Why New Jersey's Older Classrooms Still Can't Stay Cool

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On May 19, 2026, with forecasters calling for record highs and heat index readings near 100 degrees, at least eight New Jersey school districts sent students home early, Patch reported. The list included Garfield in Bergen County, Wayne and Prospect Park in Passaic County, and Cranford, Scotch Plains-Fanwood and Union in Union County. The school year still had a month to run.

Tenafly has been weighing the same problem for a decade. A 2016 feasibility study estimated that central air conditioning in all six of the borough's public schools, including the electrical and building upgrades needed to support it, would cost about $17 million, and no action followed. In September 2024, Tenafly voters approved a $76.1 million school referendum by 12 votes, 1,199 to 1,187. The package replaces classroom ventilation units across the district, along with aging rooftop units and chillers at the high school, according to the district's project list. The list does not describe adding air conditioning to classrooms.

Tenafly priced central air for all six of its schools at about $17 million in 2016. The $76.1 million referendum voters approved in 2024 replaces ventilation and high school cooling equipment but does not list classroom air conditioning. Graphic: TownSquare. Sources: Tenafly Public Schools; Northern Valley Press. — Tenafly priced central air for all six of its schools at about $17 million in 2016. The $76.1 million referendum voters approved in 2024 replaces ventilation and high school cooling equipment but does not list classroom air conditioning. *Graphic: TownSquare. Sources: Tenafly Public Schools; Northern Valley Press.*

Cooling an older school turns out to be harder than buying air conditioners. The obstacles sit inside the walls, in the electrical room and in the way New Jersey pays for school buildings.

A Building Designed Around a Radiator

Many New Jersey schools were built when a building had one climate job, which was keeping people warm. A boiler in the basement heats water or makes steam, and pipes carry the heat to radiators or to unit ventilators. A unit ventilator is the metal cabinet under a classroom window. It pulls in outdoor air, filters and warms it, and blows it into the room. Most of Tenafly's were installed when its schools were built, the district says.

Cooling works in reverse. An air conditioner doesn't add cold to a room. It removes heat and dumps it outdoors. The key part is the compressor, a pump that squeezes a refrigerant so the fluid can soak up heat inside and release it outside. Compressors run on electricity, and a building full of them draws far more power than lights and computers do.

Older schools struggle on both counts. Central air in a modern school usually moves cooled air through ducts, the sheet-metal channels hidden above ceilings and inside walls. Load-bearing brick walls leave little room to add them, and cutting new channels through structural masonry is slow and expensive. Electrical capacity can be just as limiting. Panels sized for lighting and a few outlets cannot carry dozens of compressors, so a cooling project can set off a chain of upgrades to panels, wiring and switchgear. Switchgear is the heavy equipment that takes power from the utility and divides it across a building. Tenafly's 2016 estimate bundled in those electrical and building costs, a reminder of how much of a cooling project sits outside the cooling equipment.

Older schools were built to push heat in from a single boiler. Cooling means moving heat out of every room, and the compressors that do it need far more electricity. Illustration: TownSquare. — Older schools were built to push heat in from a single boiler. Cooling means moving heat out of every room, and the compressors that do it need far more electricity. *Illustration: TownSquare.*

The problem reaches well beyond New Jersey. A 2020 U.S. Government Accountability Office survey estimated that 41 percent of school districts nationwide needed to update or replace heating, ventilation and air conditioning systems in at least half their schools, about 36,000 schools in all.

Three Ways to Cool an Old Classroom

The cheapest fix is the one many teachers already know. A window air conditioner is a complete small cooling system in a box, with the compressor hanging outside the glass. Window units need no ductwork, and a district can add them one room at a time. Each unit needs its own electrical circuit, though, and window units block part of the window, run loudly and cool unevenly.

