The COVID-19 pandemic increased focus on the role of indoor air quality in health outcomes and spurred renewed efforts by building science practitioners and building owners and operators to measure and understand indoor air quality (IAQ) in occupied buildings. Homeowner’s Rehab, Inc., a multifamily affordable housing developer and owner, and New Ecology, Inc. have explored strategies to measure indoor air quality in multiple developments to date. At the same time, new developments such as Finch Cambridge follow green building certification programs such as PHIUS, Enterprise Green Communities, and Fitwel, all of which have requirements related to ventilation and lower-health impact materials. We will review the IAQ monitoring program in place at Finch Cambridge, the first certified multifamily affordable passive house project in Massachusetts, and the attempted monitoring program at the existing development, [HRI to insert Worcester project name]. We will include the first public presentation of 18 months of IAQ data for the Finch Cambridge passive house project, monitored for all units and most common spaces within the building. And, we will provide a review of how the green building certifications obtained at Finch helped guide the team to create a building which is healthier for its residents, in design, construction, and ongoing operations.