A Mid-century Glass and Steel Structure Receives New Glazing Systems

Honorable Mention, Wild Card

Gund Hall on Harvard University’s campus in Cambridge, Mass., is a bold example of late modern concrete architecture. Architect John Andrews believed the glass and steel enclosure over the stepped studio trays was the 1972 building’s most important design feature. His approach to using glass stood apart from earlier Brutalist buildings in Cambridge and Boston—like Boston City Hall and Le Corbusier’s Carpenter Center—which tended to hide or recess glass elements. In contrast, Gund Hall’s curtainwalls are large, visible glass volumes that help define the building’s overall shape, working in harmony with the concrete structure and 120-foot-long steel trusses that span the studio roof without columns in between. 

PHOTOS: Chuck Choi; BEFORE/HISTORIC PHOTOS: Bruner/Cott Architects; DIAGRAM: Bruner/Cott Architects; PLAN: John Andrews

During the past 50 years, the building has experienced leaks, failing window assemblies, and interior discomfort caused by heat loss in winter and overheating in summer. When Gund Hall was first designed, it wasn’t used during the summer months. Since then, student use has more than doubled, and the building is used year-round. These issues, combined with growing concerns about energy use and carbon emissions, made the need for upgrades urgent. 

The 2024-25 project comprised the first phase of a comprehensive, carbon-conscious conservation effort focused on replacement of the vast studio’s glazed enclosure. The design and engineering for replacement of multiple glazing assemblies respects the visual framework set by Andrews’ original elevations—externally and as viewed from within. Cambridge Historical Commission staff visited the project during early mock-up phases to help the design team compare new elements to their original counterparts side-by-side. 

The studio’s three elevations involve multiple, differing specifications for glazing and newly engineered bespoke glazing systems to deliver the design intent of the original neoprene and aluminum façade components. The variety of specifications corresponds to differences in solar exposure for heat gain, natural light transmittance, glare reduction and the appearance of Andrews’ original single-pane solutions. Constructability over a single collegiate summer was a critical challenge. There are 112 clerestory windows at the stepped roofs visible from Cambridge Street. Each window replacement involved six different trades! 

The new envelope uses hybrid vacuum insulated glazing as curtainwall on gridded north and south elevations. The assembly delivers thermal performance that is four times better than a double-glazed insulated glazing unit of the same dimension. The stepped east façade uses triple-pane glazing where thickness is less visually critical. 

Gund Hall’s envelope replacement is respectful of Andrews’ design and the environment. The project expended approximately 160,000 kilograms of CO2 to produce but is modeled to save 18,000 kg of CO2 per year with a projected nine-year carbon payback. It exemplifies a new paradigm in architectural preservation where technical innovation and design integrity come together to extend the life of Mid-century Brutalist buildings in a carbon-conscious future.

Judge’s Comment

Retrofit Team

Design and Executive Architect: Bruner/Cott Architects

Construction Manager: Shawmut Design & Construction

Structural Engineer: Simpson Gumpertz & Heger

MEP Engineer: Vanderweil Engineers

Daylighting Consultant: Lam Partners

Building Enclosure Commissioning: Heintges

Glazier: A&A Window Products

Materials

Vacuum Insulated Glass, Glass Substrate and Glass Coating: Vitro Architectural Glass 

Curtainwalls and Insulating Glass Units: Oldcastle BuildingEnvelope

Built-up Roofing: Johns Manville

Cold, Fluid-applied Membrane: Kemper System 

Hardware: Allegion 

Sliding Doors: NanaWall

Paints and Stains: Tnemec and Sherwin-Williams 

Shades: Lutron