Green Building Standards and Certification Systems  

by Stephanie Vierra, Assoc. AIA, LEED AP BD+C
Vierra Design & Education Services, LLC



Buildings have extensive direct and indirect impacts on the environment. During their construction, occupancy, renovation, repurposing, and demolition, buildings use energy, water, and raw materials, generate waste, and emit potentially harmful atmospheric emissions. These facts prompted the creation of green building standards, certifications, and rating systems aimed at mitigating the impact of buildings on the natural environment through sustainable design.

The push toward sustainable design increased with the launch of Building Research Establishment's Environmental Assessment Method (BREEAM), the first green building rating system in the world. The U.S. Green Building Council (USGBC) followed suit and developed and released criteria also aimed at improving the environmental performance of buildings through its Leadership in Energy and Environmental Design (LEED) rating system for new construction. LEED has continued to grow in prominence and now includes rating systems for existing buildings, interiors, and entire neighborhoods. Others also responded to the growing interest and demand for sustainable design including the Green Building Initiative (GBI), which was created to assist the National Association of Homebuilders (NAHB) in promoting its Green Building Guidelines for Residential Structures. Originally developed for Canada, GBI helped to make Green Globes available for use in the U.S. Additional rating systems have been developed that were influenced by these early programs but are tailored to their own national priorities and requirements or seek to go beyond the limits of current policy and building practices to address broader issues of sustainability such as net zero energy, living, regenerative, and restorative building concepts that improve the natural environment, or those that model nature's processes.

Green product standards have been in the marketplace since the 1980s and continue to increase in scope and number. Initially, many green product standards were developed in response to growing concerns for product toxicity and its impact on children's health and indoor environmental quality (IEQ). Today, when growing concerns over climate change and resource depletion are more prominent and supported by research, the number and type of green product standards and certifications continue to grow. The focus has also expanded to include a broader range of environmental issues and the impacts of products during their manufacture, use, and reuse. While there is still no universal definition of a green product, these products are intended to meet claims that they offer environmental benefits and adhere to certain standards. (See also Optimize Building Space and Material Use)

There is a proliferation of standards, rating, and certification programs in the marketplace to help guide, demonstrate, and document efforts to deliver sustainable, high-performance buildings. There are hundreds of green product certifications in the world, many in use in the U.S., and the numbers continue to grow (Source: BuildingGreen). There are also green building rating programs in use around the world and they vary in their approach with some outlining prerequisites and optional credits, while others take a prescriptive approach, and still others suggest performance-based requirements that can be met in different ways for different products and project types. As a result, it can be challenging and time consuming determining which standards, certifications, and rating programs are most credible and applicable to a particular project. This page provides an introduction to some commonly used terms and an overview of the most widely recognized green building product standards, and building rating and certification programs currently in use with an emphasis on how they vary and some of the issues to consider when selecting them.

left: David L. Lawrence Convention Center, Pittsburgh; right: one-story building converted into an office building

Green building design strategies are being applied across a very diverse range of projects from office buildings to schools, stadiums, hospitals, and entire neighborhoods. Left: The David L. Lawrence Convention Center in Pittsburgh was one of the first major buildings to achieve LEED certification, earning LEED Gold. Photo Credit: VISITPITTSBURGH. Right: A one-story building converted into an office building that achieved Living Building Challenge Certification.
Photo Courtesy of Arch Nexus


A. Building Standards

A standard is a set of guidelines and criteria against which a product can be judged. Common standards related to building practices are created through consensus processes by organizations such as ANSI, ASTM, or ASHRAE. Supporting the governance of standards and certifications is the International Standards Organization (ISO), which defines and develops worldwide standards that frequently become law or form the basis of industry norms. ISO defines a standard as: "a document, established by consensus, approved by a recognized body that provides for common and repeated use as rules, guidelines, or characteristics for activities or their results."

Requirements found in standards may either be prescriptive (identifying methods of achievement) or performance based (stating expectations of end results). Consensus based standards, those developed through a formal, voluntary consensus process that is exemplified by an open and due process have immediate buy-in, government support, and international influence. According to the National Technology Transfer and Advancement Act (NTTAA) federal agencies are required by law to adopt existing private-sector voluntary consensus standards instead of creating proprietary, non-consensus standards. Standards frequently serve as incentives for improved performance. Many of the green product standards available today are proprietary or regulatory standards that have been developed outside of the formal ANSI and ISO consensus process. These types of standards may be more or less stringent than consensus standards and can include some level of transparency and public comment. However, many of these types of standards are trusted because they are associated with a group that has strong environmental credentials.

The ANSI/ASHRAE/USGBC/IES Standard 189.1-2017, Standard for the Design of High Performance Green Buildings except Low-Rise Residential Buildings provides minimum requirements for site, design, construction and operations in mandatory, code-enforceable language. This standard is comprehensive and includes chapters for site, water, energy efficiency, indoor environmental quality, and materials. For a detailed description on many other building codes and standards that address sustainability goals and requirements, see the Relevant Codes and Standards section below and Energy Codes and Standards.

B. Green Codes

Green building codes continue to be developed and adopted in the U.S. and abroad that seek to push the standard of building design and construction to new levels of sustainability and performance. Codes come in two basic formats: prescriptive and performance, with outcome-based becoming a developing third option. A Prescriptive path is a fast, definitive, and conservative approach to code compliance. Materials and equipment must meet a certain levels of stringency, which are quantified in tables. Performance-based codes are designed to achieve particular results, rather than meeting prescribed requirements for individual building components. Outcome-based codes for example, establish a target energy use level and provide for measurement and reporting of energy use to assure that the completed building performs at the established level. (See also: Outcome-Based Pathways for Achieving Energy Performance Goals.)

The unique difference between codes and building rating systems is that codes are mandatory. As green codes become adopted on a wide spread basis, their impact will change the building environment rapidly and extensively. When undertaking a project, whether it is new construction or a renovation, check to see if there is a state or local green code that will dictate the direction and scope your project must take.

The International Green Construction Code (IgCC) provides a comprehensive set of requirements intended to reduce the negative impact of buildings on the natural environment. It is a document which can be readily used by manufacturers, design professionals and contractors; but what sets it apart in the world of green building is that it was created with the intent to be administered by code officials and adopted by governmental units at any level as a tool to drive green building beyond the market segment that has been transformed by voluntary rating systems.

It was developed by the International Code Council (ICC) in association with cooperating sponsors ASTM International (ASTM) and the American Institute of Architects (AIA). Other organizations indicating their support include the U.S. Green Building Council (USGBC), and The Green Building Initiative (The GBI), producers of the Green Globes rating system. The IgCC was developed with the intent to be consistent and coordinated with the ICC family of Codes & Standards: the I-Codes. It is applicable to the construction of high performance commercial buildings, structures, and systems, including existing buildings subject to alterations and additions, utilizing both traditional and innovative construction practices. Residential occupancies are covered by reference to the ICC 700 National Green Building Standard (NGBS). High-rise residential buildings, however, may conform to either the IgCC or ICC 700. The IgCC also allows jurisdictions to choose ANSI/ASHRAE/USGBC IES Standard 189.1 as jurisdictional compliance option. ASHRAE Standard 189.1-2017, Standard for High-Performance Green Buildings Except Low-Rise Residential Buildings, is an American National Standards Institute (ANSI) standard developed by the American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE) in association with the Illuminating Engineering Society (IES) and the U.S. Green Building Council (USGBC). Because it was written in mandatory language, the IgCC is poised to produce environmental benefits on a massive scale: a scale impossible to attain with purely voluntary green building programs and rating systems.

