The first phase of an extensive rehab at Gund Hall by Bruner/Cott, reported on by AN last December, is now over at Harvard GSD. The job entailed negotiating an iconic 1972 Brutalist building by John Andrews and making it perform better. The Boston office reskinned Gund Hall with a new high-performance envelope, helping it cut down energy costs and improve usability while providing other ancillary benefits. By the numbers, 1,617 glazing units were swapped out with new ones. Gund Halls east curtain wall and clerestory windows now have triple-pane glass, and the north and south curtain walls are stocked with hybrid vacuum-insulated glass. Motorized window shades now mitigate heat gain from direct and reflected sunlight; this gadgetry reduces glare for students toiling in the trays and the pit.Gund Halls east curtain wall and clerestory windows now have triple-pane glass, and the north and south curtain walls are stocked with hybrid vacuum-insulated glass. (Chuck Choi)Exits to the terrace were also widened to make Gund Halls outdoor spaces accessible to those with reduced mobility, marking the first time in the GSDs history where those egress points have been wheelchair accessible. Outside, concrete that was deteriorating was patched up by construction crews. Bruner/Cotts design team, which include George Gard and Jason Jewhurst, made the conscious decision to keep Gund Halls 50-year-old facade support steel within the buildings original glazing system. For Sarah Whiting, Harvard GSD dean, the renovation is cause for celebration. In a statement, Whiting said for the first time in over 50 years, the trays will be warm in the winter, cool in the summer, and we wont have rain leaking onto our desks.When John Andrews was originally tasked to design a new facility for the Departments of Architecture, Landscape Architecture, and Urban Planning and Design, he surprised his clients with a unique building that was at once solid and transparent and prioritized the student body, united within an enormous, light-filled, single space, Whiting continued. Though much has changed since Gund Hall first opened in 1972, the careful rehabilitation of the structure underscores the schools commitment to this same priority: our students.Navigating An Enormous, Light-Filled, Single SpaceHow did Bruner/Cott, engineers, and consultants make Gund Hall more energy efficient and less leaky? The new envelope adds another layer of conventional insulating glass, creating a sandwich thats just a few millimeters thicker than your average double glazing.This extra few millimeters may seem small, but it pays dividends: Triple-pane glass is almost ten times more efficient than single-pane glass, Bruner/Cott said. This technology, architects added, is already popular in Europe. Gund Hall is now one of the first buildings in the U.S. to employ it on a large scale.An exterior detail shows the improved glazing. (Noritaka Minami)The windows meet advanced energy codes. (Noritaka Minami)At Gund Hall, the new special window assembly system meets advanced energy codes while conserving original design elements. Designers at Bruner/Cott used BIM software for slashing carbon emissions and energy consumption, making the building more storm resistant. The natural light is also now much better inside the trays, Bruner/Cott noted. The renovation exceeded Massachusettss stretch energy code for alterations. According to calculations, the renovation will save about 18,000 kilograms of CO2 emissions per year, meaning a nine-year carbon payback as a result of the project. Gund Hall will also realize 22.2 percent reduced energy use intensity and a 19.1 percent reduction in utility costs.David Fixler, a GSD lecturer who chairs the departments Building Committee, said that the idea to upgrade the trays glazing had been in and out of the GSDs eye for the better part of two decades, and this latest renovation makes Gund Hall a more environmentally friendly place.Project SpecificationsDesign and Executive Architect (Prime Consultant): Bruner/Cott ArchitectsBuilding Envelope Consultant, Structural Engineer: SGHOwners Project Manager: RedgateDaylighting Consultant: LAM PartnersSustainability, Electrical Engineer, Mechanical Engineer: Vanderweil EngineersSpecifications: KalinBuilding and Accessibility Code: Jensen HughesBuilding Envelope Consultants: HeintgesConstruction Manager: Shawmut Design and ConstructionGlazier (Key Sub-Contractor): A&A Window ProductsCurtain Wall and IGU Fabricator (Key Supplier): Oldcastle BuildingEnvelope (OBE 360)Vacuum-Insulated Glass, Glass Substrate, and Glass Coating Supplier (Key Supplier): Vitro