The region’s air pollution regulators overwhelmingly approved the ban, which would take effect in several stages from 2027 through 2031 depending on the size and type of equipment. Notably, the measure does not target gas-burning stoves, which have emerged as a cultural flashpoint in the debate over phasing out in-home use of the fossil fuel.

The gas industry and many Republicans say gas bans raise costs for homeowners while infringing on their right to heat their homes and cook as they like. Climate activists consider replacing gas appliances with electric ones a necessary step for fighting climate change, and they see the Bay Area’s new rules as a way to do it.

The regulations from the Bay Area Air Quality Management District focus on furnaces and water heaters and the air pollution they create, specifically nitrogen oxides (NOx). Produced when gas is burned, NOx is a component of smog and can worsen asthma and cardiovascular problems. The district estimates gas-burning furnaces and water heater generate more NOx each year than all the region’s cars.  Water heaters and furnaces sold in the Bay Area will be required to emit no NOx by the implementation dates, effectively forcing homeowners to buy electric heaters or heat pumps. 

The requirement has prompted concern from some residents that, should their water heaters or furnaces abruptly break, they will be forced to pay more for an electric replacement — if they can find one readily available. District board member Ray Mueller said that while he supported the idea, the requirement could burden homeowners, particularly if switching to electric appliances forces them to upgrade their home’s electrical panel and wiring.

“Candidly, what I think is missing from this discussion is the fact that there is a middle class out there that is really hurting,” said Mueller, a San Mateo county supervisor who abstained from voting on the measure.

Most board members, however, said that by setting the requirement years into the future, the district would send a clear signal to the market to offer more heat pump and electric water heater models, bringing down the price. The measure also requires board members to take another look at market conditions two years before the first implementation deadline, which they can then adjust if needed. 

“Necessity is the mother of invention, so what we’re doing is creating necessity and the market will respond,” said board member Juan Gonzalez, mayor of the city of San Leandro.

Even with the measure in place, many gas-burning furnaces and water heaters in the Bay Area will continue running decades into the future, said Leah Louis-Prescott, with the RMI climate and energy think tank. Homeowners will still be able to repair their old, gas-burning appliances after 2031. 

“It’s making sure the consumer purchases a cleaner appliance and avoids locking in decades of pollution,” said Louis-Prescott, who is with RMI’s carbon-free buildings team. “It’s not so much a ban — it’s a gradual phase out, as your appliances break.”

The gas debate has raged for years in the Bay Area, home to more than 7 million people. Berkeley officials in 2019 passed the nation’s first ordinance banning gas hookups in new buildings. San Francisco and other cities nationwide followed suit, with New York City adopting its own ban in 2021 and Governor  Kathy Hochul this year calling for a statewide version. The gas industry and its political allies have pushed back, with at least 20 states passing laws that prevent their cities from blocking use of the fuel.