The California Green Building Standards Code (CALGreen Code)  is Part 11 of the California Building Standards Code and was the first statewide "green" building code in the US. CAL Green is designed to save water and promote environmentally responsible, cost-effective, healthier places to live and work. The purpose of CALGreen is to improve public health, safety and general welfare by enhancing the design and construction of buildings through the use of building concepts having a reduced negative impact or positive environmental impact and encouraging sustainable construction practices in the following categories:

  • Planning and design
  • Energy efficiency
  • Water efficiency and conservation
  • Material conservation and resource efficiency
  • Environmental quality

C. Green Product Certifications

A certification is a confirmation that a product meets defined criteria of a standard. ISO defines certification as: "any activity concerned with determining directly or indirectly that relevant requirements are fulfilled."

Green product certifications are intended to outline and confirm that a product meets a particular standard and offers an environmental benefit. Many product labels and certification programs certify products based on life-cycle parameters, making them multi-attribute programs. These parameters include energy use, recycled content, and air and water emissions from manufacturing, disposal, and use. Others focus on a single attribute, such as water, energy, or chemical emissions that directly impact Indoor Environmental Quality (IEQ).

A green product certification is considered most respected when an independent third-party is responsible for conducting the product testing and awarding the certification. Third-party means they are independent of the product manufacturer, contractor, designer, and specifier. Third-party labels and green product certification programs can be helpful in evaluating the attributes of green products because they validate that the product meets certain industry-independent standards. They can also offer greater assurance to consumers, designers, specifiers, and others that a product's marketing claims accurately reflect its green attributes. Many product certifications are also recognized within comprehensive green building rating systems such as LEED, Green Globes, BREEAM, and the National Green Building Standard. As a result, green product certifications are on the rise as market conditions change and the demand for greener products continues to increase. It is important to note that greenwashing, which is defined as the use of green claims that are not true or are unverifiable but used to sell products or a corporate image, has become commonplace as companies try to stay competitive in the green marketplace. (See also Evaluating and Selecting Green Products.)

Exterior western view of the Brock Environmental Center

From windows and doors, to carpet, paints, and skylights, many more building products have achieved a sustainability rating from a third-party based on life-cycle parameters. The Brock Environmental Center achieved LEED Platinum and Living Building Certification and had full transparency of the materials, products, and systems used in the project.
Photo Prakash Patel Photography, courtesy of SmithGroupJJR

To fully understand what a green certification represents and the quality of information it provides, the details of its requirements need to be reviewed carefully. The ISO defines different types of labels that can be used for products. Below is an outline of the ISO-defined labels in the 14000 series and what is being claimed. Product certifications available in the U.S. are mostly Type I and Type II labels while Type III labels are now required in France and becoming more common in Europe and for those U.S. manufacturers with an international focus.

ISO-defined Types of Green Product Certification Labels

Type ISO Number What the label does
Type I ISO 14024 Seal of approval for multi-attribute requirements
Type II ISO 14021 Verifiable single-attribute environmental claims for issues such as energy consumption, emissions, or recycled content. Can be first-party, self-declared manufacturer claims. However many manufacturers are beginning to seek third-party verification of those claims in response to industry demand.
Type III ISO >14025 Comprehensive environmental product disclosure and detailed product information. Similar to an Environmental Product Declaration (EPD)

Summary of Green Product Certifications

The following table, and the expanded information directly below it, outlines some of the most commonly used and respected green product certifications in the marketplace. Please see the Additional Resources section for more information on other programs not included in this page.

Product Certification Single- or Multi-Attribute Type of Standard or Certification Managing Organization Issue of Focus
Energy Star Single-Attribute Government certification relying on manufacturer-provided data or third-party testing U.S. EPA and U.S. DOE Energy consuming products
WaterSense Single-Attribute Government label based on third-party testing U.S. EPA Showerheads, toilets, faucets, urinals, and valves
Forest Stewardship Council Single-Attribute Third-party certification Forest Stewardship Council (FSC) Forests and forestry products
SCS Global Services Multi-Attribute Third-party certification SCS Global Services Wide range of products ( i.e. carpets, textiles, wood products, insulation, and more)
Green Seal Multi-Attribute Third-party ISO Type 1 certification Green Seal Wide range of sectors (paints, adhesives, lamps, electric chillers, windows, window films, occupancy sensors)
Cradle to Cradle Multi-Attribute Third-party certification, Cradle to Cradle CertifiedCM Product Standard is managed and updated by the Institute’s Certification Standards Board Cradle to Cradle Products Innovation Institute C2CPII Building materials, interior design products, textiles and fabrics, paper and packaging, and personal and homecare products
GREENGUARD Multi-attribute Third-party certification UL Environment Indoor air quality, children and schools focus
Green Squared Multi-attribute Third-party ISO Type 1 environmental labeling and declaration requirements (ISO 14024) TCNA Tiles and tile installations
International Green Mark (IGM) Single and Multi-Attribute ISO 17065 and ISO 17067 The GORD Institute Various building products including wood, sealants, paints, concrete, and more
Natural Stone Sustainability Standard (ANSI 373) Multi-attribute Independent consensus-based standard Natural Stone Institute and NSF International Natural stone production

Single-Attribute Product Certifications

energy star logo

ENERGY STAR—First established as a voluntary labeling program, Energy Star is a widely recognized government-run product certification label for energy efficient products. It is a joint program of the U.S. EPA and DOE. Energy Star-certified products include appliances, heating and cooling equipment, lighting, home electronics, commercial roofing, and office equipment. Energy Star standards are generally updated and made more stringent every two years. (See also Single-Attribute Building Rating System below.)

The Energy Policy Act of 2005 (EPACT) requires federal agencies to buy either Energy Star products or products designated as energy efficient by the Federal Energy Management Program (FEMP), for which the requirements are included in the Federal Acquisition Regulation (FAR) Subpart 23.203. Executive Order 13423 requires federal agencies to activate Energy Star "sleep" features on computers and monitors and mandates that federal agencies buy EPEAT* registered products. (For more information addressing federal requirements for Energy Star, click here)

epa watersense logo

WaterSense—A partnership program by the U.S. EPA, WaterSense seeks to protect the future of our nation's water supply by offering people a simple way to use less water with water-efficient products, new homes, and services. Established for water-efficient products, the program seeks to help consumers make smart water choices that save money and maintain high environmental standards without compromising performance. WaterSense products and services that have earned the label must be at least 20 percent more efficient without sacrificing performance. Look for the "WaterSense: Meets EPA Criteria" label, not just "WaterSense Partner". The "partner" label indicates that an organization or manufacturer has signed an agreement with EPA to promote water efficiency but does not address performance of a specific product.

