Maryland has a new AC law for renters, but many Baltimore tenants are still left out

Summer in Baltimore means swimming pools, snowballs, and looking for any way to escape the heat.

As climate change fuels record-breaking temperatures and heat waves, a home without air conditioning can be a health hazard instead of a refuge. In Baltimore, heat-related emergency department visits to city hospitals have more than doubled in recent years, rising from 95 in 2023 to 210 in 2025.

For years, housing advocates have urged Maryland officials to treat air conditioning in rental housing as a basic safety issue — no different from access to clean water or heat in the winter.

“To me, air conditioning is not a luxury,” said Carol Ott, director of housing services at Economic Action Maryland Fund. “It’s a necessity, just like heat.”

Starting June 1, a new Maryland law, Senate Bill 12, began requiring some large apartment buildings to provide air conditioning. But the bill’s sponsors acknowledge the law’s impact will be limited at first, and could take years to reach many of the renters already facing extreme heat.

In a city with an affordable housing crisis, roughly half of residents live in rentals, and half of those renters struggle to afford their rent — making air conditioners and the utility bills needed to run them out of reach for many.

Majority-Black neighborhoods in the eastern and western parts of the city, known as the Black Butterfly, are especially vulnerable to extreme heat. The legacy of racist housing policies in these neighborhoods has created urban heat islands: temperatures can be as many as 10 degrees hotter than surrounding areas because of less tree cover, more pavement, and dense infrastructure. In those neighborhoods, heat can build indoors and linger after the sun goes down. For renters without reliable air conditioning, that can make a hot day dangerous.

Maryland’s heat-related death toll has climbed sharply in recent years, from nine deaths in 2023 to 27 in 2024 and 36 in 2025, according to state data. In 2025, three-quarters of heat-related deaths occurred indoors or in vehicles, underscoring the danger for people who cannot reliably escape the heat. The rise in deaths was concentrated during dangerous heat waves and among populations already at higher risk: older adults, people with cardiovascular disease, and people without reliable access to cooling.

In 2025, Maryland recorded nearly 1,700 emergency room visits and 1,645 emergency medical services calls for heat-related illness. Baltimore already recorded its first heat-related death this year.

Since the law went into effect, Baltimore has already seen dangerous temperatures: the city entered its first Code Red Extreme Heat Alert of the year on June 11 and 12, with temperatures reaching 98 degrees and the heat index passing 100.

While the legislation made Maryland one of the first states to set cooling standards for rentals, its limited scope provides little immediate relief for renters facing high heat this summer.

The law applies only to buildings with 10 or more units. It covers new construction and apartments that already provide cooling; starting October 1, it will also apply to units undergoing major electrical or heating renovations. Properties listed on the National Register of Historic Places are exempt. From June 1 through September 30, landlords must keep covered units at or below 80 degrees.

Matt Hill, managing attorney at civil rights law firm and advocacy organization Public Justice Center, said that while the bill is a good first step, extreme heat is already a serious housing issue in Baltimore.

“We’ve seen far too many clients who are essentially just roasting in these properties,” Hill said.

Only about one third of Baltimore City rental units — roughly 38,000 out of 128,000 — are in buildings with 10 or more units, the kind of housing that could eventually be covered by the law, according to 2023 census data. Statewide, less than half of rental units fall into that category. That means the majority of Baltimore renters live in smaller buildings and rowhomes — outside the law’s reach entirely.

Meanwhile, high heat is becoming increasingly dangerous. A 2026 Johns Hopkins study found that Baltimore sees an uptick in asthma-related emergency room visits in the weeks following nighttime heat waves, with Black Butterfly neighborhoods hit hardest. Researchers compared those visits with temperature data from the summers of 2017 to 2022 and found that the city’s Code Red Extreme Heat Alert system, which relies on daytime forecasts and citywide readings, can miss sharp differences in nighttime heat across Baltimore neighborhoods. Areas with the biggest nighttime temperature swings were more likely to see increases at nearby hospitals.

“I don’t think it’s overly dramatic to say there are life or death consequences, because people can have fatal asthma attacks, but it also affects quality of life, happiness, and a kid’s ability to enjoy childhood,” said Johns Hopkins professor Benjamin Zaitchik in a press release.

As summer heat becomes more dangerous for city residents, advocates say the bill does not go far enough to protect vulnerable renters.

The law does not include fines for landlords who fail to comply. Tenants must seek enforcement from their local housing department, and may still have to sue their landlord if air conditioning stops working and is not repaired.

The bill originally would have applied to buildings with four or more units. In an email to Baltimore Beat, the bill’s sponsor Sen. Chris West said the threshold was raised to 10 units to overcome opposition from owners of smaller apartment buildings.

The office of Del. Mary A. Lehman, another sponsor, said lawmakers made a compromise on the final day of the legislative session: raise the threshold to 10 units, but remove a provision that would have blocked local jurisdictions from passing stronger air conditioning laws of their own. The change left fewer renters covered by the state law, but preserved the ability of cities and counties to pass stronger protections. Now housing advocates want Baltimore to use that authority to pass more stringent air conditioning laws, like the ones already on the books in Montgomery County, which requires landlords to provide it, and Prince George’s County, which requires that any landlord-provided AC maintain temperatures no higher than 80 degrees between June 1 and September 30.

“In Baltimore City, way too many ‘small landlords’ are exempt from laws that protect the health and safety of tenants — and air conditioning is a health and safety service,” Ott said.