construction materials, and strengthen compliance with building energy codes.

Simulating the impact and policy implications of telework on home energy use and emissions in Canada

Statistics indicate that after the COVID-19 pandemic, many individuals have opted to work remotely for at least a few days each week. This study investigates the impact of teleworking on energy consumption and carbon emissions in Canadian homes. Four residential building models, aligned with the 2020 requirements of the National Building Code of Canada (NBC), were investigated across six Canadian climate zones. The findings of this study reveal that the increase in energy consumption and CO2 emissions due to teleworking varies according to the type of building and the number of thermal zones. For the selected single-zone house models, the maximum increase in energy consumption and CO2 emissions were 11% and 10%, respectively occurring in a row house two-story building. For the three-zone house models, the increase was 5%. Also, results indicated that full-time teleworking in a four-storey multi-family building with 12.5%, 50% and 100% teleworking ratios increased the total energy of the building by 1%, 4%, and 10%, respectively. The second phase of this study investigated possible enhancements to building energy codes, focusing on the National Building Code of Canada, to address increasing daytime occupancy resulting from teleworkers, retirees, and other occupants.

Economic optimization of exterior wall insulation in Chinese office buildings by coupling artificial neural network and genetic algorithm

Envelope insulation is an essential measure to reduce building energy consumption and is the focus of many building energy codes. In China, the current standard (GB 55015-2021) only specified limit values for the thermal conductivity (U) of the exterior walls, and it ignored variations in building characteristics and internal parameters. Therefore, it is difficult for architects to quickly determine the exterior wall U-value in building design and retrofit. To address this issue, the exterior wall U-values of office buildings in China were economically optimized by TRNSYS, ANN, and GA. To begin with, the effect of enhancing exterior wall insulation on the heating and cooling energy consumption of office buildings was investigated by TRNSYS software, taking into account variations in building characteristics. Moreover, the exterior wall U-values of office buildings were optimized by coupling ANN and GA. The results showed that the design values of the GB 55015-2021 did not achieve the optimal results in China, and the most economical exterior wall U-value was 0.24 W/(m2·K) in Harbin, 0.24 W/(m2·K) in Beijing, 0.42 W/(m2·K) in Changsha, 1.82 W/(m2·K) in Guangzhou, 0.66 W/(m2·K) in Kunming. Compared with the pre-optimization, the annual life cycle cost of building heating and cooling reduced by 0.96 % in Harbin, 2.07 % in Beijing, 1.44 % in Changsha, 1.68 % in Guangzhou, and 7.37 % in Kunming. In addition, variations in building parameters should be considered in the design phase of new buildings or in the renovation of old buildings, such as internal heat gain, which may lead to different optimal results.

Critical Analysis of Institutional and Regulatory Framework for Building Stock Energy Efficiency and Transition in Pakistan

Climate change has emerged as a global focal point, notably affecting vulnerable countries like Pakistan. The country faces heightened risk, prompting concern among many due to its susceptibility to climate-related hazards. An imperative challenge arising from this phenomenon is the necessary shift towards sustainable energy, particularly concerning energy consumption within the building sector. Buildings significantly contribute to daily energy usage and subsequent GHG emissions. In Pakistan, transitioning to energy-efficient building stock holds pivotal importance in mitigating climate change impacts. This hinges on establishing a robust institutional framework and regulatory structure centered around energy efficiency. While Pakistan possesses policies and national guidelines advocating for energy-efficient buildings, their practical enforcement and application remain inadequate. The inception of the Building Energy Code of Pakistan in 1990, based on ASHRAE 90.1 standards, marked a step forward. However, obstacles rooted in institutional weakness and limited capacity building have impeded its effective adoption and adherence. Although the Energy Provisions of 2011 introduced modifications, their scope remained confined mainly to commercial structures. This paper conducts an extensive assessment of Pakistan's existing institutional and regulatory framework for building energy efficiency and transition. Drawing on literature insights and stakeholder perspectives, an in-depth understanding of prevailing policies and institutions uncovers underlying reasons for non-compliance and limited implementation. Additionally, input was gathered from stakeholders through interviews, aiming to identify barriers obstructing the reinforcement of building energy efficiency measures in Pakistan. Discourse and narrative analysis, informed by literature and stakeholder interviews, revealed the significance of awareness, participation, coordination, capacity building, technical expertise, finance, and resources as key factors contributing to deficient compliance and implementation of existing codes and policy guidelines. This paper also proposes actionable recommendations to expedite the transition towards a sustainable, energy-efficient building stock in Pakistan.