Ductless mini-splits are the more permanent version of the same idea. A mini-split separates the two halves of an air conditioner. A wall-mounted unit inside the classroom connects to a compressor outdoors through a thin bundle of refrigerant tubing and wiring that passes through a small hole in the wall. Without ducts, the masonry problem mostly disappears. Most mini-splits sold today are heat pumps, which can run in reverse to heat a room in winter, so a district replacing a worn-out boiler could use one set of equipment for both seasons. Mini-splits still draw real power, and in an older building the electrical upgrade usually has to come first.

The most ambitious option uses the ground itself. A few feet below the surface, the earth stays at a relatively constant temperature all year, cooler than summer air and warmer than winter air, according to the U.S. Department of Energy. A geothermal heat pump system circulates water through pipes in boreholes about four inches wide, drilled 100 to 400 feet deep and spaced about 20 feet apart. The heat pump uses that steady underground temperature as its starting point, so it needs less electricity than a system pulling heat from freezing January air or pushing it into 95-degree June air. The catch is the upfront bill. DOE says installation can cost several times as much as an air-source system of the same capacity, with the difference often recovered through energy savings in 5 to 10 years. The underground loop is expected to last more than 50 years.

Geothermal boreholes trade heat with ground that stays at a steady temperature all year. Drilling costs more up front, but the underground loop is expected to last more than 50 years. Illustration: TownSquare. Sources: U.S. Department of Energy; ACHR News. — Geothermal boreholes trade heat with ground that stays at a steady temperature all year. Drilling costs more up front, but the underground loop is expected to last more than 50 years. *Illustration: TownSquare. Sources: U.S. Department of Energy; ACHR News.*

New Jersey's geology can support the approach. Stockton University in Galloway switched its campus to geothermal heating and cooling in the winter of 1993-94, using about 400 wells drilled roughly 425 feet deep. Larger shared systems, where one underground well field serves several buildings, are still in the study stage. Engineers call them thermal energy networks. A report by Rutgers' Center for Urban Policy Research for the state Board of Public Utilities, published in February 2026 under a 2023 state law, examined their feasibility and recommended pilot programs, financial incentives and legislative changes to get past cost and regulatory barriers.

Each option trades upfront cost against noise, electrical demand and how long the equipment lasts. Graphic: TownSquare. Geothermal figures: U.S. Department of Energy. — Each option trades upfront cost against noise, electrical demand and how long the equipment lasts. *Graphic: TownSquare. Geothermal figures: U.S. Department of Energy.*

Until one of those fixes arrives, districts rely on fans, portable coolers and heat-day schedules like the early dismissals in May.

Why the Temperature Matters

Heat does more than make a room uncomfortable. Economists Joshua Goodman, Michael Hurwitz, Jisung Park and Jonathan Smith studied more than 10 million students who took the PSAT and found that each 1-degree Fahrenheit increase in average school-year temperature reduced learning that year by about 1 percent, according to a FutureEd summary of their National Bureau of Economic Research paper. Air conditioning largely offset the loss. The effect was three times as large for Black and Hispanic students as for white students, and about three times as large for students in the lowest-income ZIP codes as for those in the highest.

In a study of more than 10 million PSAT takers, hotter school years meant less learning. The effect was about three times as large for Black, Hispanic and lower-income students.Graphic: TownSquare. Source: Goodman, Hurwitz, Park and Smith, "Heat and Learning" (NBER).

New Jersey Education Association President Sean Spiller made the case in plainer terms in 2022. "Adults expect their homes, offices and cars to be air conditioned. We shouldn't tolerate anything less for our children," he told New Jersey 101.5.

Who Pays Depends on Which District You're In

New Jersey runs school construction through two separate systems. In 31 districts, mostly higher-poverty urban districts, the state Schools Development Authority plans, funds and builds major projects itself. Everywhere else, a district usually has to win a local bond referendum, and the state then covers at least 40 percent of the costs it deems eligible, through debt service aid or grants, according to the state Department of Education.

