LEED v5: The Next Big Shift in IAQ Management

USGBC's new rating requires proactive operational testing and monitoring to ensure buildings remain habitable as they age and are exposed to new risks.
Sept. 20, 2025
6 min read

By SEEMA BHANGAR and LARISSA OAKS, U.S. Green Building Council

The LEED rating system has incentivized exemplary action on indoor air quality (IAQ) since its inception in 1998. The program drove market transformation by normalizing practices such as the adoption of ventilation rates beyond minimum code, more consistent commissioning of HVAC systems, increased investment in high-efficiency filtration, and proactive building operations that reduce occupant exposure to pollutants, as well as by spurring manufacturers to reengineer their product lines toward low-emitting materials and safer ingredients.

Now, an expanded set of air quality features in the newest version of the rating system, LEED v5, is poised to accelerate the next big shift in indoor air quality management: proactive operational testing and monitoring to ensure buildings remain habitable as they age and are exposed to new risks.

The next big shift

As tools and technologies to measure and verify clean air have become cheaper and easier to use, and evidence of the ubiquitous gap between design expectations and operational performance has grown, policymakers, building professionals and researchers are considering: Has the time come to “build the missing meter” to ensure clean air delivery across the operational life of a building—a meter that is about people and workflows as much as it is about tools, technology and data?

Incentivizing indoor air monitoring with LEED v5

While LEED has always elevated the importance of indoor air quality, LEED v5 ties it directly to occupants’ quality of life. All LEED v5 credits and prerequisites are linked to at least one of three main impact areas: quality of life, decarbonization, and ecological conservation and restoration. As the newest version of the rating system, LEED v5 embraces novel approaches and ensures project teams have access to best-in-class resources for health and well-being.

As part of this commitment, LEED v5 encourages integrating this “missing meter” into project plans and designs, offering points for new construction projects that select and install sensors for the most-measured indicators of ventilation effectiveness and overall air quality: particulate matter (PM), carbon dioxide (CO2) and total volatile organic compounds (TVOCs). These sensors complement a prerequisite requirement for monitoring of outdoor airflow.

LEED v5 also encourages sensor use during operations, offering points for existing buildings projects that proactively test and monitor air quality in their buildings. Monitoring requirements are designed to first encourage data collection and understanding, with over half of the available points for data collection and analysis alone, with secondary focus on performance targets. Performance targets for TVOCs were excluded, given the challenges with measuring this parameter with continuous monitoring devices.These sensor measurements complement a prerequisite requirement to complete a basic level of IAQ performance verification.

In addition, LEED v5 encourages teams to design and operate for multiple “performance states” using the latest air quality standards and guidelines that address resilience and performance-based design (ASHRAE 62.1 IAQ procedure, ASHRAE 241, ASHRAE Guideline 44), acknowledging there may be different indoor air quality performance expectations during major episodic, disruptive events.

Bridging the market maturity gap with R&D partnerships

There is a widespread consensus that, in the future, IAQ will be routinely monitored and benchmarked in commercial buildings, along with energy and resource use. LEED and other green building programs point unequivocally in this direction. That said, feedback from early adopters and expert communities indicates that the industry is still in the early stages of scaling, due to a few challenges.

To identify and address these barriers to widespread implementation, USGBC initiated a research partnership with leading academics from EPFLUniversity of California, Berkeley, and the University of Sydney. Spanning interviews with 34 expert contributors across targeted sectors, the findings—presented in a newly released report—showed the industry is at a chicken-and-egg impasse. Progress on protocols, workforce and tools depends on more buildings embracing innovation, but organizations hesitate to adopt new strategies due to uncertainty and lack of established support—making early adoption feel risky and costly.

As the world’s most widely used green building rating system, with over 124,000 certified projects totaling over 13 billion square feet of space, LEED provides a powerful mechanism to inspire, incentivize and support the creation of that critical mass. However, simply expanding implementation is not enough.

We envision a future where every building and professional using air sensors contributes data to make monitoring easier, more cost-effective and more beneficial for owners, operators and occupants. Achieving this will require a coordinated, cross-sector effort to develop policies, standards and implementation-focused research that draws on real-world experience.

Training and capacity-building for better IAQ in schools

USGBC’s Center for Green Schools provides professional development to a growing network of over 700 school district staff from nearly 250 school districts who collectively serve over 9 million students. The Center’s training and capacity-building for K–12 staff includes developing practical tools like its series of IAQ fact sheets, an IAQ Management Planning Toolkit, the Clean Air in Schools course and a regional coaching program for K–12 staff.

To advance the school IAQ research field, the Center convened school leaders and researchers to set a new school IAQ research agenda. The Center also curates a research database of nearly 600 peer-reviewed studies on the built environment and occupant health of schools, paired with supporting research highlights to help school operators translate this research into action.

Learning from our own sensor network

USGBC's headquarters in Washington, D.C., has triple Platinum-level certifications in LEED, WELL and TRUE in a larger building that is also LEED Gold. The USGBC space is also used as a living laboratory for strategies promoted in the LEED rating system, including continuous monitoring IAQ sensors. Each monitor has a QR code so that staff and visitors may see how the space is performing in real time, with a central dashboard to evaluate trends. The facilities team uses this knowledge to inform the health and well-being strategy of the office.

Each building team taking steps toward consistent, continuous IAQ monitoring contributes to a healthier future for building occupants, from offices to schools or multifamily residences. Join USGBC and our communities of expertise and practice, as we leverage the LEED v5 rating system in conjunction with innovative research partnerships to advance the movement for cleaner indoor air.

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About the Authors

Based in Oakland CA, Seema Banghar is USGBC's principal for Healthy Buildings and Communities. LEED Specialist Larissa Oaks is based in Burlington VT.

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