Daylighting D.C.: Office building in prominent D.C. area implements daylighting for efficiency
by Jonathan McGaha | January 31, 2010 12:00 am
The 260,000-square-foot (24,154-m2) LEED Gold certified 901 K Street office building in Washington, D.C., fills a unique, triangular-shaped space in D.C.’s office landscape, both in design and location. The 12-story, $60 million project was developed by Washington, D.C.-based Carr Properties & Affiliates and designed by SmithGroup, Washington, D.C. The project’s daylighting and energy efficiency objectives were met with the help of sunshades and a curtainwall system from Wausau, Wis.-based Wausau Window and Wall Systems.
According to John G. Crump, AIA, LEED AP, principal at SmithGroup, the goal was to design a sleek, sculptural building that was appropriate to the prominent setting at one of the major vehicular gateways to the city, while breaking down the form of a typical office building block into smaller pieces that build from the smaller scale façades along the park to soaring façades along Washington’s famous K Street commercial district.
The new construction project began in May 2007, and in Fall 2009, less than a year after the building’s curtainwall installation began, occupants began moving in.
“In a tough economy, property owners are doing all they can to attract and retain occupants. In a world of diminishing natural resources and global climate change, building owners also are constructing and managing their properties with environmentally friendly practices,” said Kevin Robbins, Wausau’s regional sales manager.
Carr Properties developed the prominent office and retail space in a desirable location with 11,400 square feet (1,059 m2) of green roofs to minimize the urban heat island effect, water-conserving plumbing fixtures, low-emitting interior materials and low-VOC finishes. Additionally, the building’s energy-efficient lighting system and high-performance, non-CFC HVAC system are complemented by Wausau’s curtainwall system and sunshades. The floor-to-ceiling windows allow 60 percent of the building’s interior space to receive natural light.
Due to the building’s location-on a triangular site in the heart of Washington overlooking Mount Vernon Square-the project also needed to address security with consideration of the neighboring government and landmark buildings, including the Mount Vernon Place United Methodist Church, the Henley Park Hotel and the Carnegie Library, in addition to the surrounding community.
The building’s south side faces K Street, affording occupants expansive views of the historic neighborhood and downtown Washington. With respect to the nearby community, the northeast elevation on Massachusetts Avenue was designed with a softer façade of terracotta paneling and ornamental accents.
“We designed a curved terracotta rainscreen façade facing Massachusetts Avenue that relates to the context of the adjacent smaller scale masonry buildings,” said Christopher Woody, project architect with SmithGroup. “This represents one of the first uses of this type of cladding system in the District of Columbia.”
Woody continued: “One of the major project challenges was coordinating the design and installation of the terracotta and the curtainwall façade. Wausau’s team collaborated with us from the beginning to reach a successful solution that integrated the façade’s diverse materials. The system we chose fit well within the design intent while keeping within the budget.”
We wanted to create opportunities of unprecedented interior views of the city through expanses of floor-to-ceiling glass, according to Crump. “The curtainwall systems were designed to distinguish the various massing elements of the building, and improve the natural daylighting and energy efficiency of the overall project.”
By using standard glazing components combined with the new terracotta technology, the building’s design is able to express several unique facades that address the commercial, cultural and ecclesiastic surrounding buildings, Crump said.
The exposed aluminum framing was painted by Wausau-based Linetec to match the terracotta and blend together the building’s style and systems. According to Wausau Project Manager Carl Wanta, aside from the terracotta rainscreen, the three-side support, glass sunshades were a first for Wausau. “These are both decorative and functional, helping contribute to the building’s solar control for energy management and related LEED requirements.”
Wausau provided approximately 6,700 square feet (622 m2) of its RX Series window wall and approximately 60,700 square feet (5,639 m2) of its UW Unit Wall Series curtainwall, in addition to approximately 2,400 square feet (223 m2) of custom sunshades and ornamental accents for the project. Owatonna, Minn.-based Viracon supplied its VRE-38 glass, while Linetec used a two-coat, 70 percent PVDF Mica Sunstorm paint.
“Given the amount of glass on the building, we were able to use Viracon’s high-performance, radiant low-E line of VRE glass, which helped us achieve the heating and cooling loads we needed for the building,” Woody said.
According to Crump, the project utilized a relatively new line of glazing products from Viracon that provide a low Solar Heat Gain Coefficient while maintaining a high visible light transmittance. “The high-performance, VRE line of glazing has radiant low-E coatings which improve the energy performance of the building by decreasing the solar heat gain thru the glazing while allowing increased levels of natural light to fill the office space.”
“Large southern exposures require thoughtful planning to maximize daylighting and views, while managing energy costs,” explained Wanta.
“Effectively-engineered, modern curtainwall systems not only keep energy costs down by managing unwanted solar heat gain, which reduces the load on the HVAC systems, they keep people more comfortable, which means they’re more productive in an office setting.”
“Meeting LEED building criteria does not mean compromising on materials and finishes. Green does not have to mean dull and utilitarian,” said Mark Gedney, Wausau’s manufacturer’s representative and president of Advanced Building Concepts Inc., Lutherville, Md. As evidence, Gedney pointed out the terracotta rainscreen, the custom glass sun shades from Wausau, and the dramatic, east lobby’s five-story atrium containing Ambarino marble, Peribonka granite and maple paneling.
Due to Wausau’s high-performance systems and the glass from Viracon, the lobby’s finishes are protected from fading, while allowing the occupants to enjoy a comfortable interior climate. The transparency of the building’s curtainwall system keeps guests connected with the surrounding environment. In addition, the building also physically connects to the neighboring Mount Vernon Place United Methodist Church, a 1917 neoclassical church that plays a prominent part in the historic neighborhood.
901 K Street, Washington, D.C.
Owner and Developer: Carr Properties & Affiliates, Washington, D.C.
Architect: SmithGroup, Washington, D.C.
General contractor: Clark Construction Group, Washington, D.C.
MEP engineer: Girard Engineering PC, Falls Church, Va.
Structural engineer: Smislova, Kehnemui & Associates PA, Rockville, Md.
Civil engineer: Wiles Mensch Corp., Washington, D.C.
Manufacturers representative: Advanced Building Concepts Inc., Lutherville, Md.
Glazing contractor: Icon Exterior Building Systems, Washington, D.C.
Glazing system: Wausau Window and Wall Systems, Wausau, Wis., www.wausauwindow.com
Glass: Viracon, Owatonna, Minn., www.viracon.com
Finisher: Linetec, Wausau, www.linetec.com
Source URL: https://www.metalarchitecture.com/projects/daylighting-dc-office-building-in-prominent-dc-area-implements-daylighting-for-efficiency/