In the 31 SDA districts, the state builds projects itself. Everywhere else, cooling usually needs a voter-approved bond, with the state covering part of the eligible cost. Graphic: TownSquare. Sources: NJSDA; NJ Department of Education; Tenafly Public Schools. — In the 31 SDA districts, the state builds projects itself. Everywhere else, cooling usually needs a voter-approved bond, with the state covering part of the eligible cost. *Graphic: TownSquare. Sources: NJSDA; NJ Department of Education; Tenafly Public Schools.*

The word "eligible" carries a lot of weight there. Tenafly's ballot question cited the 40 percent rate, but the district projected about $16.5 million in state aid on its $76.1 million plan, roughly 22 percent of the total, and an added $881 a year in school taxes on an average home, according to its referendum FAQ.

State capital money has come in rounds rather than as a steady stream. In September 2023, the state approved nearly $450 million in grants for 261 districts outside the SDA system. A $75 million round in January 2024 set aside $50 million for SDA districts and $25 million for everyone else, covering HVAC repair or replacement alongside roofing, masonry and security work. The FY2026 budget gave the SDA another $50 million for urgent repairs in its districts, and the authority told legislators this spring that its FY2027 allocation had risen to $400 million. In the same budget response, the SDA estimated its priority needs at more than $6 billion to $7 billion and said currently available money is not enough to fund any of them.

Recent state rounds run in the tens to hundreds of millions of dollars. The SDA's own estimate of priority needs in its 31 districts tops $6 billion. Graphic: TownSquare. Sources: NJSDA FY2027 budget response; NJ Department of Education. — Recent state rounds run in the tens to hundreds of millions of dollars. The SDA's own estimate of priority needs in its 31 districts tops $6 billion. *Graphic: TownSquare. Sources: NJSDA FY2027 budget response; NJ Department of Education.*

Clean-energy money offers another route, with conditions attached. The New Jersey Economic Development Authority's NJ Cool pilot, paid for with proceeds from the Regional Greenhouse Gas Initiative, a multistate carbon market, covers half the eligible cost of heat pump projects, in grants from $50,000 to $1 million. Public schools can apply. The first round, budgeted at $15 million and expandable to $30 million, opened only in Atlantic City, Edison and Newark before expanding in May 2025 to the state's designated overburdened communities, areas with high shares of low-income, minority or limited-English households.

A $25 million second phase has been approved but had not opened for applications as of late October 2026. Its projects must pair electric heating or cooling with on-site solar, geothermal or battery storage, cost at least $100,000 and sit inside a mapped overburdened or adjacent neighborhood. Schools outside those areas cannot apply.

What's Still Unresolved

New Jersey sets no maximum classroom temperature. The closest rule, a state indoor air quality standard for public workplaces, requires an employer only to check that the HVAC system is working when temperatures in office buildings fall outside 68 to 79 degrees. Nothing in the rule requires a building to have cooling.

Lawmakers have tried to change that for years. In November 2018, the Assembly passed a bill from Assembly members Mila Jasey and Angela McKnight requiring districts to adopt temperature policies, but it stalled in the Senate. A version returned in 2022. The current bill, S3246, introduced Feb. 2, 2026, by Sens. Shirley Turner and Angela McKnight, would require every board of education to adopt temperature control standards and a protocol for rooms found unfit for learning. It sets no numeric limit, includes no money for equipment and sits in the Senate Education Committee.

Without a mandate or a dedicated funding stream, cooling competes with roofs, boilers and enrollment growth in each district's capital plan. In the SDA's 31 districts, the timeline depends on state appropriations. In the rest, it depends on voters, and in Tenafly the margin was 12 votes.

Residents have more say than they might expect. Every district must update its long-range facilities plan with the Department of Education at least once every five years, and boards debate capital projects and referendum proposals at public meetings.

When a district plans to replace boilers or classroom ventilators, parents and taxpayers can ask whether equipment that also cools was considered, since whatever goes in will likely stay for decades. Families can ask for their district's written heat-day policy. Statewide, S3246's sponsors and the Senate Education Committee are the place to weigh in on whether New Jersey should set a temperature standard, and who should pay to meet it.