Loyola University Information Commons
The Total Package: A glass box integrates passive and active technologies, demonstrating that transparency and energy efficiency arenít always at odds
When administrators and trustees at Chicago’s Loyola University began envisioning the $28.3 million annex to the Lake Shore campus’s main library, they imagined a bookless facility that would promote group study and provide the space and technology for students to access electronic resources. They wanted this new building, which would be known as the Richard J. Klarchek Information Commons, to be sympathetic to the two art deco structures it would sit between—the Cudahy Library and the Madonna della Strada Chapel. And at the same time, they hoped it would take full advantage of its site between a campus green space and Lake Michigan. “We wanted people to realize that the lake was on the other side of the building,” says Wayne Magdziarz, Loyola’s vice president of capital planning.
Based on what you have seen and read about this project, how would you grade it? Use the stars below to indicate your assessment, five stars being the highest rating.
But university officials wanted more than a transparent structure that paid homage to its neighbors. Officials also hoped that the interior spaces—mostly open digital reading rooms—would depend primarily on sunlight for illumination. “We had clear direction from the president that natural light was absolutely essential,” says Mark Frisch, principal of technology at Solomon Cordwell Buenz (SCB), the project’s Chicago-based architects.
In order to satisfy the client’s desires for a day-lit building that would preserve the spectacular lake views and be sensitive to the existing campus architecture, SCB proposed a 70,500-square-foot, four-story glass box between a pair of limestone-clad bookends. However, this scheme, with 150-foot-long glazed facades facing east and west, presented its own set of challenges, namely controlling solar loads and glare. The exposed site and Chicago’s climate, with its cold and dry winters, and hot and humid summers, also helped make the design problem an especially tricky one.
So, to make sure the building could maintain the thermal and visual comfort of the occupants without consuming vast amounts of energy, SCB worked closely with its consultants, including Stuttgart, Germany-based environmental engineer, Transsolar, and local MEP firm, Elara. The team developed a scheme that relies on various levels of natural ventilation, combined with conventional heating, ventilation, and air-conditioning systems. The resulting “mixed mode” building, which opened in January, was designed to use less than half of the energy of one that complies with the ASHRAE 90.1-1998 standard.
The key components of the building’s exterior envelope are a double-skin curtain wall enclosing a 3-foot-wide cavity to the west, and a single-skin curtain wall facing east, toward the lake. These all-glass facades work in concert with an integrated system of radiant slabs, under-floor air, and automated operable windows. In natural ventilation mode, air enters the building off the lake through windows on the east-facing facade. It then moves across the space and through louvers on the interior face of the west wall. The natural stack effect helps exhaust the warm air through vents at the top of the double-skin curtain wall cavity.
The building can also be cooled actively. In this more conventional, closed mode of operation, the interior space is cooled with a combination of conditioned air supplied through the raised-floor displacement ventilation system and chilled water running through polyethylene tubes embedded in the vaulted precast concrete ceiling slabs. A third cooling scenario, known as “hybrid” mode, combines natural ventilation with operation of the chilled ceiling, explains Don McLauchlan, Elara principal. During winter months, perimeter fin tubes beneath the raised floor and the radiant ceiling system heat the building.
The building automation system (BAS) coordinates various elements, including the windows, the under-floor air distribution, and the radiant ceilings. To determine which mode of operation is most appropriate, the BAS tracks a number of indoor and outdoor conditions with sensors located throughout the commons and a weather station mounted on the roof. Because of concerns about condensation, two of the most closely tracked conditions are temperature and humidity. In hybrid mode, for example, “it is important to maintain the ceiling temperature a safe margin—about 5 degrees—above dew point,” says McLauchlan. If the dew point were to rise, the BAS would switch to mechanical cooling. “The ceiling is a huge mass and it changes temperature only slowly,” he explains.
The BAS also plays an important role in the building’s daylight harvesting system. It controls blinds located within the cavity of the west-facing facade, raising and lowering them and adjusting the angle of the individual louvers to control heat gain and glare. On the interior of the opposite facade, the BAS operates a perforated roller shade that blocks 92 percent of visible light when extended but still allows students to see the lake. Although a double-skin was impractical at the east elevation due to fire codes, the shade helps the single-skin curtain wall perform like a mini-cavity facade, trapping unwanted heat produced by the early morning sun, explains Devon Patterson, SCB design principal in charge of the project.
A coordinated part of the building’s daylighting strategy is the design of the electric lighting. The reading rooms have continuous rows of T5 fluorescent fixtures that provide both direct and indirect lighting. The indirect component relies on the vaults of the pre-cast concrete ceilings to reflect light into the space. (These vaults also provide more surface area than typical flat pre-cast components, helping optimize operation of the radiant system). Ceiling-mounted photocells monitor illumination levels and automatically dim the fixtures whenever daylight is abundant.
After remedying problems with the actuators that control the opening and closing of the awning windows on the east facade, the facilities management and design teams have, in recent months, begun collecting reliable operations data. So far, this limited data show higher than expected electricity consumption, due to the facility’s 300 computers, which had been set to never go into sleep status, explains Frisch. The school’s technology services department is adjusting the settings, he says.
More than compensating for the electricity consumption is the building’s better than expected thermal performance. For the month of August, the commons was in either natural ventilation or hybrid modes 37 percent of occupied hours, according to McLauchlan. Though this summer was a mild one, he says that the building is on track to operate without any fans running for about 30 percent of a typical year.
The commons is expected to earn LEED Silver certification from the U.S. Green Building Council. In addition to its unusual energy conserving strategies, other more typical sustainable features should help it qualify for this status, including materials that have a high percentage of recycled content and emit low levels of volatile organic compounds, water conserving plumbing fixtures, and a high-efficiency irrigation system. The project also incorporates a green roof that is visible from a fourth floor meeting room and helps minimize stormwater runoff into Lake Michigan.
During a visit in late June, when few classes were even in session, students could be found at the computer terminals, reading in chairs turned to face the lake, and conversing around the library tables. The high-speed Internet access, the view, or the comfy upholstered chairs might have something to do with this popularity, but Magdziarz maintains that the innovative technology is also part of the building’s appeal. “We have a very eco-aware group of students,” he says. “I have no idea where they studied before.”
share: more »