Flossmoor Hills School Tackles Persistent Humidity Issues with New HVAC Strategies

Concerns over persistent humidity issues in Flossmoor SD 161 schools took center stage at the Board of Education meeting on August 4, 2025. Officials revealed ongoing challenges with air quality and building conditions, particularly at Flossmoor Hills, where humidity levels have reached alarming highs.

During the meeting, it was disclosed that air quality tests are scheduled to ensure the safety of students and staff, despite previous assurances that conditions have always been safe. The district is taking proactive measures, including additional cleaning to address mildew caused by extreme humidity levels.

Mechanical engineer Matt Burton from Wold provided a detailed account of the humidity issues that have plagued the schools since HVAC improvements were made in 2021. He explained that the problem peaks during the late summer months, with humidity levels in some classrooms reaching 90%. Despite various adjustments to the HVAC system, including the installation of new exhaust fans and dehumidification modes, the building continues to struggle with negative pressure, leading to infiltration of untempered air.

Burton emphasized that the root of the problem appears to be related to the building envelope, particularly gaps in insulation and construction flaws dating back to the 1960s. Recent thermal imaging tests have indicated potential air leaks, prompting the district to engage forensic architecture engineers for further investigation.

While Flossmoor Hills remains the primary focus, Western Avenue School has also experienced humidity issues, albeit to a lesser extent. Plans are in place to implement similar HVAC improvements at Western Avenue in the upcoming summer.

The board's commitment to addressing these challenges reflects a broader concern for student and staff well-being as the new school year approaches. As the district continues to monitor conditions and explore solutions, the community remains hopeful for a resolution to these ongoing issues.