Green Building Rating Systems

The following blog is intended to give you a bit of information, about what makes each green building rating system unique, in order to help you make an informed decision about which system will be the best fit for your project.  We will highlight the main points of each rating system, without getting into the minute details, as there are many details.  For a more complete look at all of the details of each rating system, click on the hyperlinks in the headings.

LEED – U.S. Green Building Council

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

There are prerequisite levels of efficiency that must be met prior to the accrual of any points toward certification.  Based on the number of points (beginning at 40), levels of certification, Silver, Gold, and Platinum, are achieved.  Each succeeding level is harder to achieve, with increased costs, but also provides greater long-term financial and environmental benefits.

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

News: At the latest Greenbuild (November 2022), the USGBC adopted measures to upgrade v4, making the Minimum Energy Performance and Optimize Energy Performance requirements more stringent.  This will mean that higher levels of certification will be even more difficult to obtain.

The membership also decided to skip adoption of v4.1, and move directly to the development of LEED v5.

Lastly, they announced the intent to streamline LEED/WELL dual certification, making it easier for projects seeking to achieve both certifications.

WELL – International Well Building Institute

The WELL rating system is based on the premise that healthier buildings increase occupant performance and helps companies outperform their competition.  Currently there are more than 33,000 enrolled buildings throughout the world.

This rating system has ten concepts (air, water, nourishment, light, movement, thermal comfort, sound, materials, mind, and community), with 108 features addressing design, culture, operational policies, and maintenance protocols.  The features consist of mandatory preconditions (considered fundamental to a WELL certified space) and optimizations, which earn points toward certification.

Depending on the number of points achieved (starting at 40), projects earn Bronze, Silver, Gold, and Platinum levels of certification.  Again, the higher levels of certification require additional investment with increased long-term returns.

Like LEED, documentation goes through an offsite series of reviews.  However, the documentation review is backed by an onsite performance verification via a series of performance tests, spot-checks, and measurements.  These verification’s ensure that the building is operating as designed and documented.

Green Globes Assessment Protocol for Commercial Buildings – Green Building Initiative

A competitor to LEED, GBI adapted Green Globes (a Canadian web tool, based on BREEAM Canada) for U.S. commercial buildings.  Having arrived in 2004, it was the first introduction of 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 assessment 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, via its Portfolio Manager software, is one of the most used energy benchmarking programs in the US and Canada.  Additionally, ENERGY STAR scores are referenced by other green rating systems to establish basic performance benchmarks.

The Portfolio Manager software allows building owners to input a building’s utility bills, and some additional basic information, to obtain an ENERGY STAR score.  The building is then compared against similar buildings (measuring energy, water, waste, and greenhouse gas emissions) and given a score of 1-100.  In terms of score, 100 is best, and 50 is average.

According to the ENERGY STAR Portfolio Manager website, “Nearly 25% of U.S. commercial building space is already actively benchmarking in Portfolio Manager”.  Building owners who achieve a score of 75% or better, can receive a certification.  The final score needs to be certified by a licensed professional engineer or registered architect.

Buildings that earn the ENERGY STAR certification use, on average, 35% less energy than comparable buildings.  The system has 18 broad categories of property types with over 80 total variations.

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, also known as, “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 come from outside the project.

IgCC – International Code Council

One, often overlooked, option is to forego the 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.  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:

The IgCC (ASHRAE 189.1)
This is the culmination of years of cooperation between The American Society of Heating, Refrigerating, and Air-Conditioning Engineers, International Code Council, American Institute of Architects, Illuminating Engineering Society, and U.S. Green Building Council.

As with most codes, ASHRAE developed 189.1 as a green building standard in 2009.  Then ICC developed 189.1 into the IgCC the following year.   Since then, ASHRAE and ICC collaboratively created ASHRAE 189.1/IgCC along with several other organizations.

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

With New York, Boston, and other cities designing Greenhouse Gas Reduction/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 Advanced Energy Design Guides are probably the simplest way to create an energy efficient building.  The guides are created for specific, but many common types of buildings such as: office, school, retail, hospital, warehouse, etc.

There are 3 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 for the LEED Energy and Atmosphere Credit – Optimize Energy Performance (6, instead of the maximum 18, available through modeling).

The guides are compatible with most energy codes; however, some aspects may need to be upgraded to meet the requirements of the latest codes.  The guides can be purchased from ASHRAE, and are even available as free digital downloads.

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

Conclusion

We hope this blog has been informative for you and that the descriptions of each green building rating system provided above have helped you choose which ones to research further. If you need assistance with making an informed decision about which rating system will be the best fit for your project, please contact us today.