High Concrete Group LLC has introduced ThinCastTM, the thinnest precast concrete rainscreen panel available on the market. Designed for use in commercial, institutional, retail, and low- to high-rise construction, this innovation provides architects with the natural beauty and character of concrete in lightweight panels that accomplish their rainscreen design goals.
Location: Springfield, Ill.
Type of Precast: Architectural Cladding
Size: 135,000 sq. ft. (24,000 sq. ft. of precast cladding)
High tech AIG branch offices clad in elegant precast
This $25 million project was built-to-suit world insurance leader AIG American International Group.The company’s new Springfield Service Center is situated on the west side of Springfield, Ill. AIG relocated there in March 2008 from a 375,000 square foot downtown facility that was purchased by the state.
Designed by Opus Architects and Engineers, and developed and built by Opus North Corporation, the 115,000 square foot Class A office building comprises three stories of nearly 40,000 gross square foot floorplates. The steel frame building is clad in architectural precast in earthtone colors with gray tinted insulated glass and aluminum window system.
Precast is the right look
The exterior colors were carefully considered for the project, and were selected to be warm but not dark. A quiet, clean expression, the outside walls combine two finishes that achieve two distinct colors in the 8”-thick precast panels while using a single concrete mix. Exposed aggregate creates a bold texture that is contrasted by a medium sandblast. A banded reveal at the columns provides scale in the stone-like visual.
Exposed aggregate finishes are accomplished when a retarder paste is applied to the surface of the form. The past prevents the concrete matrix from curing in the first few mils of the face surface. When the panel is removed from the form, a water jet washes away the paste and the uncured matrix, leaving the shape and color of the aggregate fully exposed. The effect draws attention to the stone and creates a textured surface with its own color, and allows the panel to perform as designed.
State-of-the-art building becomes a model for AIG
Precast cladding is a standard at Opus, which believes it provides a higher level of quality than masonry in its durability, detailing and visual interest. Precast also helped accelerate the project schedule, which went from ground breaking to completion in 10 months.
Extra care was taken with the entrance, which is positioned in a set back enhanced with parapet and accent panels. The designers played with the materials, adding light-colored metal panels in the surrounding glass area to complement the precast. The result is a high-quality, non-flashy image that nevertheless draws the eye.
Windows were mounted half on the panel and half on the interior framing, a construction practice that covers the joint. The office envelope allows lots of light into the interior, and views for the approximately 460 customer service, information technology, underwriting and new business workers.
AIG emphasized the high-tech nature of the new building, which is hard-wired for video conferencing and other high-tech services to AIG centers in
Houston , Milwaukee and Dallas . The high-tech theme is carried throughout the structure — “huddle” rooms in addition to the traditional conference room, video-screens strategically located on each floor and “collaboration” areas. It was one of the first downstate projects for designer Opus North Corporation ofChicago .
There also are special touches such as a “mother’s room” for nursing mothers, as now required by Illinois state law, break rooms on each floor and a catered cafeteria. AIG cites the new building as a model for greater productivity and profits for one of the world’s largest financial services corporations.
The interior lobby space features building reception and security. The reception lobby and elevator lobby have stone floors with natural and painted wood walls. The first floor contains cafeteria, training and conferencing areas. The office layout places workstations and offices near the windows with support function such as restrooms, service centers, and break areas in the core of the building.