Executive Order 13423 requires federal agencies to implement water-efficiency measures, including the purchase, installation, and implementation of water-efficient products and practices. Agencies must reduce water consumption intensity, relative to their fiscal year baseline, through cost-effective life-cycle measures by 2 percent annually (or 16 percent total).

forest stewardship council logo

Forest Stewardship Council (FSC)—A third-party certification program established with the goal of promoting responsible forestry and certifying the resulting wood products. The standard is managed by the FSC while certification is awarded by third parties such as the Rainforest Alliance and Scientific Certification Systems. There are different standards for different forest products (FSC pure, FSC mixed, and FSC recycled) and different regions. The FSC chain of custody is a requirement of certification that follows the path of the wood product from forest to consumer. The FSC program uses a specific, prescriptive approach and provides assurance of good environmental and social stewardship of forests.

scs global services logo

SCS Global Services—A third-party certification of claims for recycled content, biodegradable liquid products, and no-added formaldehyde products. SCS Global Services is a long-respected certifier that backs its certifications with vigorous and transparent standards. A number of products with this certification meet indoor air quality, recycled content, and FSC chain-of-custody requirements within green building rating systems including LEED, Living Building Challenge, and Green Globes.

Multi-Attribute Product Certifications


green seal logo

Green Seal—A third-party certification and labeling program that covers a wide range of products with sector-specific requirements, particularly consumable items for building operations and maintenance. Green Seal has been certifying products for many years and is an ISO 14020/14024 standards and Global Ecolabelling Network's Internationally Coordinated Ecolabelling System (GENICES). Green Seal considers the impacts of a product over its entire life cycle when developing a standard. Building products covered include paints, adhesives, lamps, electric chillers, windows, window films, and occupancy sensors. Green Seal is referenced in several LEED rating systems, and cleaning products for industrial and institutional use are referenced in LEED for Existing Buildings in Operations and Maintenance. They have also partnered with the WELL Building Standard, the Health Product Declaration Collaborative, and others tohelp align the cleaning services standards with these program requirements. Healthy Green Hotels and Healthy Green Schools are among their important programs.

cradle-to-cradle logo

The Cradle to Cradle CertifiedCM—A third-party, multi-attribute eco-label administered by the Cradle to Cradle Products Innovation Institute that assesses a product's safety to humans and the environment and design for future life cycles. The program provides guidelines to help businesses implement the Cradle to Cradle framework, which focuses on using safe materials that can be disassembled and recycled as technical nutrients or composted as biological nutrients. Unlike single-attribute eco-labels, the Cradle to Cradle Certified program takes a comprehensive approach to evaluating the design of a product and the practices employed in manufacturing the product. The materials and manufacturing practices of each product are assessed in five criteria categories: Product Circularity, Clean Air and Climate Protection, Water and Soil Stewardship, and Social Fairness.

greenguard logo

GREENGUARD Certification Program—A third-party certification and label established in 2001 (formerly known as GREENGUARD Indoor Air Quality Certification). GREENGUARD Children and Schools certification complies with California Section 01350, calling for emissions at half of California's more stringent thresholds. GREENGUARD certifies that a product meets thresholds for formaldehyde, total aldehydes, total volatile organic compounds (VOCs), and one-tenth of the threshold limit value (a regulatory benchmark) for many other compounds. The GREENGUARD Environmental Institute certifies products that comply with their rigorous formaldehyde, emissions, and chemical testing requirements.

green squared logo

Green Squared—Certification was developed by TCNA, and involves one industry, one standard, and one mark, and covers products used in a tile installation. As the first multi-attribute sustainability standard developed for tiles and tile installation materials, Green Squared uses the transparency and consensus of the ANSI process combined with third-party certification to evaluate, validate, and communicate products which have a positive impact on the environment and society. Green Squared covers product characteristics, manufacturing, end of product life management, progressive corporate governance, and innovation in an effort to establish sustainability criteria for products throughout their full life cycle. Green Squared acknowledges products which have been verified to be in conformance with ANSI A138.1. The easily-recognizable Green Squared mark helps architects, designers, and end users choose products and assured that the products they are choosing meet the industry's broad range of sustainability criteria. These products are accepted within LEED, IgCC, NAHB's Green Building Standard, and Green Globes.

international green mark

International Green Mark (IGM)—An environmental labelling system created by the Gulf Organisation for Research & Development (GORD) which offers a robust and independent eco-labeled products certification process to manufacturers and suppliers to ensure that IGM eco-labeled products deliver high environmental performance and quality. By assessing and verifying the sustainable attributes of products, IGM presents an impartial statement on whether a product is less harmful to the environment than another similar yet unlabeled product. IGM schemes follow the requirements of ISO 17065 and ISO 17067. IGM is operated by the GORD Institute, a Centre of Excellence at GORD.

natural stone

Natural Stone Sustainability Standard (ANSI 373)—The Standard examines and verifies numerous areas of natural stone production; effectively improving the baseline for the environmental performance of natural stone at the quarrying and fabrication stages of the process. The metrics used to define sustainable production in the dimension stone industry include energy/carbon, land impacts, ingredient transparency, social responsibility, chain of custody, and more. Certification is awarded at the Bronze, Silver, Gold, and Platinum Levels. Points for using certified natural stone quarries and fabrication facilities are achievable within LEED and the Living Building Challenge through the use of this Standard. EPD and HPD labels for natural stone are also available.

Another category and approach to identifying and declaring the manufacturing, production, ingredients and make up of a product is also growing. Whether it is an Environmental Product Declaration (EPD), a Health Product Declaration (HPD), a Declare Label, or the Living Product Challenge, there is a growing movement to seek full disclosure of a product within a life cycle framework and create a world of products that do no harm and improve the environment. Additionally, the JUST Label seeks to address social responsibility through transparency. These labels are starting to be accepted or required within the various green building rating systems, although labels do not yet exist for all products. For example, in LEED there is an option within the Materials and Resources category to achieve credits for transparency about the environmental life-cycle impacts of a product by utilizing an EPD. The Declare label is in use within the Living Building Challenge to meet the stringent materials requirements.

environmental product declaration (EPD) logo

An Environmental Product Declaration (EPD) is an independently verified and registered document that communicates transparent and comparable information about the life-cycle environmental impact of products. The International EPD System is a global program for environmental declarations based on ISO 14025, TS/14027, 14040, and EN 15804. Their database currently contains more than 500 EPDs registered by 150 companies in 27 countries. Having an EPD for a product does not imply that the declared product is environmentally superior to alternatives. It is simply a transparent declaration of the life-cycle environmental impact. The relevant standard for Environmental Product Declarations is ISO 14025, where they are referred to as "type III environmental declarations". A type III environmental declaration is created and registered in the framework of a program, such as the International EPD System. An EPD may be used for many different applications, including green public procurement (GPP) and building assessment schemes. For example, within LEED, BREEAM, and other international green building rating systems, EPDs are used to encourage the purchasing of low carbon products with life-cycle information. See: for more information.