Conceptual Cross-Theoretical Assessment Model for Practitioners’ Compliance Behavior with Building Energy Codes

Conceptual Cross-Theoretical Assessment Model for Practitioners’ Compliance Behavior with Building Energy Codes

Carbon Neutrality in the Building Sector of the Global South—A Review of Barriers and Transformations

This work provides a review of economic, technical, sociocultural, political, and technological barriers that impede carbon neutrality in the building sector of countries in the Global South. These barriers include limitations in public and professional awareness, knowledge, and skills in the construction industry, the lack of ambitious energy codes and green building rating systems, the lack of green financing schemes and investment, costs of materials and technology, and limitations in regulations. Finally, this article recommends five transformations to address the critical barriers and enable net-zero emission status in the building sector of countries in the Global South. These transformations include environmental data collection, stringent building energy codes, and green building system certifications, lifecycle-based thinking and circular design, education enhancement and workforce development, and net-zero emission business practices.

Enhancing Building Energy and Thermal Performance in Metro Manila, Philippines through Computational Fluid Dynamics-Assisted Analysis and Optimization

This study presents a detailed investigation of the energy and thermal performance of buildings in the Philippines’ metropolitan cities, targeting sustainability and indoor comfort against the backdrop of the country’s tropical maritime climate. Utilizing a blend of occupant surveys, energy audits, climate data analysis, and building envelope assessments, the research employs Computational Fluid Dynamics (CFD) simulations to accurately evaluate energy use and thermal behaviors in residential and commercial structures. Key findings include distinct nighttime energy consumption patterns in residential buildings and the identification of climatic challenges such as high temperatures and humidity. The study proposes effective design interventions like enhanced ventilation, shading solutions, and the integration of Phase Change Materials (PCMs) for improved thermal efficiency. Significantly, the research contributes to policy development by suggesting updates in building energy codes and advocating for energy-efficient practices. Overall, the study provides actionable insights for enhancing building sustainability and occupant comfort in urban Philippine settings.

Heating electrification in cold climates: Invest in grid flexibility

One strategy to significantly reduce greenhouse gas emissions in end-use sectors such as building heat is to switch from fossil fuels to electricity. To date, electricity consumption follows a regular and predictable pattern; however, electrifying building heat, which is driven by ambient temperature, causes this pattern to change. Previous work has not fully addressed the implications of building heat electrification on the timing and magnitude of peak demands and on flexibility requirements of the electricity grid. In this work, a high-resolution heating demand model, featuring building stock turnover forecasts, is developed, and applied to British Columbia. The study determines energy, capacity, and flexibility requirements by computing regional energy load profiles for space and water heat. Six scenarios were developed to examine the decarbonization potential in the residential and commercial building sector, considering increased heat pump adoption, building envelope energy efficiency improvements, and the implementation of building energy codes. With an emphasis on building stock improvements, 90% heat pump penetration results in only 6% increase in electrical energy even with an annual population growth rate of 1.1%; however, this scenario leads to a 37% increase in peak electricity demand. Over the time-period considered, building energy codes and retrofit rates contribute relatively little to achieving net-zero emissions in the buildings sector, while building heat electrification has significant impacts on future flexibility requirements of the electricity grid.

Correlation analysis of building parameters according to ASHRAE Standard 90.1

Building energy codes promote efficient energy management in both conventional and eco-friendly buildings. These codes are periodically updated to reduce energy consumption and carbon emissions. However, these updates can induce correlations among building parameters, which could lead to incorrect results when creating or analyzing data sets based on them. This study aims to investigate the impact of correlations in building parameters caused by the trend of updates in building energy codes. The most widely used building energy standard, namely Standard 90.1 of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), is utilized to understand the trends of energy codes. We confirm that periodic updates to ASHRAE Standard 90.1, representative of numerous energy standards and codes, induce correlations in the input parameters. Moreover, we analyze the problems caused by these correlations through sensitivity analysis and Principal Component Analysis (PCA). Consequently, the sensitivity index of parameters with correlations increases while the importance of parameters without correlations decreases. In the PCA, the number of parameters required to explain more than 95 % of the variance in the raw data changed. This study's findings highlight the need to carefully consider correlations when analyzing building energy code-impacted data and provide insight that enhances the accuracy of the interpreting parameter relation in such data analysis.

Developing structural sandwich panels for energy-efficient wall applications using laminated oil palm wood and rubberwood-based plywood/oriented strand board

