Schools across Colorado began opening for the fall semester in the middle of August, with daytime temperatures reaching into the 90s in some places. Tens of thousands of Colorado public school students attend school in buildings with no air conditioning in their classrooms, and often—especially in buildings that are many decades old—no air conditioning in the building whatsoever.
“I end many days in the late summer, early fall and late spring earnestly checking the next day’s weather,” says Trena Marsal, executive director of facility management at Denver Public Schools (DPS).
Mira Van Dyke, a 7th grader enrolled in a Denver public school, and her sister Maeve, a 5th grader, have always gone to school without air conditioning, according to the girls.
“It’s just really hot,” says Mira. “It’s hard to pay attention in class. In the morning, it’s a lot cooler but in the afternoon, it gets really hot again.”
Mira says the heat can make her feel “really tired, and sometimes it’s hotter inside than outside, and teachers still expect you to pay attention.” The girls and their classmates attempt to cool off with frequent water breaks and standing in front of fans.
There is little doubt that air temperature can impact students’ ability to learn. A 2018 study by researchers at the Harvard T.H. Chan School of Public Health found that students who lived in dormitories without air conditioning during a heat wave performed worse on a series of cognitive tests compared with students who lived in air-conditioned dorms.
A 2018 National Bureau of Economic Research working paper detailed the urgency and benefit of climate control in classrooms. Researchers found that, on average, a one-degree increase in school-year temperature leads to a 1% learning loss—with impacts up to three times as damaging for students who are Black, Hispanic or living in the lowest-income ZIP codes.
“Historically, air conditioning has not been thought of as an equity issue,” says Jonathan Smith, PhD, an associate professor of economics at Georgia State University and one of the NBER study authors. “Our report showed that this is happening now, at a time when climate change is expected to cause extreme heat, and students of color are more likely to attend schools that don’t have air conditioning. We were able to show that physical inequity can lead to other inequities.
“I can’t say for sure what it means for these students’ health and well-being,” adds Smith, “but it stands to reason that it’s something to be concerned about.”
There is also an environmental justice issue to consider.
“For students with no access to air conditioning at home, there’s no respite to the heat whatsoever on the hottest days,” says Stephanie Malin, PhD, an environmental sociologist at Colorado State University.
Because K-12 education in the state is largely decentralized, there is no comprehensive list of how many Colorado public schools partially or completely lack air conditioning. But conversations with facility managers, school board members, academics and consultants across the state indicate the challenge is widespread.
“Hot days mean we need to open windows at night and use the ventilation systems to remove hot air from the classrooms and bring in cool nighttime air, which makes the classrooms cooler in the morning,” Marsal of DPS says. “On very hot days, however, that cooler air may only last until about noon. We also position fans in hallways and classrooms.”
A $795 million, four-year bond project passed by Denver voters in 2020 provided funding for air conditioning in 24 Denver public schools out of 55 that were not yet air conditioned. As of the end of August, the district had completed installations at seven schools; another eight schools are currently undergoing upgrades; and nine more are slated for upgrades in the next couple of years.
That means 31 DPS schools will still lack air conditioning.
COVID-19 pandemic federal funds the school district received—part of almost $200 billion nationwide—for ventilation improvement are being used to upgrade schools from pneumatic to digital controls and sensors. Marsal says the improvements provide more data analytics on the indoor temperature; faster alerts to increases in temperature; and quicker decisions on extra cooling efforts, or even the need for an early release from school because it’s just too hot to study.
“The COVID-related funds weren’t available just to add air conditioning, but could be used if schools were installing new HVAC systems or upgrading them,” explains Josh Higgins, maintenance director of the Eaton school district and vice president of the Colorado School Plant Managers Association.
Robert Lawson, executive director of facilities and construction for Pueblo School District 60, says the district has used about $28 million in federal pandemic funding to address air quality issues in four schools, including installing air conditioning and filtration. With the new funding, the district was able to purchase “some of the best HVAC systems out there,” says Lawson. Three district schools are now left without air conditioning, though two different streams of funding will pay for two of the schools to add A/C next year.
Even with the unexpected pandemic funding, many districts still have schools with no air conditioning at all. While an earlier bond provided funding for all five of Eaton’s schools to be air conditioned, Higgins says 20 of 53 schools at the last district he worked at, in nearby Fort Collins, are still without air conditioning.
Multiple school officials and experts interviewed for this story estimate that tens of thousands of Colorado public school students now face sweltering heat during approximately 40 school days (more than 20% of classroom days on many school calendars) in late spring, early summer and early fall, as well as during summer sessions.
A lack of air conditioning at schools isn’t limited to Colorado, of course. A 2020 study by the U.S. Government Accountability Office (GAO) estimated that close to half of schools in the country need to update or replace HVAC (heat, ventilation and air conditioning) systems.
