The WELL Performance Rating and Indoor Air Quality: What You Need to Know

If you’re familiar with WELL, then you know that WELL v2 is the flagship certification for companies aiming to optimize their buildings for health and well-being. However, due to the breadth of optimizations required to achieve certification, WELL also provides several ratings that act as stepping stones to achieving the full WELL v2 certification.

These ratings, including the WELL Performance Rating, WELL Health-Safety Rating, and WELL Equity Rating, contain a smaller subset of requirements from the WELL v2 certification and are focused on specific outcomes and/or procedures.

In this article, we’ll be talking about the WELL Performance Rating, specifically what the rating includes, how it’s different from WELL v2, and the role of indoor air quality (IAQ) in achieving the rating.

What is the WELL Performance Rating?

The WELL Performance Rating is a collection of features from the WELL v2 certification that focuses only on measuring building performance, specifically how well it maintains a healthy indoor environment.

Compared to the other ratings and the WELL v2 certification, the WELL Performance Rating is the most data-driven, only accepting performance-based verification pathways (sensor data from continuous monitors, on-site performance testing, and occupant experience surveys). 

The WELL Performance rating was developed by the International WELL Building Institute (IWBI) in partnership with several companies, including Kaiterra, Carrier, Honeywell, Johnson Controls, Schneider Electric, and Trane Technologies. The WELL Performance Rating was designed to be both a stand-alone designation as well as a milestone toward WELL v2 certification. 

For projects planning to pursue WELL v2 down the road, starting with the WELL Performance Rating will make the certification journey faster, easier, and more cost-effective by providing a head start on meeting the certification’s requirements.

In either case, achieving the WELL Performance Rating means that buildings will incrementally improve their indoor environmental quality each year, and they can share this data with occupants to demonstrate their ongoing commitment to health and well-being.

Core Components of the WELL Performance Rating

Instead of concepts and features that are found in the WELL v2 certification, the WELL Performance Rating is organized into seven themes, with 33 features total within those themes:

• Indoor Air Quality (9 features)
• Water Quality Management (4 features)
• Lighting Measurements (2 features)
• Thermal Conditions (2 features)
• Acoustic Performance (5 features)
• Environmental Monitoring (6 features)
• Occupant Experience (5 features)

The Environmental Monitoring and Occupant Experience themes are unique to the WELL Performance Rating due to their emphasis on building performance data:

• The Environmental Monitoring theme is more about the act of measurement than demonstrating compliance with thresholds. The intent of these features is to encourage projects to regularly monitor the indoor environment and make data-driven decisions for occupant health.
• The Occupant Experience theme is designed to help projects understand how their indoor environment is directly affecting occupants. The required surveys in this theme align with the occupant surveys prescribed in WELL v2’s Thermal Comfort and Community concepts.

Unlike the WELL v2 certification, which offers multiple tiers of achievement (Silver, Gold, and Platinum certification), WELL ratings are an all-or-nothing achievement, simply requiring projects to earn a designated number of points to receive the rating. 

For the WELL Performance Rating, projects must earn 21 points. Because there are no required preconditions or optimizations in the rating, projects have more flexibility in determining how they will achieve those 21 points.

Accepted Verification Pathways in the WELL Performance Rating

The WELL Performance Rating only accepts three verification pathways due to its sole focus on building performance data. These pathways are:

1. On-site, short-term testing conducted by a WELL Performance Testing Agent or other qualified professional
2. Sensor data collected from permanently installed continuous monitors
3. Occupant experience surveys, focus groups, and/or observations

For some features, a technical document, ongoing data report, or letter of assurance is an acceptable verification method, as these documents serve as proof that one of the performance-based pathways has been implemented.

How is the WELL Performance Rating Different From WELL v2?

Compared to the broader WELL v2 certification, the WELL Performance Rating has many differences in terms of scope, requirements, and level of investment:

Indoor Air Quality Requirements in the WELL Performance Rating

IAQ remains front and center in the WELL Performance Rating due to its major impact on occupant health, well-being, and comfort. By investing in continuous IAQ monitoring, projects can potentially score points on 14 out of the 33 total features via the sensor data pathway, depending on the exact capabilities of the continuous monitor you choose:

It’s important to note that the total number of points you can achieve depends on the IAQ monitor that you choose, because different monitors measure different parameters.

For example, choosing a solution like Kaiterra’s that also measures temperature and relative humidity can automatically increase your point potential by meeting requirements in the Thermal Conditions theme - keep reading to see the detailed breakdown of how Kaiterra monitors contribute up to 13 points in the WELL Performance Rating.

