Part of a wide expansion of applied science learning, as well as large bet on the New York tech scene, Cornell University’s under-construction campus on New York City’s Roosevelt Island is being marketed as an educational environment of the future. And amid the cutting-edge labs and classrooms where developments and discoveries are expected to take place, one building, a residential high-rise, may provide the most lessons for future administrators and developers
Designed by Handel Architects, the 270-foot-tall, 26-story Cornell Tech Residential high-rise will be one of the most energy-efficient buildings on this, or any, campus when it opens next year. Set to be the largest structure in the world built to the exacting passive house energy standards, which demands exceptional energy efficiency as a means to radically shrink a building’s environmental footprint, this new home for students and faculty will offer massive cost savings for the university. According to architect Gary Handel, the 350-unit structure is so efficient, residents in rooms facing the south will likely never need to turn on a heater, while those living on the north side of the building could "heat their space with a hair dryer." He believes the years of work his firm invested in devising the new design and construction methods needed to scale up passive house building will pay off, and not merely in lower utility bills for the life of the building.
"We like to use the analogy that by doing all this front-end work, we’re like a snow plow clearing the road," he says. "It’ll be a lot easier for everyone else to follow behind. Once we demonstrate you can do this, with both environmental benefits and a rational payback for developers, this type of building will become the standard for academic and dormitory construction."
Passive house construction achieves such a significant reduction in energy usage with tight, technically advanced building envelopes, guaranteeing that any energy spent heating or cooling the structure isn’t wasted. These structures are so tightly sealed that architects and builders need to introduce artificial air, via ventilators and HVAC systems, to maintain the constant circulation of fresh air. These building methods provide unexpected advantages to students; these dorms will not only be the quietest in the country, due to the thick walls, but boast the best air quality.
Passive House standards, as the name may suggest, have mostly been applied to residential projects, but increasingly, architects and designers are planning larger commercial structures with the same efficiency. The 16-story Allgemeine Angaben in Germany is currently the world’s tallest residential passive house structure, and a 20-story office tower opened in Vienna in 2013.
Building the Cornell Tech Residential offers new challenges for this type of construction, both due to cost and complexity. Building in a city may seem to add extra layers of difficulty, but the density of urban buildings—which means less exterior exposure per unit—actually makes it easier to achieve high efficiency. Once Handel Architects, in tandem with developers Related Properties and Hudson Companies, as well as the construction crews, figured out how to maintain an air-tight facade across all 26 stories, and oriented the building to decrease solar gain, the record-breaking project seemed more manageable.
"When everyone gets over the fear factor, they realize passive house is actually scalable and ideally suited for urban environments," says Handel.
One of the main challenges was creating an environmentally advanced structure that didn’t add exceptional upfront costs and raise the rental price of each unit. Cornell was adamant about keeping prices competitive for future students (the final tab, estimated at $115 million, should add just a 5 percent premium above a standard dorm of similar size). The solution included slightly smaller windows and a thick, high-tech facade, in this case, an exterior envelope up to 16 inches thick with two layers of steel stud construction filled with insulation, which are then thermally separated and air sealed. A louver system on the southwest face of the structure will contain the heating, cooling, and circulation equipment for the building, which will circulate refrigerant around each floor (since the structure is so air-tight and easy to warm, cooling becomes a much bigger energy challenge). To control the cost of fabricating this complicated exterior, the design team decided to utilize 36-foot-long prefab panels, building wall sections off-site to decrease costs and maintain the high level of quality control needed to erect the walls of a massive tower without any leaks.
"On most projects, the architects do drawings and give them to the contractor, then the contractor does their work, and then the architect complains and asks about the final product," says Handel. "We can’t do that here. It not only has to be designed well, but built well."
After years of design and development, the superstructure of the tower should top off next week, and panels are beginning to be installed. Handel projects the building will achieve a 77.5 percent reduction in total energy use; he’s currently working on integrating a system that allows students to see real-time visualizations of just how much power is being saved in their new home. Handel sees no limit to the expansion of passive house construction, especially considering the large cuts needed in energy and carbon emissions. His firm already has its eyes set on forthcoming projects and proposals, including a passive hotel in Chicago and a submission for a low-income passive senior center in New York, that offer challenging new use cases and cost requirements.
"It relies on doing a few things well, but it’s completely scalable," says Handel. "It’ll be fun to see if we can push the cost down even further."