Donald J. Trump is no green building enthusiast. Or so he professed a few years ago in a CNBC interview.

“You won’t have enough light in the winter, and you’re going to be extremely cold,” he recalled telling a friend who was moving into a sustainable office. “In the summer you’re going to be sweating at your desk.” Trump claimed the friend came back to him later to confess that Trump had been right.

The new president’s own properties give meat to his dismissive anecdote. A single unit in one of more than 50 buildings either owned by the Trump Organization or licensed to use the Trump name is publicly listed by U.S. Green Building Council as a candidate for LEED. That unit, 62C in Trump Tower International in Chicago, is seeking certification under LEED’s Interior Design and Construction standard.

Contrast Trump’s posture to that of the previous president. Over eight years, the Obama administration expanded or created dozens of programs for renewables, energy efficiency and green building, and the then-president served as their cheerleader-in-chief. Among the most notable: the Better Buildings Challenge, which put more than $5 billion in public and private money toward energy efficiency projects for some 34,000 properties.

But how much does Washington matter? Do the design and construction industries need favorable policies and the president’s bully pulpit to continue their march toward sustainability? The answer depends on where you sit.

Despite the potential loss in federal support, green building organizations express optimism.

“The green building industry is driven by market forces and will continue to grow,” Elizabeth Beardsley, senior policy counsel at the U.S. Green Building Council, said in response to written questions. “Moreover, incentives for private sector green building exist in many states, local governments and utilities, and are not directly affected by the presidential transition.”

International Living Future Institute CEO Amanda Sturgeon says the ILFI’s Living Building Challenge is well positioned because LBC growth is founded less on government assistance than on an enthusiastic leading edge of funders, owners, designers and builders.

“I think there’s an opportunity for us to get stronger,” Sturgeon says. “There could be a reaction where more people and organizations extend toward the most innovative solutions.”

Neither the White House press office nor the General Services Administration responded last week to requests for comment. It is a bit early for the administration to dig down into relatively obscure federal green building programs. But it’s also easy to see how reversals in federal support could slow progress on sustainable practices and technologies, as well as the number of actual projects.

Within hours of his inauguration, Trump provided a concrete example of what that pullback might look like. He blocked four executive orders Obama had signed to improve the efficiency of portable air conditioners, walk-in coolers and freezers, commercial boilers and uninterruptible power supplies.

While the president still could allow those rules to take effect, efficiency advocates worry that their immediate suspension bodes poorly. The delay could portend an ideologically driven effort to roll back the clock — despite a broad business consensus that efficiency standards level the playing field for responsible players.

Clean power backers express optimism that solar, wind and other technologies aren’t going to lose the foothold they’ve gained in the larger electricity market. But they’re also worried that cutbacks in federal support could make it harder to gain market share, as well as to advance technologically. One example: Could funding for the National Renewable Energy Lab, which partners with private companies to test improvements in photovoltaics and other clean energy technologies, be on the chopping block?

One direct policy change could reduce the role federal government plays in advancing green building. The General Services Administration requires “new construction and substantial renovation of Federally-owned facilities” to attain at least LEED Gold certification. That’s resulted in at least 154 LEED certifications over the last decade. Trump’s new administrator at the GSA, which owns and operates most federal buildings, could rescind that rule.

Separately, a 2015 executive order by Obama — mandating that federal buildings cut their energy use by 2.5 percent each year through 2025 — could be countermanded by Trump himself.

The prospect of reversals is likely to inspire some defensive lobbying. Leading manufacturers now have a vested interest in clean energy and efficiency, just as architects, engineers and builders have their own stakes in high-performance buildings and certification programs. But Trump’s leadership style makes it difficult to know which direction he’ll take on any given issue — regardless of pleas from business groups. Where some free market advocates see growth industries worthy of nurturing, key influencers within the new administration view incentivizing green buildings and clean energy as the government picking winners and losers. There’s also the argument that tax changes favorable to venture capital are more likely to spur innovation than are government subsidies.

“If the Trump administration only cares about results,” argues one prominent LEED critic, “we may actually do better at creating energy efficient buildings, because they will go with what works rather than earning plaques.”

USGBC’s Beardsley acknowledges that important programs — Energy Star and WaterSense, for example — “may receive some scrutiny or be impacted under the new Administration.” But, she argues, “nested” laws and rules will be hard to push aside — especially when they’re founded on bipartisan support for industry and for energy security.

It may seem paradoxical for Sturgeon to argue that the deeper green LBC could be even less vulnerable to a loss of federal support for green building.

“We’re getting a bit more aggressive anyway,” Sturgeon says. “Traditionally, we’re strong among nonprofits. But we’re doing more business development in the space of companies that are committed to being leaders by becoming early adopters.”

Some federal agencies have expressed interest in various aspects of regenerative design and construction — from net-positive energy to non-toxic building materials. But the LBC still receives almost all its support from the private sector (with modest government involvement coming from a handful of progressive localities). Sturgeon notes that LBC owners and funders have tended to be foundations, schools and nonprofits — with more recent interest from companies, such as Etsy and Google, that have very strong commitments to sustainability.

Those organizations tend to be less concerned about price points or government incentives than about modeling sustainable values and advancing green construction. (A prime example is the Kendeda Fund, which publishes this website and is funding the Living Building at Georgia Tech.)

Although still a small program, LBC has gained notoriety and momentum in less than a decade of existence. Annual LBC registrations climbed from 14 in 2010 to 77 in 2015, for a cumulative total of 310 (2016 numbers were still being compiled as we worked on this story). Sturgeon expects growth to continue as ILFI scales up tits business development program for the Living Building Challenge, as well as the Living Product Challenge and the Living Community Challenge.

She acknowledges that growth for a single program isn’t the same as transforming an entire sector of the economy. But, Sturgeon argues, that can serve as an advantage: “People can get lazy when everything’s going well. But a lot of professionals in the progressive building community see the Trump Administration as a threat to the progress we’ve made. So it’s sort of a kick in the pants. Sometimes, a culture needs to take several steps back to realize that they don’t want to go there again.”