health product declarations (HPD) logo

Designers, specifiers, and owners are increasingly seeking transparent information on the ingredients in building products, and their associated health hazards. Health Product Declarations (HPD) provide a full disclosure of the potential chemicals of concern in products by comparing product ingredients to a wide variety of "hazard" lists published by government authorities and scientific associations. To achieve third-party verification, the HPD must have 100% disclosure of known ingredients and/or 100% disclosure of known hazards down to 1000 ppm. The Health Product Declaration (HPD) Open Standard consists of a defined Format and Instructions for reporting about the contents of building products along with the associated health and other related information. The Standard is maintained and sponsored by the Health Product Declaration Collaborative. Version 2.2 of the HPD Open Standard became effective in May 2020. All versions of the HPD are recognized within LEED v4 Material Ingredient credits. Within LEED v4.1 Materials and Resources credit: Building Product Disclosure and Optimization: Material Ingredients, HPDs can contribute to earning points as well. For more information see the The Health Product Declaration® Collaborative (HPDC).

declare product page

Human and environmental health considerations have emerged as a crucial factor in material selection. Declare is a platform for manufacturers of ecologically sound products to demonstrate market leadership and secure a competitive advantage. Declare takes complex chemical analysis and raw material source location information and provides it to consumers in an elegant, easy to use 'nutrition label'. Declare gives manufacturers an expanded point of entry into the most groundbreaking restorative projects in the world. Project teams pursuing the Living Building Challenge can use the Declare product database and label to select products that meet the Living Building Challenge's stringent materials requirements, streamlining the materials specification and certification process to ensure that Declare products are free of chemicals on the Red List. Declare labels can also be used in LEED v4.1 in the Material Ingredient Reporting and Material Ingredient Optimization credit options. Additionally Declare Labels are in alignment with the WELL Building Standard. The Declare label is valid for a 12-month period. After this period, manufacturers must renew by paying a renewal fee and either confirm that the information contained within the Product Declaration Form has not changed or submit a new form. See: Living Future— Declare for more information.

living product challenge petal page

According to the International Living Future Institute, "The Living Product Challenge is a philosophy first, an advocacy tool second, and a certification program third. It is intended to guide the manufacturing of thousands of things people are surrounded by on a daily basis, and to give direction and support to those who make the goods that are used. Within the larger Living Future Challenge framework that covers the creation of Living Buildings, Communities and Food Systems, the Living Product Challenge focuses on manufactured goods. It is a unified tool for transformative thought, allowing a future to be envisioned that is Socially Just, Culturally Rich and Ecologically Restorative. The Living Product Challenge 2.0 is comprised of seven performance categories, or "Petals": Place, Water, Energy, Health and Happiness, Materials, Equity and Beauty. Petals are subdivided into a total of 20 Imperatives, each of which focuses on a specific sphere of influence. This compilation of Imperatives can be applied to almost every conceivable product, of any size, manufactured in any location—be it a new innovation or a reinvention of an existing item." Living products are informed by nature, using the principles of biomimicry and biophilia. They are made using processes powered only by renewable energy. They improve one's quality of life while also being beautiful and functional. For more information see: Living Product Challenge.

just product page

The International Living Future Institute's JUST program is a voluntary disclosure program and tool for all types and sizes of organizations. JUST is a call to social justice action. It is not a verification or certification program. Rather, the program provides an innovative transparency platform for organizations to reveal much about their operations, including how they treat their employees and where they make financial and community investments. In a similar fashion to the Living Building Challenge's Declare Program, the JUST 2.0 Program acts somewhat as a "nutrition label" for socially just and equitable organizations. This approach requires reporting on a range of organization-and employee-related indicators. Each of the indicator metrics asks for simple yet specific and measurable accountabilities in order for the organization to be recognized at a One, Two, or Three Star Level, which is then summarized elegantly on a label. Organizations can use the label on their website or marketing to demonstrate their commitments to these issues. JUST marks a new era of corporate transparency. See: About JUST for more information.

D. Green Building Rating and Certification Systems

Both standards and product certifications will play a role in determining the level of sustainability or performance of a product. However, each must be considered as part of a larger process, integrating them into the overall project goals to ensure the entire project is sustainable.

Green building rating or certification systems broaden the focus beyond the product to consider the project as a whole. Rating systems are a type of building certification system that rates or rewards relative levels of compliance or performance with specific environmental goals and requirements. Rating systems and certification systems are frequently used interchangeably.

Green building rating and certification systems require an integrated design process to create projects that are environmentally responsible and resource-efficient throughout a building's life-cycle: from siting to design, construction, operation, maintenance, renovation, and demolition. A few of these programs are single-attribute, focusing solely on water or energy, while others are multi-attribute addressing emissions, toxicity, and overall environmental performance in addition to water and energy. While the philosophy, approach, and certification method vary across these the systems, a common objective is that projects awarded or certified within these programs are designed to reduce the overall impact of the built environment on human health and the natural environment.

Green building rating systems exist to address every project type from single-family houses and commercial buildings to entire neighborhoods. There are rating systems available for new construction, which focus on decisions made in the planning and design process and actions taken through construction, as well as for existing buildings, which focus on operations and maintenance throughout the life of the building. A primary reason for the creation of rating systems is the need to more clearly define, implement, and measure green strategies and their outcomes and impacts. Architects are also looking for help translating the goals of sustainability into design criteria. Because these goals are based on an evaluation of environmental performance, there is also an implicit need to assess the expected performance of the design and judge its level of success at achieving the desired goals. Given the broad scope of the sustainability agenda, architects need a way to organize this long list of criteria for green design. Which are most important? How to compare dissimilar goals? How do sustainability goals support or enhance other project goals? Do they conflict?

Federal, state, and municipal agencies across the country including the General Services Administration (GSA), Department of Energy, Department of Health and Human Services, and the Environmental Protection Agency, continue to lead in incorporating energy efficiency and sustainability by following federal mandates and green building guidelines in the design, construction, and renovation of Federal facilities. Most states and many major cities have also incorporated green into their internal building requirements for new construction.

To determine which standard, certification, or rating system should be used, ask the following:

  • Who the organization is that is making the assessment?
  • Is it being done by a first-party, second-party, or third-party?

A first-party assessment is one that comes directly from an organization that is associated with the entity making the claim or who may benefit from the claim. A second-party assessment is performed by an interested party such as a trade association. A third-party assessment is conducted by an independent party that has no financial interest or ties to the outcome of the assessment.

According to RSMeans there are four principles that should be considered when evaluating a building rating or certification system:

  • Science-based — Results and decisions must be reproducible by others using the same standard.
  • Transparent — Standards and process for awarding the certification should be transparent and open for examination.
  • Objective — Certification body should be free of conflict.
  • Progressive — Standards should advance industry practices, not simply reward business as usual.

Why Pursue a Green Building Rating or Certification?

The reasons for pursuing a green building certification for a project are varied. Certification through any rating system provides verification of the green nature of the project, and can be a valuable educational and marketing tool for owners and design and construction teams through the process of creating a more sustainable building. Green building certification also provides incentives for clients, owners, designers, and users to develop and promote highly sustainable construction practices. It is important to note that a building does not have to be certified to be sustainable and well-built.

The guidelines within rating systems also help to clarify a market filled with "green" options. Rating systems also clearly outline what green standards need to be followed and what types of green products should be included in construction specifications.

Ultimately, the type of certification system pursued for a project depends upon that singular project; none of these certification systems are one-size-fits all. The dynamic nature of projects might prohibit one system but favor another. The choice is dependent upon the uniqueness of each project and the project needs and requirements such as the project location, size, budget, and overall project goals. Also comparing essential issues such as cost, ease of use, and building performance will help determine which building rating system is applicable and which certification level is possible.