In this work, a new type of structural sandwich panels made with laminated oil palm wood core and rubberwood-based oriented strand board (OSB)/plywood faces were introduced for energy-efficient wall applications in Thailand. Effect of the manufacturing process and material parameters including adhesive content (250 g/m2 and 500 g/m2), core configuration (cross or parallel laminated oil palm lumber) and density (low and medium) and face material type (rubberwood-based OSB/plywood) on panel’s properties were explored. The panels were produced using two-component polyurethane adhesive and a constant clamping pressure of 0.6 MPa. Adhesive content of 250 g/m2 was found to be sufficient for gluing all layers, with wood failure percentage of more than 80% as required by the standard. In-plane dimensional stability of the panels was mainly affected by the core configuration; it was better for cross laminated oil palm wood core sandwich panel. Higher core density resulted in increased density, thermal conductivity and compressive strength in the major direction but lower thermal resistance of the panel. The plywood face sandwich panels provided slightly higher compressive strength than OSB face sandwich panel, and their failure mechanisms were also different. The heat loss of these panels was about one-third of concrete and brick walls, hence, they can provide better insulation for indoor space. Based on the measured thermal conductivity, it was expected that these panels would pass the energy criteria according to Building Energy Code of Thailand. Thus, from the energy saving and sustainability perspectives, these panels can potentially be used as energy efficient wall panels for buildings, not only for Thailand but also for other tropical countries, where the oil palm wood and rubberwood resource is available.

Renovation of an Academic Building’s Envelope, Lighting, and Air Conditioning System According to Thailand Building Energy Code for Energy Consumption Reduction

This study evaluated the feasibility of building renovation with regard to the aspects of economy and energy. An academic building located in Bangkok, Thailand was selected for a case study. Four sub-systems, namely, the building envelope, lighting system, air conditioning unit, and electrical system, were renovated. From the energy perspective, Thailand’s Building Energy Code was used as an evaluating standard, and the BEC software (Version 2.6.0) was employed for the calculations. The economic feasibility of the renovation was determined on the basis of the internal rate of return and discounted payback period. It was demonstrated that the renovation can result in a reduction in the annual energy consumption of the entire building by up to 55.44%. In regards to economic feasibility, the renovation project can achieve a payback period of 4.98 years with 20.89% IRR. In addition, the renovation of a building can lead to spare capacity of the transformer for electric vehicle charger loads. Thus, the renovation of an old building into an energy-efficient building in compliance with building code can afford benefits both in terms of electricity consumption reduction and decreased energy cost for the project owner and provide opportunity for the building to support future load.

A Review of the Evaluation of Building Energy Code Compliance in the United States

Building energy codes are essential tools for achieving energy efficiency in buildings. However, the full energy savings potential of these codes can only be realized if buildings are constructed in compliance with them. Therefore, evaluating building energy code compliance is crucial in bridging the gap between the energy efficiency requirements set by energy codes and the actualized energy savings achieved. An energy code compliance evaluation serves as a mechanism to assess construction practices, evaluate the effectiveness of code enforcement, identify gaps in compliance, and guide strategies for improvement through training and education. Conducting code compliance evaluation activities involves field studies that require careful design and significant resources. Historically, more emphasis has been placed on developing and adopting building energy codes, while efforts to evaluate compliance have been relatively limited and lacking consistent approaches. The passage of the 2009 American Recovery and Reinvestment Act (ARRA), which mandated that states create plans for achieving 90% compliance within eight years, stimulated the need for an energy code compliance evaluation. As a result, federal, state, and local governments, and utilities have invested in the development of methodologies and tools for code compliance evaluation studies. This paper reviews the code compliance evaluation studies conducted in the United States over the past three decades. It describes and compares the methodologies and metrics used to assess building energy code compliance, summarizes the general elements and steps involved in the evaluation process, and discusses common issues in these studies. Over time, code compliance evaluation methodologies have evolved from isolated development within individual states, regions, and utilities, to widely accepted protocols applicable across different states and local jurisdictions. There has been a transition in compliance metrics, shifting from historical compliance rates to energy-consumption-oriented approaches.

Adopting occupancy-based HVAC controls in commercial building energy codes: Analysis of cost-effectiveness and decarbonization potential

Recent research has shown the energy-saving potential of occupancy-based HVAC controls (OBCs) in commercial buildings. However, building energy codes have not fully adopted this technology. This study aims to evaluate the cost-effectiveness and decarbonization benefits of OBCs and provide guidance for integrating occupancy sensors into building energy code development. To this end, a parametric simulation using EnergyPlus and a nationwide cost-effectiveness analysis are carried out considering three building types and 40 representative cities in the U.S. The findings reveal that the current cost-effectiveness performance of OBCs is limited due to the high cost of occupancy sensors. However, incorporating the societal cost of carbon factor in future energy and environmental policy could greatly enhance the actual cost-effectiveness performance. Besides, a reduction in the cost of occupancy sensors to approximately 60% of the current price level could also greatly shorten the discounted payback period of OBCs. Additionally, OBCs demonstrate significant potential in building decarbonization, with potential CO2 emissions savings of more than 5.56 million metric tons across the three building types and 40 selected cities. Finally, policy implications are provided to guide the incorporation of occupancy-based HVAC controls in future energy codes.