Costs to install a new air conditioning system can start at $5 million for elementary schools—the price tag to install air conditioning at a 50,000 square-foot school in Pueblo recently, according to Lawson—and run as high as $15 million for a high school, which tends to have more rooms and space. Additionally, “older buildings often need asbestos remediation, which can add to the cost,” says Lawson.
The “upgrades” some schools made using pandemic funds can be misleading. Some schools chose to upgrade their cooling systems only with new fans or filters, but no air conditioning, says Paul Chinowsky, PhD, a professor of civil engineering at University of Colorado Boulder and former director of the university’s environmental design program. But neither fans nor filters “make an appreciable difference on cooling,” he says.
Even with available funding, some school boards still see air conditioning as a luxury and don’t support expenditures for what they see as just a few hot days a year, according to Chinowsky. “Our research shows that with temperatures increasing, what was a few days when board members were students could be whole months that students are in school—May, June, August, September—within five years,” he says.
Costs can also be more than just installing and retrofitting the systems, according to the GAO report, which found that updating pipes and insulation alone can cost up to $1 million per school; without doing such an upgrade simultaneous to a HVAC system, schools risk worse air quality and mold formation from moisture and condensation problems. And while federal funding has helped some schools get air conditioning sooner than predicted, Chinowsky says many schools have not built in maintenance and repair costs—so if and when those systems break down, “we’re right back where we started in terms of heat and its impacts.”
School buildings generally stand for 60 years before they are replaced, according to a 1999 report by the National Center for Education Statistics; some Colorado public schools are older than that. (Higgins says one school in his district was built in 1928, and only first got air conditioning this year.) Schools built decades ago are unlikely to have air conditioning since school generally used to start later in the calendar year, and average temperatures were cooler.
That has all changed. According to a 2022 report from the National Oceanic and Atmospheric Administration, average temperatures in Colorado have risen about 2.5°F since the beginning of the 20th century. Six of the eight warmest years on record for Colorado have occurred since 2012, and in addition to the overall trend of higher average temperatures, the number of very hot days has been above average since 2000.
Chinowsky says the optimal classroom temperature is usually 72 degrees, “but especially in eastern Colorado, there is no way to do that on hot days without air conditioning.”
Last year, the school board in the Thompson School District in Loveland was informed that providing air conditioning at every school in the district that lacked it would cost $80 million—an impossibility for a district that has, at most, $1 million each year for all capital projects, according to Todd Piccone, the school district’s chief operating officer. Piccone and others say generally the only funding options are grants and bond issues, which raise funds by increasing property taxes.
Maintenance is expensive, too. A report last year by the Center for Climate Integrity found that “as temperatures have risen, so have operations and maintenance costs, a process that will continue far into the future as the climate continues to heat up.” The report also found that Colorado is one of 10 states that will face more than $1 billion each in new cooling equipment costs by 2025.
To address long-term viability concerns, Boulder Valley School District coupled an energy audit and sustainability measures for each school that added air conditioning, says Mandy Redfield, a project manager for the district. She holds out the Broomfield Heights Middle School as a success story: The school added air conditioning in 2016, and a subsequent energy audit found that energy use and costs were lower after the air conditioning was installed than before, by also adding a number of energy-efficient measures such as increased roof insulation, new windows, upgraded lighting and other improvements as part of a comprehensive overhaul.
School leaders and policy makers need “finesse to sell” the notion of air conditioning, says one school district official. For example, having information from other districts that have recently added air conditioning and have fewer teacher and student absences “is the type of data needed to push this agenda forward.”
Fifty-two out of 56 Boulder Valley school buildings now have air conditioning, including seven schools that received it in 2021. (The schools without air conditioning are at higher elevations that don’t get as warm.) In research conducted for the 2014 bond campaign that funded the HVAC upgrades, classroom temperature surveys routinely captured readings of 80 degrees or higher.
While the Thompson School District has yet to figure out how it will pay to air condition all of its schools, it now knows jerry-rigging won’t work. Last year, the district put residential air conditioning units in some classrooms, but data collected by the district found they didn’t effectively cool the spaces.
Many other schools have also found that alternatives to centralized air conditioning often just don’t help. Opening the windows at night to draw out the hot air, so at least the morning classes can be more comfortable, is a common strategy, says Barb Clementi, a board member and past board president of Pueblo School District 60.
“But that doesn’t work at schools in… neighborhoods where theft, vandalism or safety is a concern if school windows are left open overnight, or when wildfire smoke is too dense to keep the windows open,” Clementi adds.
Amie Baca-Oehlert, president of the Colorado Education Association, says the issue is starting to get more attention as temperatures continue to rise and the fall school term starts earlier for some districts. The pandemic also brought the issue front and center for some districts, says Baca-Oehlert, especially in school buildings with windows that don’t open, or that had outdated air ventilation systems.
“I’m not sure how many people outside schools realize how underfunded schools are,” says Baca-Oehlert. Many schools, she says, simply don’t have the funds to install air conditioning: “They have to just do as best as they can with fans and water stations.”