Building rating and certification systems are in a state of change and evolution and continue to be refined to reflect new standards and goals for achieving ever higher levels of sustainability. So it is essential to investigate the most current versions of these programs to gain an understanding of particular requirements that must be met in order to achieve the best results.

Benefits of Using Green Building Standards and Certification Systems

There are a wide range of economic and environmental benefits to sustainable design, often achieved through the use of standards, rating, and certification systems. According to a study of LEED certified buildings , the USGBC has found that energy, carbon, water, and waste can be reduced, resulting in savings of 30 to 97% respectively. Operating costs of green buildings can also be reduced by 8–9% while increasing in value up to 7.5%. Many sustainable buildings have also seen increases of up to 6.6% on return on investment, 3.5% increases in occupancy, and rent increases of 3%. Other benefits of green buildings, such as higher productivity and increased occupant health, have been attributed to better indoor environmental quality, increases in natural daylighting, and healthier materials and products within green buildings.

In a similar study by the GSA , 12 sustainable buildings that were analyzed from a whole building perspective cost less to operate, have excellent energy performance, and have occupants that are more satisfied with the overall building than the occupants in typical commercial buildings. The 12 GSA buildings were compared to industry standard performance of energy, water, maintenance and operations, waste, recycling, transportation, and occupant satisfaction metrics.

While these benefits are possible, it is important to note that they are dependent upon factors such as climate, topography, timing, credit synergies, and local building standards.

Summary of Green Building Rating and Certification Systems

The following table and the expanded information directly below it outlines several of the most commonly used and respected green building rating and certification systems in the U.S. marketplace.

Building Rating or Certification System Single- or Multi- Attribute Type of Standard or Certification Managing Organization Issues / Areas of Focus
Building Research Establishment Environmental Assessment Method (BREEAM) Multi-Attribute Green building rating and certification system through on-site independent third-party verification for:
  • New Construction
  • In-Use
  • Refurbishment & Fit Out
  • Communities


BRE Global Performance in:
  • Energy
  • Health & Well-being
  • Transport
  • Water
  • Materials
  • Waste
  • Land Use & Ecology
  • Management
  • Pollution

No prerequisites for In-Use

Leadership in Energy and Environmental Design (LEED) Multi-Attribute Green building rating and certification system through independent third-party verification for:
  • New Construction (NC)
  • Existing Buildings, Operations & Maintenance (EB O&M)
  • Commercial Interiors (CI)
  • Core & Shell (CS)
  • Schools (SCH)
  • Retail
  • Healthcare (HC)
  • Residential
  • Cities and Communities
U.S. Green Building Council Performance in:
  • Sustainable Sites
  • Water Efficiency
  • Integrative Process
  • Location & Transporation
  • Energy & Atmosphere
  • Materials & Resources
  • Indoor Environmental Quality
  • Innovation
  • Regional Priority
Green Globes Multi-Attribute Green building guidance and assessment program for:
  • Existing buildings
  • New construction
Green Building Initiative in the U.S.
BOMA Canada
Environmental assessment areas to earn credits in:
  • Energy
  • Indoor Environment
  • Site
  • Water Efficiency
  • Materials
  • Project Management

No prerequisites

Living Building Challenge Multi-Attribute Performance-based standard, and certification program for:
  • Landscape and infrastructure projects
  • Partial renovations and complete building renewals
  • New building construction
  • Neighborhood, campus and community design
International Living Future Institute Performance areas include:
  • Place
  • Water
  • Energy
  • Materials
  • Health & Happiness
  • Equity
  • Beauty

All areas are requirements.

Passive House Institute US Multi-Attribute Performance based passive building standard
  • Third-party RESNET approved quality assurance/quality control
  • Earns U.S. DOE Zero Energy Ready Home status
  • Includes HERS rating
Passive House Institute US Any type of building.

New focus areas include:
  • air tightness requirements
  • source energy limit
  • space conditioning criteria
  • net zero energy
    SITES Multi-Attribute Third-party verified rating system for development projects located on sites with or without buildings including:
    • Open spaces
    • Streetscapes and plazas
    • Commercial
    • Residential
    • Educational/Institutional
    Administered by GBCI Performance criteria in the areas of:
    • Site Context
    • Water
    • Soil & Vegetation
    • Human Health & Well-being
    • Materials Selection, and more
    WELL Building Standard Multi-Attribute Performance based standard and certification program for:
    • New and Existing Buildings
    • New and Existing Interiors
    • Core and Shell Retail
    • Retail
    • Education Facilities
    • Restaurant
    • Commercial Kitchen
    • Multifamily Residential
    Administered by the International WELL Building Institute™ (IWBI) Measures attributes of buildings that impact occupant health by looking at ten factors: Air, Water, Nourishment, Light, Movement, Thermal Comfort, Sound, Materials, Mind, Community, and Innovation.
    Fitwel Multi-Attribute
    • New Construction
    • Existing Buildings
    Center for Active Design Fitwel's seven health impact categories are: Impacts Surrounding Community Health, Reduces Morbidity and Absenteeism, Supports Social Equity for Vulnerable Populations, Instills Feelings of Well-Being, Enhances Access to Healthy Foods, Promotes Occupant Safety, and Increases Physical Activity
    International Programs
    BCA Green Mark Scheme
    Multi-Attribute Benchmarking scheme that aims to achieve a sustainable built environment by incorporating best practices in environmental design and construction, and the adoption of green building technologies. Building and Construction Authority (BCA) Rates buildings according to five key criteria:
    • Energy efficiency
    • Water efficiency
    • Environmental protection
    • Indoor environmental quality, and
    • Other green and innovative features that contribute to better building performance.
    (Hong Kong)
    Multi-Attribute Comprehensive standard and supporting process covering all building types, including mixed use complexes, both new and existing to assess, improve, certify, and label the environmental performance of buildings Business Environment Council Performance and assessment in:
    • Site aspects
    • Material aspects
    • Water use
    • Energy use
    • Indoor environmental quality
    • Innovations and additions
    Multi-Attribute Building assessment tools for
    • Pre-design
    • New Construction
    • Existing Building and
    • Renovation
    JSBC (Japan Sustainable Building Consortium) and its affiliated sub-committees Assessment areas include:
    • Energy efficiency
    • Resource efficiency
    • Local environment, and
    • Indoor environment
    EDGE Multi-Attribute A universal standard and a certification system for residential and commercial structures. International Finance Corporation (IFC), a member of the World Bank Group Assessment areas include:
    • Energy
    • Water
    • Materials
    Global Sustainability Assessment System (Middle East and North Africa) Multi-Attribute An integrated and performance-based rating system for buildings and infrastructure GSAS Trust Assessment areas include:
    • Urban Connectivity
    • Site
    • Energy
    • Water
    • Materials
    • Cultural & Economic Values
    • Management & Operations
    • Indoor Environment
    Green Star SA
    (South Africa)
    Multi-Attribute Green building rating system for:
    • Office
    • Retail
    • Multi-unit residential
    Green Building Council of South Africa administers program
    Independent assessors to assess and score projects
    Categories assessed in:
    • Management
    • Indoor Environmental Quality
    • Energy
    • Transport
    • Water
    • Materials
    • Land Use & Ecology
    • Emissions
    • Innovation
    Pearl Rating System for Estidama
    Multi-Attribute Green building rating system for:
    • Community
    • Buildings
    • Villas
    • Temporary Villas and Buildings
    Abu Dhabi Urban Planning Council Assessment of performance in:
    • Integrated Development Process
    • Natural Systems
    • Livable Communities
    • Precious Water
    • Resourceful Energy
    • Stewarding Materials
    • Innovating Practice

    Single-Attribute Green Building Rating Systems


    energy star logo

    Energy Star Rating System—is a rating system created by the U.S. EPA and DOE that uses a benchmarking method to assess a building's energy and water use. (Please note that Energy Star also has a product certification program. (See also Single-Attribute Product Certification above.)

