What the candidates for mayor have to say about New York’s landmark climate housing law

As New York City approaches Election Day to select its next mayor, we’ve spent the last nearly ten months watching candi­dates state and debate their stances on every­thing from public safety, to housing, to which parades have the right to exist. Yet one topic that’s often been over­looked is the city’s clean energy tran­si­tion: What will become of the climate laws New York has passed so far, and will the next mayor advance these goals, or stall them? 

In the final debates leading up to the start of early voting on October 25, the candi­dates were asked just a few glancing ques­tions about their plans regarding Local Law 97 (LL97), New York City’s land­mark climate housing law. Here, Skylight has compiled a compre­hen­sive accounting of where the candi­dates stand, based on all they’ve said on the campaign trail. Democratic nominee Zohran Mamdani and inde­pen­dent candi­date Andrew Cuomo have stated that they support the law, but differ in their views on its imple­men­ta­tion; Republican candi­date Curtis Sliwa has stated that he is opposed to it. These answers are not so cut and dry as they might seem, and who we elect will have an outsized impact on the city’s ability to meet its Net Zero goals on time. 

First, for context: What is Local Law 97?

Local Law 97 (LL97) is a 2019 law that requires build­ings larger than 25,000 square feet to begin the process of decar­boniza­tion, or reducing the amount of green­house gas (GHG) emis­sions produced by burning fossil fuels. The law was put in place because build­ings are respon­sible for over two-thirds of New York City’s carbon emis­sions. LL97 aims to nudge our biggest build­ings, which are the largest carbon contrib­u­tors, to start over­hauling their oper­a­tions, with a goal of reducing the city’s overall GHG emis­sions to net zero by 2050.

Many resi­den­tial build­ings have already risen to the chal­lenge of tran­si­tioning away from oil and gas, often led by home­owners who are espe­cially animated about clean tech­nology, climate change, and conser­va­tion. Notwithstanding early progress, the road to LL97 compli­ance for much of New York City’s aging housing stock is both diffi­cult and costly; many co-ops in partic­ular will ​“face signif­i­cant diffi­cul­ties paying for the system upgrades that LL97 will require,” according to a recent report by the Urban Land Institute. In the years since it’s passed, some stake­holders in New York City real estate have orga­nized to slow down the imple­men­ta­tion time­line for the law. In response to this advo­cacy, members of the city council have proposed new legis­la­tion such as Intro 772, which would allow outdoor green space to count toward a building’s overall square footage and thereby reducing the total carbon emis­sions per square foot without any changes to the building’s use of oil and gas. Others have sued unsuc­cess­fully to repeal LL97 alto­gether.

One common miscon­cep­tion about LL97 is that it will force all build­ings to fully elec­trify, leaving fuel oil and natural gas behind entirely. Some tactics for decar­boniza­tion do involve fully elec­tri­fying heating and cooling — heat pumps are a widely-discussed option — but, as Skylight docu­ments, there are many other ways to cut building emis­sions. Some involve simpler fixes, like installing LED lighting; or focusing on the effi­ciency of existing systems by installing a building manage­ment system to closely control boiler activity; others have re-clad their façade, added insu­lating covers to their radi­a­tors, and adopted hybrid solu­tions that allowed them to add clean energy heating and cooling while contin­uing to use their gas-fueled boilers. 

Despite contention over the law’s future, most build­ings which it covers have in some way responded to it so far: According to POLITICO, the Department of Buildings reported that 94 percent of covered build­ings had either filed their LL97 reports, requested an exten­sion, or begun working with the agency to figure out their route to compli­ance by the begin­ning of October. 

Read more in Skylight’s full explainer about LL97.

NYC mayoral candidates’ stance on Local Law 97, at a glance

While the clean energy tran­si­tion has not been a major topic in the mayoral campaign, the candi­dates’ posi­tions on New York City climate policy comes down to two key ques­tions: Whether they support the contin­u­a­tion of the laws at the core of the city’s plans to reduce carbon emis­sions dramat­i­cally over the next fifteen years; and whether they support extending the dead­lines for action along the way. Here’s an overview of where each candi­date stands.

Zohran Mamdani’s plan for Local Law 97: Uphold our climate commitments

When fron­trunner Mamdani first addressed ques­tions about LL97 at a mayoral forum in February 2025, he spoke fiercely about New York City being in an ​“exis­ten­tial moment of our climate crisis,” mentioning his widely-circu­lated promise to freeze the rent in rent-stabi­lized housing and empha­sizing that doing so, along with imple­menting LL97 fully, would mean ​“taking on the real estate industry.”

He has not wavered in his convic­tion that LL97 must be imple­mented, but since then, his messaging has become more specific — and sympa­thetic to the inter­ests of the people for whom this law poses real costs. ​“It is right now easier to pay the fine than to actu­ally comply with this legis­la­tion,” he told atten­dees at the final debate on October 22. ​“We have to ensure that we make it easier for condo and co-op owners to follow these laws.”