A Study on Transparent Type Envelope Material in Terms of Overall Thermal Transfer, Energy, and Economy for an Office Building Based on the Thai Building Energy Code

Energy consumption in buildings has increased significantly as population and economic activities are concentrated in urban areas. Air conditioning accounts for a significant percentage of energy consumption in buildings, especially in tropical climates. The main area where heat can be transferred into the building is through glass windows. Thus, this study aims to evaluate feasibility in terms of overall thermal transfer value (OTTV), energy, and economics for retrofitting different glass materials in an office building in Thailand by using building energy code (BEC) software. The software uses Thailand’s building energy code as the standard to evaluate the energy performance of the case study building in comparison with different glass types used in retrofitted cases. From an economic perspective, the internal rate of return (IRR) and discounted payback periods (DPP) were used as determining indexes. The results demonstrated that retrofitted windows with the best energy-efficient glass might achieve energy performance, but installation cost can reduce economic feasibility, while the glass with the second lowest heat transfer coefficient can reduce the OTTV by 68.89% and building energy consumption by 16.87%. However, it can achieve the highest economic performance with 10.70% IRR and DPP at 11.83 years. Therefore, the balance between energy and economic factors must be considered to provide energy-efficient and investment-friendly glass materials for retrofit projects. In addition, the study focuses specifically on tropical climates. Thus, the finding may not be reflected similarly for buildings located in different regions.

Thermal performance of concrete masonry units containing insulation and phase change material

The stationary thermal performance requirements of building energy codes are mainly met by compounding insulation materials in building envelope or adding air interlayers. However, with the transformation of building envelope to lightweight and hollow, its thermal capacity value decreases significantly, which causes the indoor thermal environment to fluctuate with the outdoor space. The introduction of phase change materials is a potential solution to improve the transient performance. However, since the thermal properties of phase change materials vary with several environmental factors, it is a complex problem to rationalize the use of phase change materials, including their location in enclosures, the selection of types, quantities, and how to couple with insulation materials, so that the enclosures can achieve high stationary and transient performance simultaneously. In this study, a thermal environment simulator was built for the investigation of a series of triple concrete masonry unit blocks (bricks) equipped with insulation materials or/and phase change materials using dynamic testing method. The experiments were conducted under three typical boundary conditions reflecting different orientations of walls. A complete specification of the thermal performance of the walls with different configurations is summarized. It is found that the performance of insulation materials is stable, while the performance of phase change materials is influenced by the type and quantity of materials, indoor and outdoor temperatures, and the location in envelope. Phase change materials can show much higher thermal performance than insulation materials if under appropriate conditions. A series of construction optimization cases that can significantly improve the thermal performance of envelope are summarized, and general construction principles for envelopes with high thermal performance are given. From the influence laws of thermal performance to the improvement measures and the general rules of envelope configuration, this study provides the theoretical basis, optimization cases, and guidance rules for thermal applications of insulation-phase change building envelopes.

Is energy-efficient building sustainable? A case study on individual housing in Canada under BCESC energy updates

Life cycle thinking and holistic sustainability assessment are missing in current building energy codes globally, with primarily focus on operational energy use and greenhouse gas (GHG) emissions. The overall objective and originality of this study is to evaluate the building-level life-cycle environmental and economic impact of building energy code compliance, exploring the trade-offs between energy savings, various environmental impacts and cost effectiveness, taking the British Columbia Energy STEP Code (BCESC) as a case study. An integrated approach of using building information modeling (BIM) with whole building life cycle assessment (LCA) and life cycle costing (LCC) is proposed, and comparisons of life cycle environmental and economic impacts are studied with respect to each energy upgrade level. The findings revealed that while the total energy demand intensity and GHG emissions decreased (by about 50% compared to base scenario) with the code intervention steps, the other environmental impacts may increase due to the embodied materials, production, and upkeep of the upgrades, for example, the ozone depletion potential increased by nearly 800% compared to the baseline. Additionally, the energy-saving measures reduce building operating costs by about C$4,000, which is significantly less than the increased costs in other stages. However, this incremental cost does not always mitigate the effects of specific environmental impact categories. The findings will be of interest to building industry policymakers to develop more holistically sustainable building energy policies, allocating limited funds in a more cost-effective manner to reduce environmental impacts, instead of focusing solely on direct and temporary benefits.

Methods in open policy analysis: An application to California's building energy codes

AbstractHave building energy codes lowered energy consumption, and have their benefits outweighed costs? Using 2000 Census data, I estimate household energy expenditures by decade of home construction, controlling for household and home characteristics. I find homes built in the 1980s used $35 less in electricity and $46 less in natural gas, per year, compared to 1970s era homes. For Sacramento, energy codes pass a cost‐benefit test when low‐end policy costs are used, but fail with base‐case costs. This study also clarifies how a cost‐benefit analysis (CBA) for a representative household fits into a comprehensive CBA.