    ENERGY STAR states that, "statistically representative models are used to compare your building against similar buildings from a national survey conducted by the Department of Energy's Energy Information Administration. This national survey, known as the Commercial Building Energy Consumption Survey (CBECS), is conducted every four years, and gathers data on building characteristics and energy use from thousands of buildings across the United States. Your building's peer group of comparison are those buildings in the CBECS survey that have similar building and operating characteristics. A rating of 50 indicates that the building, from an energy consumption standpoint, performs better than 50% of all similar buildings nationwide, while a rating of 75 indicates that the building performs better than 75% of all similar buildings nationwide." Keep in mind that certification is given on an annual basis and must be verified by a professional engineer or registered architect.

    To receive an Energy Star rating for a New Home, Home Improvement, or Business, a project's energy usage must be tracked with the online Portfolio Manager and receive a score of 75 or more.

    Multi-Attribute Green Building Rating Systems

    Outlined below are the building rating systems most commonly in use within the U.S. in the private and public sectors. Additionally, international programs are included to provide a reference point for those developing projects outside the U.S. These programs are always in a state of evolution and change, responding to market trends and demands, owners, users, and influencers in the green building arena. Before starting any project, a review of the project goals in conjunction with the intent and requirements of each rating system will help determine which is the most appropriate rating system to utilize. There are differences to the various programs including costs, standards that apply, points (full or partial) that can be achieved, life-cycle assessment use, and variations in ongoing evaluation and documentation required, among many others.

    breeam logo

    BREEAM was launched by BRE (Building Research Establishment), a world leading, multidisciplinary building science organization. BREEAM was the world's first environmental assessment method for buildings and is defined by building science and research. BREEAM has served as the basis for many of the green building certification systems, including LEED and Green Globes. BREEAM is used in 93 countries around the world, with more than 2,326,200 projects registered and 565,000+ certificates issued. BREEAM aims to deliver sustainable solutions, encourage a holistic approach to sustainability that is based on sound science and measures what is important, and improve building environmental performance. Performance is measured in 9 categories: Management, Health & Well-being, Energy, Transport, Water, Materials, Waste, Land Use & Ecology, and Pollution. Innovation is rewarded through exemplary credits within specific issues. Each category is weighted to encourage projects to focus on the categories with the highest environmental impact and minimum standards are set to ensure that key aspects of performance across the standard are met to achieve the higher levels of certification. This provides a level of flexibility for use while maintaining the rigor of the standard.

    The standards are set by building life-cycle stage and define the building types that are included. Where a building type is not included, BREEAM offers a Bespoke service that tailors the criteria in the existing standards to the development's specific use, sustainability opportunities and its location without compromising the rigor of the standard. The BREEAM standards are regularly reviewed and updated to reflect the latest building science research and knowledge.

    BREEAM provides online tools to facilitate the benchmarking and certification process. Project teams select an Assessor, trained and licensed by BRE, to verify the performance described is accurate and supported by evidence required by the standard. The Assessor submits an assessment report to BRE, detailing how they confirmed compliance with the BREEAM criteria and provides the supporting evidence. The report is subject to a quality assurance process and once passed, the certificate is issued. For all BREEAM rating systems other than In-Use, there are five ratings: Pass (1 Star), Good (2 Stars), Very Good (3 Stars), Excellent (4 Stars) and Outstanding (5 Stars). BREEAM In-Use has six ratings, with Acceptable (1 Star) as the lowest rating and Pass (2 Stars) through Outstanding (6 Stars) above. For New Construction and Refurbishment and Fit Out, an interim certificate can be issued at the Design Stage and the final certificate issued once construction is complete. On-site visits are required for certification.

    leed logo

    Leadership in Energy and Environmental Design (LEED)—was created by the U.S. Green Building Council (USGBC), for rating design and construction practices that continue to define green buildings in the United States and around the world. LEED is used throughout North America as well as in more than 150 countries with over 110,000 projects currently registered and certified across the globe. Hundreds of state governments, cities, towns, and counties have enacted sustainable legislation, ordinances, or policies, many of which specifically call for LEED certification.

    LEED consists of credits which earn points in several categories including: Integrative Process, Location and Transportation, Sustainable Sites, Water Efficiency, Energy and Atmosphere, Materials and Resources, Indoor Environmental Quality, Innovation, and Regional Priority. One hundred and ten points are available across these categories with mandatory prerequisites such as minimum energy and water-use reduction, recycling collection, and tobacco smoke control. Within each category are credits that pertain to specific strategies for sustainability, such as the use of low-emitting products, reduced water consumption, energy efficiency, access to public transportation, recycled content, renewable energy, and daylighting. Since its inception, LEED standards have become more stringent as the market has changed and expanded to include distinct rating systems that address different building types: New Construction, Existing Buildings, Commercial Interiors, Core & Shell, Schools, Retail, Healthcare, Homes, Cities and Communities, and more.

    The LEED certification process takes place at LEED Online. Project teams are required to compile documentation to show compliance with LEED requirements and upload this documentation to the LEED Online website. The documentation is then reviewed by the Green Building Certification Institute (GBCI); a LEED certification is earned if all prerequisites and a sufficient number of credits are earned. There are four levels of LEED certification: Certified, Silver, Gold, and Platinum. There are no on-site visits required and certification can occur upon completion of construction. However, buildings can be recertified in order to measure performance. LEED v4.1 also places a greater emphasis in the credits on operational and embodied carbon.

    green globes logo

    Green Globes—originated in Canada and was then brought to the U.S. by the Green Building Initiative (GBI). It is now cited in many Federal, State, and Municipal mandates.

    Buildings are rated on a 1,000 point scale spread across seven categories: Energy, Indoor Environment, Site, Water Efficiency, Materials, and Project Management. Users can indicate that certain credits may not be applicable to a project, a feature unique to Green Globes. It also does not have prerequisites. A Green Globes rating requires a Green Globes Assessor to perform an onsite assessment of the building. This ensures that the self-reported claims made in the online documentation are verified. Both new construction and existing buildings and interiors can be evaluated using Green Globes; commercial or multifamily.

    The first step toward a Green Globes certification is completing a self-reported online assessment survey, which is required at various stages throughout design and construction. At the construction documents phase and after substantial completion, a Green Globes Assessor will perform a site visit to verify the claims made in the survey. A Green Globes certification of one to four globes can then be earned once verification is confirmed.

    living building challenge logo

    Living Building Challenge (LBC)—is a performance-based system initially launched by the Cascadia Green Building Council. The International Living Future Institute (ILFI) is the umbrella organization for both the Cascadia Green Building Council and the Living Building Challenge.

