Green Building Rating Systems

Updated for 2025: This blog was originally published on November 30, 2022 and has been updated on August 22, 2025 to include the most current information on green building rating systems.

Choosing the right green building rating system is an important step in shaping your project’s sustainability goals. Each system has its own focus, whether it’s energy efficiency, occupant well-being, carbon reduction, or holistic performance.

This article provides a high-level overview of the most commonly used rating systems, highlighting what makes each unique and how they can align with your project objectives. Our goal is to give you the clarity you need to identify which certification path may be the best fit for your next building.

LEED – U.S. Green Building Council

Developed by the USGBC, LEED is a consensus-driven, internationally recognized, third-party verification system (offsite, via documentation). Points are awarded, out of 110, for sustainable improvements in areas such as energy efficiency, water usage, CO₂ emission reductions, indoor environmental quality, and the stewardship of natural resources.

There are prerequisite requirements that must be met before any points can be accrued toward certification. Based on the number of points earned (beginning at 40), projects can achieve levels of Certified, Silver, Gold, or Platinum. Each successive level is more challenging to attain, typically requiring higher costs, but offering greater long-term financial and environmental benefits.

LEED is the world’s most widely adopted green building rating system, with more than 100,000 buildings using it today.

In April 2025, the USGBC released the first major upgrade in over a decade: LEED v5. This new version is a comprehensive overhaul centered on “decarbonization, quality of life, and ecological conservation and restoration.” The primary performance metric has shifted from reducing energy usage to reducing greenhouse gas emissions. Additionally, new assessment prerequisites are tied to these three central pillars of LEED v5.

Structural changes were also introduced. The LEED rating system will now undergo revisions on a three-year cycle, similar to ASHRAE 90.1 and the IECC codes.

Another notable change is the addition of specific Platinum requirements. Regardless of how many points a project earns, Platinum certification cannot be achieved without addressing specific credits related to energy efficiency, carbon emissions, and renewable energy use.

WELL – International Well Building Institute

The WELL Building Standard is based on the premise that healthier buildings improve occupant performance and help organizations outperform their competition. Currently, there are nearly 100,000 locations and more than 6 billion square feet enrolled worldwide.

The rating system is organized into 10 concepts—Air, Water, Nourishment, Light, Movement, Thermal Comfort, Sound, Materials, Mind, and Community—supported by 108 features. These features address building design, culture, operational policies, and maintenance protocols. Each project must meet mandatory preconditions (fundamental to a WELL Certified space), while optimizations allow projects to earn points toward certification.

Depending on the number of points achieved (starting at 40), projects can earn Bronze, Silver, Gold, or Platinum certification. Higher levels typically require greater investment but also yield stronger long-term returns in health, performance, and market value.

Like LEED, WELL relies on an offsite documentation review. However, WELL adds an additional layer of quality control with onsite performance verification through a series of tests, spot-checks, and measurements. This ensures that the building operates as designed and documented.

Over the past several years, the USGBC and IWBI have worked together to create “crosswalks.” These allow projects pursuing both LEED and WELL to harmonize credits and use the same documentation across the two systems, streamlining the certification process.

Green Building Initiative Green Globes – Green Building Initiative (GBI)

A competitor to LEED, GBI adapted Green Globes (a Canadian web tool, based on BREEAM Canada) for U.S. commercial buildings, arrived in 2004, introducing the Green Globes environmental assessment and rating tool to the U.S. market.

In 2005, GBI was the first commercial building organization to become an ANSI Accredited Standards Developer. GBI has since become the global provider of the Green Globes and federal Guiding Principles Compliance certification and assessment programs.

GBI is currently working on its newest standards development process, Green Globes for Existing Buildings.

The system is based on 1,000 available points, with 350 being the minimum for certification.  The levels of certification are one, two, three, and four Green Globes.  As with all other systems, higher levels of certification have cost/benefit characteristics.

The biggest difference between LEED, and Green Globes is in the way the project is documented.  Green Globes uses an online questionnaire to document/input project information.  Then an initial Third Party Assessments is performed.  The final assessment takes place Onsite, where all aspects of the project’s performance are verified.

Lastly, the third party Green Globes Assessor is available throughout the process, to answer questions, and help guide the process.

ENERGY STAR for Commercial Buildings – US Department of Energy/US Environmental Protection Agency

ENERGY STAR, delivered through its Portfolio Manager software, is one of the most widely used energy benchmarking programs in the U.S. and Canada. In fact, ENERGY STAR scores are often referenced by other green building rating systems to establish baseline performance benchmarks.

Portfolio Manager allows building owners to input utility bills and basic building information to generate an ENERGY STAR score. Each building is compared to similar facilities, with performance measured across energy, water, waste, and greenhouse gas emissions. The result is a score on a scale of 1–100, where 50 represents average performance and 100 is best.

