Wausau Window and Wall Systems
7250i-UW and 7250 curtainwall and 4250 thermal windows
To accomplish the design and daylighting goals, general contractor Rudolph and Sletten worked closely with glazing contractor Royal Glass and Wausau. The Helios building’s wedge-shaped design and divergent ceiling heights capitalize on Wausau’s high-performance curtainwall and windows, allowing the natural light to deeply penetrate into the interior space. In total, Royal Glass installed approximately 40 casement windows on the north elevation and 29,000 square feet of unitized, structurally glazed curtainwall on the south-facing offices, meeting space and entry lobby.
“Wausau is a true partner in every sense of the word,” says Steve Kilekas, senior project manager for Royal Glass. “Whether it’s their exceptional design capabilities, high-quality products and materials or project management support, Wausau does everything possible to ensure a flawless experience. As a project manager, that is something that has tremendous value.”
Optimized for energy efficiency, Wausau’s 7250i-UW Series unitized curtainwall features an aluminum frame with polyamide nylon structural barrier for enhanced thermal performance. The system is engineered and manufactured in ready-to-install units that vertically span from-to-floor. This approach also reduces dependence on weather seals and accommodates dynamic movements without placing undue stress on glass, sealants or other infills.
Wausau curtainwall and windows’ aluminum frames contain recycled content averaging 70% or greater. Linetec supplied the polyamide thermal barriers and three-coated painted finish. Viracon fabricated the glass.
The combination of these high-performance components and construction allow Wausau’s 4250 Series zero sightline fixed casement windows to achieve a Condensation Resistance Factor (CRF) range from 44 to 55 and NFRC U-Factors as low as 0.35. NFRC 100 “Site-Built” certification was obtained in accordance with the energy efficiency provisions required by the California Code of Regulations’ 2013 Building Energy Efficiency Standards, known as Title 24. The 2013 Standards are expected to ensure new and existing buildings use 25% less energy for lighting, heating, cooling and ventilation than the 2008 Standards. Furthermore, California’s 2013 Standards are intended to avoid 170,500 tons of greenhouse gas emissions per year.
Along with consideration for the global environment, UC Berkeley’s Helios building also emphasizes a comfortable and productive interior environment. The windows’ acoustic performance is tested for Sound Transmission Class (STC) ratings of 34 to 43. These performance factors were key for Helios’ north side, which houses specialized analytical research laboratories, laboratory support space, offices and other support functions designed by laboratory design consultant Research Facilities Design.
In addition to the thermal and acoustical performance, condensation resistance, recycled content, daylight and view offered by Wausau’s curtainwall and windows, the Helios building’s other sustainable design features include:
* automated shades programmed to activate based upon the sun’s path
* a lighting control system with sensors to turn lights off when people are absent and during off-hours
* sash closers on the 50 laboratory fume hoods with sensors that control access, reducing stress on the HVAC system
* a new air exchange system that automatically adjusts fan activity based upon occupation in the space
* individual office air system, heating and cooling controls
* low-flow faucets and fixtures
Helping connect occupants with their natural environment and community, the Helios building also offers neighbors a public park-like area to the south, a wide pedestrian pathway to the west and a commuter transit hub located on the building’s east side to shuttle visitors to and from the UC Berkeley campus.
Energy Biosciences Building; 2151 Berkeley Way, Berkeley, CA 94704; http://www.energybiosciencesinstitute.org/
* Owner: University of California; Berkeley, Calif.; http://www.berkeley.edu
* Architect: SmithGroupJJR; San Francisco. Calif.; http://www.smithgroupjjr.com
* General contractor: Rudolph and Sletten; Redwood City, Calif.; http://www.rsconstruction.com
* Glazing contractor: Royal Glass; Rancho Cordova, Calif.
* Glazing systems – manufacturer: Wausau Window and Wall Systems’ 7250i-UW and 7250 curtainwall and 4250 thermal windows; Wausau, Wis.; http://www.wausauwindow.com
* Glazing systems – glass fabricator: Viracon, Inc., Owatonna, Minn.; http://www.viracon.com/
* Glazing systems – finisher: Linetec, Wausau, Wis.; http://www.linetec.com/
* Photos by: Bruce Damonte Photography