Keywords

1 Introduction

Globally building floor space has expanded 65% since 2000, while energy/m2 has improved by only 25% [1]. As per IEA, building energy codes set standards for the construction of buildings with better energy performance and are a proven method to reduce building energy consumption in buildings [2]. As of 2019, however, less than 75 countries have or are developing a mandatory or voluntary building energy code, and around 45% of those countries building codes cover just part of the buildings sector. Energy policy progress is not keeping pace with buildings sector growth []. Mandatory policies covered less than 40% of energy use and less than half of CO2 emissions from buildings in 2017 [1]. To be in line with the sustainable development scenario by 2030: all countries need to establish mandatory building energy codes; new high-performance construction needs to rise from current 275 million m2 to more than 5 million m2 by 2030, increasing code coverage and stringency [3].

The buildings sector’s share of the world’s delivered energy consumption increases from about 20% in 2018 to 22% in 2050. Building energy consumption in non-Organization for Economic Co-operation and Development (OECD) countries increases at about 2% per year, about five times faster than in OECD countries, and surpasses that of OECD countries by 2025 [4]. India comes under the category of non-OECD country. Electricity remains the fundamental source of marketed energy consumption in the residential sector, and its use grows by 2.5% per year globally [5]. India and China remain the fastest-growing region in residential sector energy consumption. China adds the most residential energy consumption of any country (in absolute terms), while India experiences the fastest relative growth in residential energy consumption from year 2018 to 2050 [5]. Studies on global changes in residential energy consumption recommend on promotion of direct and indirect renewable energies to reduce energy consumption and increase in adoption of energy code and practices.

Energy policies can be successful only if they are enhanced by making them mandatory, targeting net-zero energy building, and increasing public awareness about new technologies. Stricter regulations especially in existing buildings need to be further stressed by focusing on both new technology development and more educationally-related approaches to energy saving. In a recent study on building codes and implementation states that by better understanding in implementing building energy codes, policymakers can improve the effectiveness of their code implementation systems.

2 Background

Integrating the element of energy efficiency with building codes is a recognized strategy which aims to reduce energy consumption in the residential and commercial sectors. Globally, countries are independently establishing building codes and implementing energy efficiency policies, programs in residential and commercial segments to decrease energy waste in the new and existing building stock.

In many countries, the central government has authority to mandate energy efficiency in buildings by forming national building codes which are often adopted and implemented by state regions and/or local municipalities. Model energy code is developed by national code development organizations for review and adoption by state and local governments and is mandatory in nature. The practice of development of code, approval, and enforcement varies considerably among nations. Stakeholders have realized that energy codes are one of the simplest, most effective tools available to reduce building energy use.

As a building's operation and environmental impact is largely determined by upfront decisions by consumers, energy codes present a unique opportunity to assure savings through efficient building design, technologies, and construction practices. Once a building is constructed, it is suggestively more expensive to achieve higher energy efficiency levels. Energy codes ensure that the building's energy use is involved as a fundamental part of the design and construction process. Socioeconomic development (improvement of human comfort levels and entertainment activities), architectural design, geography, and climate data are the main factors underpinning the energy consumption trend in residential buildings.

Building codes seek to address common barriers to energy-efficient building design. Buildings regulation set of legal and mandatory requirements for building design and their compliance provisions during the construction period aiming at promoting energy performance of building. Building envelope consists of walls, roof, and fenestration (openings including windows, doors, vents, etc.). Design of building envelope influences heat gain/loss, natural ventilation, and daylighting, which, in turn, determines indoor temperatures, thermal comfort, and sensible cooling/heating demand. Since building codes set minimum requirements for energy efficiency in buildings, several countries have developed voluntary standards, encouraging sustainability, and higher energy efficiency buildings.

India took a step forward in late 2018, developing its first national model building energy code for residential buildings. The Energy Conservation Building Code for Residential Buildings is designed to be enforced simply while also improving occupant’s thermal comfort and enabling the use of passive systems [6]. Implementation of ENS will have the potential for energy savings to the tune of 125 billion units of electricity per year by 2030, which is equivalent to about 100 million ton of CO2 emission. The code sets minimum performance standards for building envelope to limit heat gains and limit heat loss through it, also for adequate natural ventilation and adequate daylight potential [6]. The situation with ECBC code under EC ACT 2001 is that till date, it remains voluntary code with no mandates in most of the states in India. ECBC-R also has the same challenges, that it might take years, before they become mandatory in most of states.

3 Methodology

Understanding code and its implementation requires a clear picture on what all code constitute and what does not. Also, it is required to understand the difference between various terminologies used like code, labels, standards, and rating system. Building codes are often mistaken as building energy labels and building standards. An energy label for building constitutes consumer information on the performance of a product (the building). A building rating system is a tool that evaluates the performance of a building and its impact on the environment [7]. It comprises a predefined set of criteria relating to the design, construction, and operations of buildings. Energy standards describe how buildings should be constructed to save energy cost-effectively [7].

The diversity in residential building energy code and implementation practice among different countries poses challenges for measuring building energy code implementation and impact. This paper covers a systematic review of building energy code and their implementation systems, analyzing building energy code in 12 countries across the world and recommends on the best practices. To compile the information needed regarding the code and current practices, the reviewed literature has been accessed from data available over government websites and global networks. The key categories have been defined initially for data collection, namely code coverage, code implementation, revision and incentive structure, building material and certification and then processed further. In addition, a number of countries have implemented programs to evaluate the effectiveness of building energy code.

