Obstacles and Challenges

In terms of general impediments to a more widespread Passivhaus adoption in North America, Judah points out that there are a number of misperceptions that still need to be demystified—for example, that Passivhaus buildings don’t incorporate enough glass or operable windows, and that the tight building enclosure creates air-quality issues.

Furthermore, there is a common misperception that Passivhaus buildings are unattractive. “Ultimately, Passivhaus buildings in Europe look great, and we need a few good-looking projects to be built here,” Piselli explains. “It feels a lot like the early days of LEED where people were initially skeptical, but it didn’t take long to catch on.”

Judah also sees a need for more competitive building products, more training on the construction side, and better legislation favoring Passivhaus.

As things stand, the U.S. government provides generous subsidies for fossil fuels, while energy efficiency and renewable energy have not benefited from a level playing field, according to Everhart.

Furthermore, Passivhaus designs can’t offer the same curb appeal as wind or photovoltaic systems. “Movement attracts attention, but insulation doesn’t move,” Everhart explains. “Perhaps it is human to be more interested in producing energy than saving it, but Passivhaus is measured in ‘negawatts’—the energy you don’t use. It is not glamorous but reliable, and we believe it has the lowest environmental life-cycle cost.”

“Until the playing field is level, Passivhaus may largely appeal to people with particular environmental, social, and/or philosophical values, in addition to economic return,” he adds.

What's In Store

Judging from the code’s orientation toward stricter energy requirements, as time goes on, Passivhaus is well poised to help building teams navigate toward this direction.

Image courtesy of Handel Architects

Although Passivhaus advocates would like to see more Passivhaus-certified products and more favorable legislation in North America, they anticipate that these highly energy efficient, resiliant designs—like Cornell Tech’s new residence tower—will continue to gain traction.

“There has been a slow adoption of this standard in the United States, but there is evidence in the latest version of the IBC that all construction is headed toward additional insulation and minimizing air-infiltration,” says Nettleton. “I think most buildings will be built this way in the near future.”

While project teams have access to various sustainable design programs and certifications, Zakrzewski sums it up by saying, “Passivhaus buildings are on another level.”

MEGA-PANEL SYSTEM SUPPORTS PASSIVHAUS AT CORNELL TECH

Handel Architects and Steven Winter Associates are working together to achieve an aggressive Passivhaus design goal for Cornell Tech’s new 26-story academic residence tower, part of the school’s new technology campus on Manhattan’s Roosevelt Island.

Mega panels were specified for the enclosure in lieu of a traditional curtain wall. With thermal bridges at the panel-to-panel joints and exterior finish support clips, the system delivers an overall R-value of 19. “Thermal bridging is significantly reduced through the use of nonconductive structural materials separating all metal from the building,” reports Deborah Moelis, AIA, senior associate, Handel Architects, New York.

Image courtesy of Handel Architects

Thermally broken construction, an airtight envelope, and high-performance triple glazing contribute to Cornell Tech’s Passivhaus certification for its high-rise residential tower.

The mega panels include triple glazed windows, installed in the factory to drastically increase quality control and support a highly sealed window, contributing to an airtight facade.

In terms of the overall facade system, the prefabricated metal panel system works as a thermally insulated blanket wrapping the building structure, thereby boosting thermal performance levels.

Enhancing the building’s aesthetics, the southwest exterior facade facing Manhattan opens to reveal a louver system that extends through the building’s full height. Serving as the building’s “gills,” the enclosed, louvered exterior space houses the facility’s heating and cooling equipment and enables the building to breathe.

Contributing to the residences’ indoor air quality, purified fresh air will be ducted into each bedroom and living room.

The Ornamental Metal Institute of New York is a not-for-profit association created to advance the interests of the architectural, ornamental, and miscellaneous metal industries by helping architects, engineers, developers, and construction managers transform designs into reality. www.ominy.org