Focus on the Continuous Monitoring Pathway

With the WELL Performance Rating’s strong emphasis on data collection, the continuous monitoring pathway is the ideal verification pathway for applicable features because it allows for 24/7/365 data collection and analysis.

Compared to one-time testing, the continuous monitoring pathway provides a comprehensive picture of building performance and provides the large volume of data required to surface issues and identify the correct solutions.

The WELL Performance Rating offers continuous monitoring as an acceptable verification pathway for the following parameters:

Additional details can be found in the Performance Verification Guidebook, a technical manual that covers all aspects of performance-based features, including how and where to place sensors and sampling points, the required density and technical specifications for analytical techniques, and the range and calibration periods for direct read devices and sensors. The Guidebook also includes a section on continuous monitoring, which provides detailed information on how to use and maintain continuous monitors.

WELL Performance Rating projects using continuous monitors must submit their data using the Sensor Data Compliance Calculator, a tool that provides guidance for using continuous monitors as well as a standardized format to determine compliance with each feature in the rating.

Placement, Density, and Calibration Requirements for IAQ Monitors

Based on the Performance Verification Guidebook, WELL Performance Rating projects using continuous monitors for IAQ and thermal comfort must meet the following requirements for:

• Placement: Monitors can be installed on the wall, at a height of 1.1-1.7 m [3.6-5.6 ft] above the finished floor, as well as on the ceiling (only if the ceiling is no higher than 3.7 m [12 ft] above the floor, if no displacement ventilation is used, and if there is evidence that air is evenly mixed at ceiling height). Monitors must be at least 1 m [3.3 ft] away from interior doors, windows, fans, HVAC vents, or any other potential influences on air quality or thermal comfort readings.

• Location: Monitors should be distributed across all faces of the building, throughout all HVAC zones, in all regularly occupied spaces, and across different floors (including the lowest and highest regularly occupied floors).

• Density: For all parameters except radon:
   
  • Projects with occupiable space of < 3250 m²: 1 monitor per 325 m² [3,500 ft² ] in occupiable spaces (minimum 2) 
  • Projects with occupiable space of 3250-25,000 m²: 1 monitor per 500 m² [5,400 ft² ] in occupiable spaces (minimum 10) 
  • Projects with occupiable space of > 25,000 m²: 1 monitor per 1000 m² [10,800 ft² ] in occupiable spaces (minimum 50)

• Calibration: Per the 2025 Q3 Performance Verification Guidebook, all continuous monitors must be calibrated every three years with one of two types of accepted calibration procedures (note: software calibration remains invalid):
   
  • Manufacturer calibration, where the devices are returned to the manufacturer for calibration.
  • Field reference calibration, where the devices are field calibrated using a reference sensor, which must be done across at least two different concentrations for each contaminant to capture performance over a sufficient range.

How Kaiterra's Indoor Air Quality Monitoring Helps Achieve Certification

Kaiterra provides both wired and wireless continuous IAQ monitoring solutions that are purpose-built for WELL, whether you’re pursuing the WELL Performance Rating, WELL v2 certification, or both. All Kaiterra solutions, including the Kaiterra Data Platform, have the Works with WELL trademark, indicating our alignment with specific features in the WELL standard. 

By meeting WELL’s technical specification requirements for continuous monitors and measuring a comprehensive suite of air quality and thermal comfort parameters, Kaiterra’s solutions can help your project earn a significant portion of the points you need to achieve the WELL Performance Rating. 

Achieve Up to 13 Points in the WELL Performance Rating With Kaiterra

Kaiterra’s air quality monitors measure all of the parameters required to achieve 13 IAQ-related points in the WELL Performance Rating, including PM2.5, PM10, TVOC, CO2, Ozone, CO, NO2, temperature, and relative humidity. This means that projects only need to earn 8 more points to achieve the WELL Performance Rating! 

Achieve Up to 14 Points in WELL Core for the WELL Performance Rating

Landlords or building owners pursuing the WELL Performance Rating for their core and shell projects (otherwise known as the base building) must follow the WELL Core version of the Performance Rating requirements.

Like the WELL Core version of WELL v2 certification, the features of the standard or rating are the same, but the total number of possible points depends on the amount of leased space a landlord/owner can access.

Different features call for different scales of deployment, whether it’s non-leased space only or throughout the whole building. These varying degrees of implementation result in varying numbers of possible points. Projects that can only access non-leased space will achieve fewer points than those with full building coverage due to a smaller project area.

