Net Zero Buildings Expand in Design Options and Capabilities

The built environment sector depletes 35 percent of the world’s energy and spews 38 percent of energy-related carbon emissions. That footprint will likely double by 2060, projects the World Green Building Council.

As climate conversations amplify, the pressure is on for the industry to change course fast, which is propelling an accelerating movement: the introduction of net zero buildings. These pioneering projects are popping up around the world. And as stakeholders learn more about what is possible to bolster impact, more design features and approaches come online.

As the transformations happen, even just what “net zero” means continues to evolve. At first the concept was fairly straightforward: balancing the amount of energy taken from the grid with the amount of renewable energy generated on site to net out to zero.

“You’ve taken from the grid and given back as much or more. That was the original concept, but now there is a focus on emissions associated with that energy,” says Elizabeth Beardsley, senior policy counsel at the U.S. Green Building Council, a nonprofit best known for its Leadership in Energy and Environmental Design (LEED) certifications.

Accounting for energy’s carbon intensity rather than just the energy itself means looking deeper. Now details matter like whether buildings draw on the grid during peak hours. Utilities use more fossil fuels when demand spikes, as renewable energy is in shorter supply.

Now attention is also turning to embodied carbon, which is emissions associated with the materials and construction processes needed to build and renovate structures. Looking at embodied carbon entails considering every step from extraction, to manufacturing and installation, to disposal. 

While net zero focuses mainly on energy and carbon emissions, there’s another concept in the sustainable built space: green buildings, which take a more holistic approach. The strategy considers energy, water, site development, and indoor air quality, among impact areas.

But as net zero gains traction, it continues to take form, and new certifications with more focus areas have come online.  The U.S. Green Building Council now offers LEED Zero certifications that consider not only energy and carbon emissions, but water use and waste generation.

Kevin Bates, founder of Sharp Development Company, retrofits commercial buildings to net zero energy.

He takes a holistic, integrative design approach. That means considering how every decision ultimately impacts others.

“You are trying to find the place where efficacy of cost and overall benefit intersect to maximize the value of reduced energy use while minimizing expense,” he says.

He starts out by taking everything he can get from nature for free, but there is still plenty that has to balance out. There are many details to weigh in on.

Here’s a scenario:

Glass gives more natural light, cutting down on artificial lighting. But it also gives more heat gain than an insulated wall, which may require a larger HVAC system. So, he installs more solar to offset that extra energy.

Still, he says “Most of what we do is pretty simple stuff.

“It’s natural light to reduce electricity use. It’s a well-insulated envelope to lower heating and cooling needs. It’s ceiling fans to move air in the summer so you can keep the building at about 75 degrees. It’s exposing concrete walls and using that thermal mass to absorb heat in the day. Then you can open windows and cool those surfaces at night.” 

Bates finds that doing net zero retrofits is more profitable than renovating to meet minimum code. While he may spend more upfront, there’s payback.

Pointing to one of his first projects, he says he spent $49.84 a square foot more to build to net zero energy than had he renovated to minimum code.

But he reduced his operating expenses. And the building leased quicker and at a higher rent than previously achieved in that market at that time. Ultimately, he says, for every dollar he spent over what he would have had he not upgraded, he got back three dollars per square foot.

Governments are starting to incorporate net zero in their policies.

“Industry led the way, and then the federal government, especially in the last several years, has taken decarbonizing steps. Now states are picking up on this,” Beardsley says.

The federal government is decarbonizing its own portfolio as well as funding green building and net zero projects.

Each agency has its own policy. The General Services Administration for example requires its projects to certify to LEED Gold.  And one standout funding initiative is a Department of Housing and Urban Development retrofit program; it incorporates ideas for achieving both net zero and green building status.

States that are following suit are implementing a gamut of policies. Like the federal government, they are setting up green building programs for their portfolios. They are establishing building codes that align close to net zero. And some require property owners to measure and report energy and water usage to identify patterns and opportunity to improve.

Buy in comes from all around.

“Offices and housing, especially for low-rise developments, have a lot of net zero projects happening,” Beardsley says.

“With pressure and awareness of the crisis with climate change we’ve also seen a proliferation of corporate commitments to net-zero buildings.”

And she’s seen interest from schools.

“[In education] it’s a unique opportunity to imagine the future, and net zero schools can be a part of the learning curriculum,” she says.

The Joyce Centre for Partnership & Innovation at Mohawk College was Canada’s first zero carbon-certified building under the Canada Green Building Council’s program.

The 96,000-square-foot, seven-story structure incorporates features such as an expansive green roof; a massive solar panel array generating up to 721,000 kWh of renewable electricity a year; and a geo-exchange system to remove and store heat during the summer, which is used to warm the building in the winter.

The project represented a great opportunity to reinforce the school’s teaching and learning aspirations, says Anthony Cupido, research chair, Sustainable Building Technologies, Mohawk College.

Teaching spaces are grouped around a social hub atrium. These high-capacity spaces converge to allow the flow of students to interact around a café, lounge spaces, and private study areas.

“Students have access to every level of the building, from the solar thermal array on the roof to the mechanical room, and the sub-basement water room. They get hands-on learning in how to operate, monitor, and maintain a zero carbon building through experiential learning,” Cupido says.

The Joyce Centre also serves as a demonstration site for industry partners looking to incorporate zero carbon technologies into their buildings. These partners work alongside students and faculty on applied renewable energy research projects.

Global initiatives are pooling stakeholders from around the world to catalyze collective action.

Through the Buildings Breakthrough, under the auspice of the United Nations Conference of the Parties (COP), 28 countries have committed to accelerating decarbonization of the built environment. Through the World Green Building Council’s Net Zero Carbon Buildings Commitment, businesses, governments, and green building organizations have made a similar pledge.

Experts watching this space see more opportunity on the way as policies emerge and funding opens up. Domestically, the Inflation Reduction Act (IRA) offers sweeping incentives for developers, contractors, and property owners. There is a tax credit to decarbonize buildings. And there are incentives for efficiency upgrades to commercial buildings, homes, and public buildings. One program has a higher tier payment for “zero energy-ready” homes.

Says Beardsley: “Interest in net zero emission buildings is starting to become normalized, and we are looking ahead to help owners focus on the next issues, which will be biodiversity and water resources.  It’s exciting to be part of the transformation that leaders in the building industry have been working on for 30 years.”