According to the ENERGY STAR Portfolio Manager website, nearly 25% of U.S. commercial building space is actively benchmarking in the program. Buildings that achieve a score of 75 or higher may qualify for ENERGY STAR certification, which must be verified by a licensed Professional Engineer or Registered Architect.

Certified buildings use, on average, 35% less energy than comparable buildings, making ENERGY STAR one of the most impactful and cost-effective rating systems. The program currently covers 18 broad categories of property types, with more than 80 variations.

Many municipal programs, such as New York City’s Local Law 97, use ENERGY STAR as a baseline for performance ratings, tying it directly to regulatory compliance.

Living Building Challenge – International Living Future Institute

Unlike the rating systems previously discussed, the Living Building Challenge measures actual performance rather than “modeled or anticipated” performance. For this reason, projects must have at least twelve consecutive months of performance data before a building is audited.

The Living Building Challenge consists of seven performance categories, or “Petals”: Place, Water, Energy, Health + Happiness, Materials, Equity, and Beauty.

Each Petal is subdivided into Imperatives, for a total of twenty Imperatives in the Challenge. The number of Imperatives required depends on the “typology” of the project (New Construction, Existing Building, Interior, etc.).

Living Building Challenge projects are intended to be holistic—addressing aspects of all seven Petals through the Core Imperatives. The Challenge seeks to make projects regenerative, having net-positive rather than negative environmental impacts.

The Living Building Challenge encourages projects to have their own utilities: generating energy, collecting water, and processing waste onsite. However, utilities can also come from outside the project.

IgCC –International Code Council –Advanced Energy Design Guides – ASHRAE

One often overlooked option is to forgo certification and simply build an efficient, sustainable building. A growing number of projects are opting to build to the requirements of LEED or another certification system without pursuing official certification. Building owners can use the money saved on registration and certification fees to improve or highlight sustainable aspects of the building. To do this, there are several options:

IgCC (ASHRAE 189.1)

This is the culmination of years of cooperation between the American Society of Heating, Refrigerating and Air-Conditioning Engineers, the International Code Council, the American Institute of Architects, the Illuminating Engineering Society, and the U.S. Green Building Council.

As with most codes, ASHRAE developed 189.1 as a green building standard in 2009, and ICC developed it into the IgCC the following year. However, since ASHRAE 189.1/IgCC was created in partnership between the two (and several other organizations), they are more closely aligned.

The idea of this partnership is to produce a model green code for jurisdictions to enforce. However, it can also be used as an “above code” guideline for creating even more sustainable buildings. The IgCC is compatible with the IECC, ASHRAE 90.1, and many other standards. Additionally, there are synergies between it and LEED that make earning certain credits easier.

If you are looking to create a sustainable building without the complications and costs associated with a certification rating system, the IgCC is worth considering.

With New York, Boston, and other cities designing greenhouse gas reduction and sustainability programs, it is possible that the IgCC is the energy code of the future. Already, jurisdictions across the country are adopting it as a model code, which also creates more sustainable buildings.

ASHRAE – Advanced Energy Design Guides

Finally, the ASHRAE Advanced Energy Design Guides are probably the simplest way to create an energy-efficient building. The guides are created for specific types of buildings (Office, School, Retail, Hospital, Warehouse, etc.), so they cover the most common, but not all, project types.

There are three types of guides:

1. Creates a building that exceeds an ASHRAE 90.1-1999 baseline by 30%
2. Creates a building that exceeds an ASHRAE 90.1-2004 baseline by 50%
3. Is intended to create a Zero Net Energy building

The 50% Guides are one method for earning points under the LEED Energy and Atmosphere Credit: Optimize Energy Performance (6 points instead of the maximum 18 available through modeling).

The Guides are compatible with most energy codes, but some aspects may need to be upgraded to meet the requirements of the latest codes. The Guides can be purchased from ASHRAE, but if you can work in a digital format, they are available as free downloads.

As with the IgCC, the Guides were created through a collaboration—this one involving the American Institute of Architects, the Illuminating Engineering Society, the U.S. Green Building Council, and the Department of Energy.

Conclusion

Green building rating systems shape more than certifications—they drive efficiency, support occupant health, reduce environmental impact, and enhance long-term asset value. With so many options to consider, identifying the right framework for your project can be challenging.

At Schnackel Engineers, we guide owners and design teams through these systems with clarity, helping you achieve certifications while delivering real-world performance benefits. Contact us today to explore which green building rating system is the best fit for your project and how we can help you succeed.

Updated for 2025: This blog was originally published on [November 30, 2022] and has been updated on [August 22, 2025 to include the most current information on green building rating systems.