    The LBC makes stringent demands such as 100% zero energy, 100% net zero water, on-site renewable energy, and 100% recycling or diversion of construction waste. It examines site, water, energy, materials, health, equity, and beauty. All of its tenets are mandatory making it the most rigorous green building certification system in the market today. An on-site audit must occur by a member of the International Living Future Institute (ILFI)

    After online registration, projects must join the living building community where discussions concerning compliance are held, and documentation occurs. Certification occurs twelve months after project completion, with an on-site audit to ensure compliance.

    ZE—The ILFI also provides a certification option for a Zero Energy Building (ZE) under its umbrella of the Living Building Challenge certification. These buildings have 100% of their energy needs supplied by on-site renewable energy on a net annual basis. The ZE Certification verifies that a building is truly operating as claimed, harnessing energy from the sun, wind, or earth to exceed net annual demand. To earn this certification, a building must meet five requirements of the LBC:

    • Limits of Growth
    • Zero Energy
    • Rights to Nature
    • Beauty and Spirit
    • Inspiration and Education.

    According to ILFI, nearly any building can become ZE-certified: new or operational, anywhere in the world.

    Additionally, the ILFI offers the Living Community Challenge, Core Certification, and Zero Carbon Certification.

    passive house institute us logo

    Passive House Institute US (PHIUS)—administers a climate-specific passive building standard and certification system that was developed under a DOE/Building America grant specifically to address complex US climates. Buildings designed and built to the PHIUS+ 2015 Passive Building Standard consume 86% less energy for heating and 46% less energy for cooling (depending on climate zone and building type) when compared to a code-compliant building. The Phius climate-specific passive building standards guide designers and builders in the design and construction of passive building worldwide. They provide a quality-and-conservation-first framework for net zero building. They are internationally applicable and grounded in building science, best practices, and the quality assurance necessary to deliver optimal results. There are certified projects in South Korea, Japan, China, and Israel. In North America, PHIUS is the leading educational institute with most certified passive building professionals trained in North America. PHIUS is also the leading certifier of passive houses and buildings with 95% of all passive construction currently underway. The German Institute is also active in the US and has certified under their program to date about 5% of all passive building construction.

    sustainable sites initiative logo

    SITES—Administered by Green Business Certification Inc. (GBCI), the Sustainable Sites Initiative (SITES) offers a comprehensive rating system designed to distinguish sustainable landscapes, measure their performance and elevate their value. SITES certification is for development projects located on sites with or without buildings—ranging from national parks to corporate campuses, streetscapes to homes, and more. SITES is used by landscape architects, designers, engineers, architects, developers, policy-makers and others to align land development and management with innovative sustainable design. Land is a crucial component of the built environment and can be planned, designed, developed and maintained to protect and enhance the benefits we derive from healthy functioning landscapes. SITES helps create ecologically resilient communities and benefits the environment, property owners, and local and regional communities and economies. Resources are available to help designers understand how SITES interfaces with LEED. For example, if a project earns SITES Gold, it automatically earns credits in the LEED Sustainable Sites category.

    well logo

    WELL—is a performance-based system for measuring, certifying, and monitoring features of the built environment that impact human health and well-being by looking at ten factors, or concepts. They include: Air, Water, Nourishment, Light, Movement, Thermal Comfort, Sound, Materials, Mind, Community, and Innovation.

    WELL is grounded in a body of medical research that explores the connection between the buildings where people spend more than 90 percent of their time, and the health and wellness impacts on occupants. WELL Certified spaces and WELL Core and Shell Compliant developments can help create a built environment that improves the nutrition, fitness, mood, sleep patterns and performance of its occupants. WELL is composed of over 100 Features that are applied to each building project, and each WELL feature is designed to address issues that impact the health, comfort, or knowledge of occupants. Many WELL Features intended to improve health are supported by existing government standards or other standards-setting organizations. WELL Features are categorized as either Preconditions—necessary for baseline WELL Certification or Compliance, or Optimizations—optional enhancements, which together determine the level of certification above baseline certification. The Features of WELL can be applied across many real estate sectors, and WELL v2 is optimized for commercial and institutional office buildings. WELL is further organized into Project Typologies which take into account the specific set of considerations that are unique to a particular building type or phase of construction. For WELL v2, project typologies include: New and Existing Buildings, New and Existing Interiors, Core and Shell, and pilot programs in Retail, Education Facilities, Restaurant, Commercial Kitchen, and Multifamily Residential.

    fitwel logo

    Fitwel is the world's leading certification system committed to building health for all. Fitwel is implementing a vision for a healthier future where all buildings and communities are enhanced to strengthen health and well-being. Fitwel was originally created by the U.S. Centers for Disease Control (CDC) and Prevention and the U.S. General Services Administration. The CDC remains the research and evaluation partner for Fitwel. The Center for Active Design is the licensed operator of Fitwel.

    Certification is available for New Construction and Existing projects. The Fitwel Standard provides tailored scorecards to optimize a project. Scorecards include more than 55 evidence-based design and operational strategies that enhance buildings by addressing a broad range of health behaviors and risks. Projects are awarded a Star Rating from one to three stars The New Construction Certification applies to projects currently in the design stage or under construction and consists of two certification types: Design (prior to occupancy) and Built (post occupancy). A single project or entire portfolio can be certified. The Certification is valid for three years. After this time period, recertification can be initiated. Fitwel's seven health impact categories are: Impacts Surrounding Community Health, Reduces Morbidity and Absenteeism, Supports Social Equity for Vulnerable Populations, Instills Feelings of Well-Being, Enhances Access to Healthy Foods, Promotes Occupant Safety, and Increases Physical Activity.

    International Green Building Rating Systems

    There are many international green building design systems that also set up their criteria through a nationalistic focus, keeping local standards and codes in mind. They include:

    BCA Green Mark Scheme—Based in Singapore, Green Mark was launched by the Building and Construction Authority (BCA) to promote environmental awareness in the construction and real estate sectors. The BCA Green Mark Scheme rates buildings according to five key criteria including: energy efficiency, water efficiency, environmental protection, indoor environmental quality, and other green and innovative features that contribute to better building performance. The program outlines a six step scheme that also offers cash incentives to developers, especially focused on addressing improvements to existing construction in areas such as energy use reduction and materials conservation. BCA Green Mark is tailored for the topical climate and is also aligned with the United Nations Sustainable Development Goals.

    BEAM—Based in Hong Kong, BEAM is a comprehensive standard and supporting process covering all building types, including existing and newly constructed mixed use complexes. BEAM is an initiative that assesses, improves, certifies, and labels the environmental performance of buildings. It is a voluntary program developed in partnership with, and adopted by the industry. BEAM is intended to: stimulate demand for more sustainable buildings in Hong Kong and other regions, giving recognition for improved performance and minimizing false claims; provide a common set of performance standards that can be pursued by developers, designers, architects, engineers, contractors and operators; reduce the environmental impacts of buildings throughout the planning, design, construction, management and demolition life cycle; and increase awareness in the building community, and ensure that environmental considerations are integrated at the beginning of a project.

