Many Boston public schools are said to have bad air. Report calls poor ventilation, leaking roofs red flags.

According to The Boston Globe, a city report says that more than half of Boston’s schools are plagued by poor or deficient air quality, which studies have linked to low student achievement and high rates of asthma.

The findings, released Wednesday, are based on an examination of schools’ ventilation systems or the lack of them, and other factors that can affect air quality, including the inability to open windows.

Boston Mayor Martin Walsh is quoted as saying, “The city’s schools have a ‘history of neglect.’”

This is not an uncommon problem in city-owned buildings, which are often neglected due to lack of taxpayer funds. But this neglect could result in costs that are far more than just repair—like student/teacher illnesses and absenteeism.

Source: Jessica Rinaldi for The Boston Globe


A new technology called Aeroseal can solve problems like this and save school districts both time and money. Aeroseal s a product that seals small leaks in the ductwork. No attic work is required by the crew to work the equipment. It is monitored by a computer program that tells when the pressure of the ductwork is low enough that most of the leakage has been sealed.

Read the case study below to see how Aeroseal rescued the renovation of a school in this one example of many Aeroseal success stories.



During the floor-to-ceiling renovation of the Gallego Intermediate School, contractors removed the existing ceiling tiles to find ductwork that was in such bad shape, replacing the entire duct system seemed to be the only option. The building’s HVAC included 34 individual units, each with its own supply and return ducts, all made of duct board that was literally falling apart at the seams. Some of the ducts were in such disrepair that they made leakage testing impossible.

Unfortunately, the Tucson, Arizona-area school district couldn’t afford either the additional expense or time necessary to replace the existing duct system. Beyond the estimated $200,000 dollars it would have cost for the work, the school was set to open in three months and replacing the ductwork would have taken twice that time.

Faced with this project-halting dilemma, a consulting engineer on the project suggested they look at Aeroseal, a new duct sealing technology he had seen demoed at a recent industry seminar. The Aeroseal experts at GreenSeal were called in to share information about the new technology and in just a matter of days, they began the work.

Given the poor condition of much of the existing ductwork, the GreenSeal crew began reconnecting and repairing the most dilapidated portions using tape and mastic. Even after this work, testing showed a total system leakage rate of about 49,000 CFM. Then the Aerosealing began.

Aeroseal at work

It took GreenSeal less than two weeks to Aeroseal all 34 duct systems – both supply and return. The final results showed total leakage down to 8,000 CFM – an 85% reduction and well below the 5% leakage rate they were targeting. The total cost for Aerosealing was a fraction of the estimate for duct replacement and best of all, the school opened on time.

I think a lot of schools in the district could benefit from this technology. The Aeroseal team was able to work in coordination with all the other contractors on the job, ensuring that we maintained our extremely tight schedule. They also assisted us in securing a rebate from the local utility company that helped us stay within budget. In the end, this was an ideal solution to a potentially derailing problem. I look forward to assessing energy savings over the next year or two. In the meantime, we have heard nothing but positive feedback regarding the comfort of those using the new school building.”

Tom Hubbard, Bond Project Manager, Sunnyside School District

When contractors removed the ceiling tiles, they saw that the existing ductwork was in really bad shape. They wanted to replace all of the ductwork but it was simply out of the budget – and that’s when one of our engineering consultants suggested we look into using Aeroseal as an alternative. It proved to be much less expensive than replacing the ductwork and it took only a matter of days to complete the job so the school was able to open as scheduled.”

Cindy Bova, Energy Project Manager, Sunnyside School District

Aeroseal—The Technology:

Developed at Lawrence Berkeley National Laboratory in 1994.

Research for Aeroseal technology was partially funded by the U.S. Department of Energy.

Aeroseal is the only duct sealant technology that is applied from the inside of the duct system. It is delivered as a non-toxic aerosol mist that seeks out and plugs leaks.

Aeroseal has proven to be 95% effective at sealing air duct leaks.

Source: Aeroseal

Aspen Air Duct Cleaning is an approved Aeroseal Dealer, licensed and ensured, and a member of the National Air Duct Cleaners Association (NADCA) and National Organization of Remediators and Mold Inspectors (NORMI).

Please contact Aspen Air Duct Cleaning at 1-800-931-6653 for an Air Duct System Inspection and to learn more about how sealing air duct leaks can improve indoor air quality and reduce energy costs. Or email