If you are monitoring air quality in only non-leased spaces, you can earn points in 9 features, meaning projects only need 12 more points to satisfy the Performance Rating requirements.

Compared to monitoring in only non-leased spaces for WELL Core, as well as the standard WELL Performance Rating, projects pursuing full building coverage for WELL Core can achieve the highest number of features from continuous IAQ monitors.

By installing sensors throughout the whole building, these projects can achieve up to 14 features. While the standard WELL Performance Rating offers 13 features from continuous monitors, WELL Core projects going for full building coverage can achieve not only these 13 features but also one innovation feature by installing monitors in leased spaces (or if non-leased space takes up at least 40% of the project area). This one solution secures two-thirds of the features needed to achieve the WELL Performance Rating!

Why You Should Partner With Kaiterra for the WELL Performance Rating

In addition to helping projects achieve over half of the points needed to earn the WELL Performance Rating, Kaiterra’s solutions have built-in optimizations that make it simple and efficient to meet your WELL goals.

Submission made easy with the WELL Compliance Report

While the Sensor Data Template helps standardize data submission for WELL, there is still a significant amount of work required to organize the data, compare against WELL’s thresholds, and fill out the template prior to submission.

Also, for many projects using sensor data, this is one of just a handful of times when they determine whether or not they are meeting WELL’s requirements. If a project finds out at this stage that their building is not fully compliant with WELL’s air quality thresholds, then their certification will likely be delayed as they diagnose and fix the problem.

In order to further simplify sensor data submission and prevent unexpected compliance issues, Kaiterra provides every customer with the WELL Compliance Report. This tool lives on the Kaiterra Data Platform and continuously benchmarks IAQ data from sensors against WELL’s requirements, identifying any risks and helping projects gauge their certification progress.

When it comes time to submit the data, the WELL Compliance Report automatically organizes the data into the IWBI’s preferred format and directly submits the formatted data to the IWBI team.

The WELL Compliance Report works with both the WELL v2 Certification and the WELL Performance Rating, helping projects substantially reduce the amount of time and labor required to submit their data and prove compliance, while also minimizing the risk of errors and helping projects ensure that they achieve certification on time.

Modular sensor design simplifies the calibration process

All Kaiterra monitors are built with a modular sensor that can be easily swapped out with a new sensor within minutes. This process meets WELL’s requirements for manufacturer calibration, as each new sensor comes with a calibration certificate that projects can submit as proof of calibration to the IWBI.

Compared to pulling all monitors off the wall and shipping them to the manufacturer (standard manufacturer calibration) or having a trained professional come on-site to manually calibrate each sensor with specialized equipment (field-reference calibration), Kaiterra’s modular sensors offer a far more efficient, cost-effective, and hassle-free method of performing sensor calibrations.

Replace performance testing and achieve up to 9 points in WELL v2 at the same time

If your goal is to achieve WELL v2 certification in the future, then installing Kaiterra’s air quality monitors for the WELL Performance Rating will help you remove the need for performance testing for Air and Thermal Comfort concepts, and automatically give you 9 points toward your WELL v2 certification with no extra work.

If you’re unfamiliar with the WELL v2 scoring system, that’s almost enough points to take your project to the next tier of certification, with just one solution! Read more about how Kaiterra’s monitoring solutions can help you earn more points in the WELL v2 air and thermal comfort concepts.

Because continuous monitoring is now a viable option to achieve preconditions in Air and Thermal Comfort, you no longer need to use performance testing for these concepts. This significantly reduces the amount of time, money, and labor required to meet these requirements and earn additional optimization points.

By going the sensor data route, WELL projects can avoid the challenges, complexities, and costs associated with performance testing, while also gaining a much deeper understanding of how their buildings perform with continuous, real-time data. If you want to know more about how sensor data and performance testing compare, read this article for an in-depth comparison and learn how to choose the right solution for your project.

By partnering with Kaiterra, WELL projects can not only leverage continuous, real-time IAQ data to secure over half of the necessary features for the WELL Performance Rating, but also lay a solid foundation for future WELL v2 certification while continually optimizing their built environment for occupant health and well-being along the way.

Ready to Optimize Your WELL Performance Rating Project?

Reach out today to connect with a WELL Accredited Professional (AP) on the Kaiterra team, and to learn more about how our enterprise air quality monitoring solutions can make it faster and easier to achieve your WELL goals.