    BEAM assessments are currently undertaken by the Business Environment Council (BEC), an independent, nonprofit, environmental information center, under the guidance of the BEAM Society Executive Committee. Certification can only be issued upon building completion due to a significant number of credits being based on actions taken during construction and upon completion.

    CASBEE—in Japan is composed of four assessment tools corresponding to the building life cycle. "CASBEE Family" is the collective name for these four tools and the expanded tools for specific purposes. The CASBEE assessment tools are CASBEE for Pre-design, CASBEE for New Construction, CASBEE for Existing Building and CASBEE for Renovation, to serve at each stage of the design process. Each tool is intended for a separate purpose and target user, and is designed to accommodate a wide range of uses (offices, schools, apartments, etc.) in the evaluated buildings.

    CASBEE covers the assessment fields of energy efficiency, resource efficiency, local environment, and indoor environment. Both indoor and outdoor spaces are considered as part of the assessment but are assessed separately.

    EDGE (Excellence in Design for Greater Efficiencies)—is a green building certification system for new residential and commercial buildings in emerging markets. The program, which engages financiers, developers, regulators, and homeowners, shows property developers how fast and affordable it is to construct resource-efficient and Zero Carbon buildings, enabling them to pass value directly to building owners and tenants. EDGE enables design teams and project owners to assess the most cost-effective ways to incorporate energy and water-saving options into their buildings. An innovation of the International Finance Corporation (IFC), a member of the World Bank Group that focuses on private sector development, EDGE consists of a web-based software application, a universal standard, and a certification system.

    Global Sustainability Assessment System (GSAS)—the first integrated and performance-based green building rating system in the Middle East and North Africa (MENA) region, designed for assessing and rating buildings and infrastructure for their sustainability impacts. The unique green building framework was developed by the Gulf Organisation for Research & Development (GORD) in collaboration with TC Chan Centre at the University of Pennsylvania, and the School of Architecture at Georgia Institute of Technology, and other reputed houses of expertise. GSAS Trust is the certification body responsible for administrating and issuance of GSAS certificates. For more than a decade, GSAS Trust has been helping public and private organizations in their pursuit towards green transformation through its comprehensive suite of services. The GSAS framework provides quantitative measures to assess the environmental footprint for a project over its entire life cycle including the design, construction, and operations phases covering more than 50 key performance indicators. In addition, each certified project must pass the threshold of achieving at least 30% in energy saving, carbon reduction and water saving. GSAS has more than 1,500 registered projects with an equivalent registered assessed area of more than 2 billion sq. ft. in Qatar and the GCC region. Projects on a macro level include districts, neighborhoods, and infrastructure projects, where on a micro level a wide range of building typologies are assessed such as commercial, residential, sports, healthcare, schools, educational, hospitality, and industrial buildings.

    Green Star SA—was developed by The Green Building Council of South Africa, and is based on the Australian Green Building Council tools to provide the property industry with an objective measurement for green buildings and to recognize and reward environmental leadership in the property industry. Each rating tool reflects a different market sector (office, retail, multi-unit residential, etc.). The objectives of the Green Star SA rating tools are to: establish a common language and standard of measurement for green buildings, promote integrated, whole building design, raise awareness of green building benefits, recognize environmental leadership, and reduce the environmental impact of development.

    Green Star SA Certification is a formal process which involves a project using a Green Star SA rating tool to guide the design or construction process during which a documentation-based submission must be submitted as proof of the achievement. A "Design" certification can be submitted for and awarded at the end of the design phase of the project. At the end of construction, a project can submit for and be awarded "As Built" certification, certifying that all green building strategies were in fact incorporated into the final building. The Certified Rating can be achieved prior to practical completion, but must be achieved no later than 24 months after practical completion. As Built submissions must be submitted after practical completion, and the Certified Rating must be achieved no later than 24 months after practical completion.

    Pearl Rating System for Estidama—Estidama, which means 'sustainability' in Arabic, is intended to be the initiative which will transform Abu Dhabi into a model of sustainable urbanization. Its aim is to create more sustainable communities, cities, and global enterprises and to balance the four pillars of Estidama: environmental, economic, cultural, and social. The Pearl Rating System for Estidama aims to address the sustainability of a given development throughout its life cycle from design through construction to operation. Accordingly, three rating stages have been established: Design, Construction, and Operational.

    Within each section there are both mandatory and optional credits and credit points are awarded for each optional credit achieved. To achieve a 1 Pearl rating, all the mandatory credit requirements must be met. To achieve a higher Pearl rating, all the mandatory credit requirements must be met along with a minimum number of credit points.

    Emerging Issues

    New green technologies and materials are always being developed and entering into the marketplace to complement current practices in creating greener environments. Many of these technologies and materials have not been tested long enough in the built environment in order to fully verify their performance. Seek extensive testing and performance data before incorporating new technologies and materials into a project. Also, test beyond the product's green performance for safety, durability, and fire resistance standards from UL and ETL.

    New and more stringent requirements continue to be introduced to the standards and certifications process. Because of the toxicity of many pesticides and fire retardants, and additional means of exposure, testing and certifying beyond product emissions to product content is a trend that will continue to increase.

    There continues to be a shift toward the scientific evaluation of actual performance through Life Cycle Assessments (LCA). While LCAs are not yet a consistent requirement of green building rating systems and codes, there is a trend toward requiring LCAs and improving the methods for conducting them. Greater emphasis is also being placed on achieving resilience in buildings, which is now being addressed in the green building rating systems.

    Achieving a sustainable, lasting outcome can be achieved in a variety of ways for any given project. The rating systems offer options that can help a designer and client tailor the project outcome based on a wide range of goals and approaches to addressing the sustainability issues and other green building requirements.

    life cycle assessment

    Relevant Codes and Standards

    Federal Mandates, Acts, and Executive Orders

    International Code Council

    • International Green Construction Code (IgCC). The IgCC is intended to be used as a jurisdictional and municipal building code for new construction and major renovations. The IgCC is a comprehensive code document; it sets standards for energy conservation, water efficiency, and commissioning, and also includes enforcement procedures and guidelines for existing building renovations.
    • ICC 700 National Green Building Standard. The standard defines green building for single-family and multi-family homes, residential remodeling, and site development projects while allowing enough flexibility to incorporate regionally appropriate best green practices.

    ASHRAE Standards

    Water-related Legislation and Codes

    Material-related Legislation

    Municipal Standards

    Many cities, states, and U.S. Territories have also implemented green standards for public buildings. Every city's, state's, and U.S. Territory's energy goals and requirements are listed, highlighting LEED, Green Globes, and carbon emission reduction goals. New York City and California are two examples of governments that have implemented green standards for public buildings.


    California has implemented green building standards for all major renovations and new construction of public buildings. Executive Order S-3-05 calls to reduce greenhouse gas emissions 80% below 1990 levels by 2050. To accomplish this goal, Executive Order S-20-04 requires all state buildings to reduce energy usage by 20% and achieve a minimum of a Silver LEED rating.

    New York City

    New York City's Local Law 86 requires LEED certification for public buildings with construction costs exceeding $2 million. The NYC Greener, Greater Buildings Plan  is another example of NYC's commitment to sustainability. It requires a combination of benchmarking, energy audits, retro-commissioning, lighting upgrades and sub-metering for the city's largest buildings.

    Additional Resources