Kathleen Grimm School for Leadership and Sustainability
Designers faced multiple challenges in creating a plan for the Kathleen Grimm School for Leadership and Sustainability (P.S. 62) in Richmond, New York. The goal was to produce the city’s first net-zero energy school and one of the first of its kind in the world. To help achieve this goal, designers used architectural precast concrete panels with projecting “ribs” interrupted with brightly colored window frames that add a whimsical touch.
Designed to comply with the SCA Green Schools Guide in lieu of LEED certification, the 68,000-square-foot, two-story school serves 444 pre-K through fifth-grade students. The school serves as the NYC School Construction Authority’s first “sustainability lab,” featuring a variety of energy-efficient designs tried for the first time on this project.
One of these sustainable and low-energy features was an ultra-tight, high-performance building envelope featuring architectural precast panels that serve as a rain-screen system. The panels channel rain into underground tanks that collect the rainwater. BPDL Béton Préfabriqué cast the precast concrete components for the project.
The panels were cast in 30-foot lengths and were erected vertically to span from the foundation to the roof without any intermediate connection to the structure, explains Christine Bouchard, organizational development manager at BPDL. “The goal was to provide the tightest seal possible.” The 30-foot length ensured no penetrations were necessary through the building’s insulation and vapor barrier, providing as airtight of a building enclosure as possible.
The architects chose various shapes and volumes for the precast concrete panels to create unique “rib” elements that add a dimensional aspect to the panels. The large punched windows, which are slightly misaligned, feature wide, asymmetrical frames painted in varying bright colors. “The irregularly undulating pattern was meant to break up the building’s mass,” she explains.
Although the panels are tall, the pleats help give them a scale and texture that appeal to children as well as adults, according to a spokesman for SOM, the project’s architect. The windows feature triple-glazed panes to boost energy efficiency.
The project required 162 precast panels with an average weight of 18,000 pounds and an average surface area of 34,500 square feet. The precaster used one mix design for the concrete, mixing gray and white cement, with a heavy sandblast to reveal the aggregates and achieve a natural stone look.
As the design required elliptical shapes, special mold elements were inserted into the forms to achieve the pleated appearance. Those elements had to be designed in such a way that they could be easily adapted from one mold to another while keeping it interesting and economical, Bouchard says. A member of the inspection team or a representative of the precaster was on-site each day during the erection to ensure the panels were erected smoothly and properly.
Architectural Precast Elements:
• Net-zero energy use.
• 30-foot tall panels with no penetrations.
• Vertical projections create dimensional “pleats” in the panels to reduce the building’s visual mass.
• Combination of gray and white cement in concrete mix.
• Heavy sandblasting.