3.1 Review on Global Approaches

Building energy code tends to set minimum energy efficiency levels, but these energy savings are never realized unless states and localities implement them. This section highlights the comprehensive review of building codes and its implementation across all 12 countries. Figure 77.1 displays the timeline of year of code adoption among these countries. It showcases two versions: Current and earlier. The current versions are the revised or currently opted versions in the respective country. Earlier versions are previous versions which were implemented but not in order now.

Fig. 77.1
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Timeline of code adoption

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India launched their residential energy code in late 2018, although for commercial buildings the code into picture in 2007. Developed countries have opted the code in earlier years and they have also released the revised versions.

3.2 Code Coverage

The first step in ensuring that building energy efficiency requirements apply to a significant part of buildings and have an impact on energy-intensive buildings is code coverage. Countries may have varied practices when it comes to what a code covers. Depending on the country, the code shall only apply to definite types or size of buildings; it may cover a comprehensive range of energy uses or only the building envelope. It may or may not apply to planned renovations. It is also important to note that code coverage is one way to consider the scope of implementation. Table 77.1 reflects code coverage for different countries with in depth information.

Table 77.1 Global outlook on code coverage
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It can be observed that Italy, USA, Australia and China have not defined any building size threshold for new and existing buildings in their code. Australia, Singapore, Spain, and Turkey have threshold limits defined for renovations. Australia, China, France, Germany, Italy, South Korea, Spain, United Kingdom, and USA have included of renewable energy as a parameter in over all measures covered for building. In Turkey, buildings larger than 20,000 m2 must use renewable energy. Most of the countries have made mandatory for their states to adopt the code.

3.3 Code Adoption

Implementation of energy code is generally approved by state and local bodies that are responsible for code compliance, enforcement, and training. This process ensures that new construction attains the required level of efficiency. Australia, Canada, China, India, Italy, and USA follows three-tier government system: National government develops the code, adopts national code to state requirements, and the local jurisdiction contributes in enforcing the code. For France, Germany, Singapore, South Korea, Turkey, and UK, the central government develops and adopts the code and the local jurisdiction contributes in enforcing the code. Enforcement may occur at both the design and during construction. At the design phase, an enforcement agency shall verify that plan for the building meets the specified energy efficiency requirements, while at the construction part, the code official or third party checks that construction matches with the code compliance. The built changes may also go through design review and on-site inspections. Compliance checks are divided into three phases: design, construction, and pre-occupancy checks. Australia, Canada, China, France, Germany, Italy, Singapore, USA have developed code compliance resource kits. There are training programme and tools in several countries to enable implementation of building energy code. India has launched a compliance tool for ECBC-R for evaluation and reporting. Table 77.2 reflects code adoption for different countries.

Table 77.2 Code adoption
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3.4 Revision Schedule, Incentives and Penalties

Code revision may demand innovation that creates better products and encourages economic development. State and local building codes need to keep up with ongoing innovations in building energy, science, and technology. Some code developers push for a six-year code cycle and some for three. Incentives and penalties in the code ensure that the interests of stakeholders are aligned with the desired policy outcome, such as code implementation. Conventionally, central and state governments employ penalties, to achieve compliance. For India: Penalties for non-compliance with energy provisions in codes are decided at the state level. Currently, no state has penalties for non-compliance. Various countries offer exemptions on tax and low-interest rate on implementation of codes. India has no incentive scheme, although there are various rating programme which offer state wise incentives. Table 77.3 reflects information about code revision, incentives and penalties.

Table 77.3 Code revision, incentives, and penalties
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3.5 Building Material and Certification

Building materials with labels evidently state that they are tested for energy performance properties. Code officials may easily verify that materials are aligned with the code-compliant design or not, or if tested and labeled materials are being used. Thus, having a method for testing, rating, and labeling properties of the materials makes it easier for all stakeholders to ensure buildings are made from high-performance products. Except Australia, Italy, and India, all other countries have a mandatory provision for testing, rating and labeling building materials. Canada and India have voluntary based certification system. Turkey initially required certification on thermal insulation which is separate from building performance certification. Australia, USA, and China have building energy code evaluation programs. Table 77.4 reflects information about building materials and certification.

Table 77.4 Building material and certification
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4 Conclusion

There are numerous ways to assess the effectiveness of energy efficiency building codes globally, and this paper aims to give an overview of 12 countries and five elements of building energy code or review. There are many polices that were not included in this paper, such as building labeling, retrofit policies, commercial codes, and other mechanisms. However, based on the current parameters analyzed, countries that are leading the way with respect to the overall effectiveness of residential codes are USA, France, China, and Australia. This study analyzed country-specific information: Code coverage, code adoption, revision schedule, code compliance, penalties, incentives for implementation, building material, and energy certification. Most of the countries have made mandatory for their states to adopt the code. India follows voluntary code system. Penalties for non-compliance of the codes are decided at the state level in India. Currently, no state has penalties for non-compliance. Most of the countries deny on construction permits as a penalty. Australia, Canada, China, India, Italy, and USA follow three-tier government system: National government develops the code, adopts national code to state requirements, and the local jurisdiction contributes in enforcing the code. Australia, Canada, China, France, Germany, Italy, Singapore, USA have developed code compliance resource kits. India has launched a compliance tool for ECBC-R for evaluation and reporting. It provides a comprehensive summary of compliance status of all the mandatory compliance criteria of the code, for the proposed design.

This research highlights the importance of code, its components and implementation mechanism. By better understanding the range of practices in implementing building energy code, policymakers can improve the effectiveness of their code implementation systems.