He went on to detail his plan for helping resi­den­tial owners comply, which centers around a more atten­tive exten­sion of aid from the govern­ment. He proposed extending the J‑51 R tax abate­ment, a tax break for build­ings that have taken on large-scale capital improve­ments that is set to expire at the end of next year, and elim­i­nating its appli­ca­tion fees, currently priced at $1000 for an initial appli­ca­tion, plus $75 per unit over six units. He also proposed creating a ​“one-stop shop in city govern­ment” that would be in charge of procuring clean energy tech in bulk to drive down prices: ​“We’ve seen this happen before with clean energy work that’s been done in Woodside houses,” he said at the final debate, refer­ring to NYCHA’s Clean Heat for All chal­lenge, which brought brand-new heat pump tech­nology invented specially for this purpose to its Woodside housing project. (Read more about how the chal­lenge worked in Skylight’s eighth edition.)

A memo outlining Mamdani’s plan for home­owners says that he would have this one-stop shop run out of the NYC Accelerator, which already exists to promote resources and incen­tives to home­owners, but which the memo calls ​“under­staffed and under­funded” in its current state. According to the memo, it is Mamdani’s view that ​“it’s cheaper for the Accelerator to buy 10,000 heat pumps and sell them to New Yorkers at cost than it is for 10,000 house­holds to buy that same heat pump at retail prices.”

Overall, Mamdani’s plan is to uphold the city’s commit­ment to LL97, while making compli­ance easier for co-ops and condos by making incen­tives more acces­sible and driving down the cost of expen­sive upgrades.

Andrew R. Cuomo’s plan for Local Law 97: Implement it while ​“deal[ing] with reality”

Cuomo has been signif­i­cantly less direct in stating his plan for the future of what to do with LL97. In the first debate for the general mayoral elec­tion on October 16, Cuomo said affir­ma­tively that he supported LL97, with the caveat that ​“imple­menting the law is going to be the key.” 

“It has to be done in a way that isn’t so disrup­tive to busi­nesses and resi­dences that they just give up and pay the fine and don’t even try to comply, which is what is going to happen now,” he said. ​“It will be cheaper for them to pay the fine than comply. And that obvi­ously will accom­plish nothing. So yes, I support the law; yes, we have to imple­ment it; but we have to imple­ment it in a way that is feasible.”

What ​“feasible” means to Cuomo and his campaign is not entirely clear. Crain’s reported in May that Cuomo attended a meeting with a coali­tion of co-op board members where he said that he would be ​“open to modi­fying New York City’s land­mark climate law that restricts building carbon emis­sions to go easier on co-op build­ings that are strug­gling to pay for building retro­fits to comply with the law,” according to two people who were there. Then, in a state­ment to the New York Times in July, spokesman Rich Azzopardi said that Cuomo ​“wants to fix ​‘imple­men­ta­tion chal­lenges’ by providing more support for building owners, including hard­ship waivers.” 

Still, when pushed by the moder­ator at the October 22 debate to expand on what he meant by offering addi­tional flex­i­bility to home­owners, Cuomo hedged, saying, ​“It’s going to be timing, and what do we mean, and can it be phased in.”

In 2021 as governor of New York, Cuomo supported the addi­tion of Renewable Energy Credits (RECs) to LL97, intended to soften the law by giving build­ings the ability to purchase credits in order to avoid fines. 

In several of the debates, Republican nominee Curtis Sliwa also took pains to point out that Cuomo’s embrace of LL97 might run counter to the prece­dent he set when he shut down Indian Point, the nuclear power plant supplying signif­i­cant carbon-free elec­tricity to the city’s grid, in 2021, thereby neces­si­tating a rebound of gas use to generate elec­trical power for New York City and pushing emis­sions up by 22 percent. In response, Cuomo main­tained that he took action out of concern for public safety. 

Curtis Sliwa’s plan for Local Law 97: Repeal it

Sliwa, at the time of publi­ca­tion running in a distant third place, has been unwa­vering in his oppo­si­tion to LL97. In a state­ment to Skylight, Daniel Kurzyna, campaign spokesperson for Sliwa, called LL97 a ​“disas­trous law,” writing: ​“Curtis Sliwa is the only candi­date in this race who is fully opposed to Local Law 97 and has pledged to direct his agency heads to block its enforcement.”

“Now we’re going to force condo and co-op owners to elec­trify?” Sliwa asked, incred­u­lous, at the October 16 mayoral debate, refer­encing the miscon­cep­tion that LL97 forces elec­tri­fi­ca­tion. ​“Maintenance fees will go up 30 percent. These people will be leaving their condos and co-ops. They need relief. When I’m mayor, I slow that process down. We need our co-op owners and condo owners to stay in New York.”

According to his plan for the first 100 days of his mayor­ship, blocking enforce­ment and slowing down the LL97 process would entail first halting imple­men­ta­tion of the law. This would look like a collab­o­ra­tive effort between various city­wide agen­cies to pause all penal­ties, give exten­sions for ​“good-faith actors” attempting to comply who have signif­i­cant road­blocks in their way, and lead an impact audit as well as a ​“tech­nical assis­tance program.

The campaigns of Zohran Mamdani and Andrew R. Cuomo did not respond to requests for comment.