Form to Facade: Italy’s First Nearly Net Zero Building: Gioia 22, Milan
Session: Track D: Façade Engineering Award, Life Safety Design Award, Part 2 & Innovation Award, Part 2
Fund & Asset Management Director, COIMA
Associate Principal, Pelli Clarke & Partners
The site for Gioia 22 is in Porta Nuova, Milan’s recently-developed business district. At its base, the tower is aligned to the axis of Melchiorre Gioia, a major north-south thoroughfare. As the tower ascends, its south portion begins to skew to the east, realigning with the skewed eastern city grid. The curtain wall rises above the top story to create a highly contemporary addition to the city skyline that is especially striking for Milan, a mostly low-rise city.
The façade design was driven by a solar control strategy and particularly focused on energy performance. A high-performing façade wraps up the tower. Triple-glazed units are combined with insulated, thermally broken aluminum frames to provide an overall transmittance level that complies with astringent thermal requirements. An ad-hoc unitized system façade design mitigates the heat loss and the thermal bridges, significantly contributing to the building’s energy saving strategy and meeting Nearly-Zero Energy-Consumption Building targets. Highly selective glass coatings and sunshades control the solar radiation and optimize the users’ visual comfort. Where sunshades are not present, low-E coatings have been included in the glazing units to provide insulation and avoid overheating of the internal environment.
A sun-reflection parametric analysis was carried out to detect potential concentration of sun rays on specific façade portions, which is especially important due to sloped and twisted surfaces. To reach the energy performance target, building-integrated photovoltaic (BIPV) modules were integrated on the building rooftops, as well as into the tower skin. In total, there are about 2,300 photovoltaic elements integrated in the façade, generating 38 percent of the building’s renewable energy requirement, covering a surface area of 5,200 square meters.