After the Doge’s Palace, the largest building on the Grand Canal near Rialto is the former Fondaco (or Fontego) dei Tedeschi. Functioning since 1228, it served as the warehouse for all commercial goods coming from Northern Europe and as a guest house for both merchants and prominent guests from the German countries (for instance, Dürer). There were two dining halls (one for the summer and one for the winter), several meeting rooms, and all what was needed for a self-sufficient foreign colony. In brief, the building housed a monastery, a commercial community and a real village at the same time. Rebuilt in 1505 after a fire at the Serenissima’s expense, the edifice stood in the neighbourhood of the most important trading hub of the city and was functionally integrated with the commercial distribution by means of a number of shops lined along two streets on the ground floor. On the other hand, the building inevitably maintained a privileged relationship with the traffic on the Grand Canal, as one can easily infer by the partition of the front in three sections, the central one being characterized by a tall and deep five-arch porch on the ground floor, opening onto the water to welcome people and goods. Once, this fa.ade used to bear frescoes executed by Giorgione, while another fa.ade along one of the streets was decorated with frescoes by Titian, but both cycles are now missing. The walls of the inner courtyard used to be interspersed with a row of arches progressively reduced in height, which opened onto arcades and loggias, whose masonry mass they helped lighten. The most significant changes were made during restoration works between 1928 and 1939, aimed at adapting the building to its new destination as central post office. The structures were consolidated with the introduction of reinforced concrete elements into masonry for load bearing purposes; the floors were replaced or reinforced; the roof was totally replaced with a new reinforced concrete truss covering.
Thanks to the restoration and functional rehabilitation designed by OMA architects, the Fondaco dei Tedeschi – today the property of Benetton group – has become a commercial area and houses the shops of the luxury brand LVMH, as well as some other areas open to the public.
The restoration works were entrusted to Rizzani de Eccher and Sacaim. They included several interventions, among which the restoration and raising of the original roof to accommodate a new multi-purpose area and the execution of a global protective system against the “high tide” – a recurrent seasonal event in Venice – are certainly worth mentioning.
OMA’s design included the elevation of the 19th century steel and glass roof to make room for a new volume to be used for public events. The original roof was lifted by 1,6m and propped up with new steel pillars, which are longer but as wide as the original ones. Another row of pillars was added to guarantee greater stability against seismic vibrations.
The 19th century roof was disassembled and brought to the restoration workshop to check its profiles, nails, tie rods and all anchorages. Any weak elements or connections were replaced or reinforced, with a view to adapting the whole structure to the current standards. Period glass elements were replaced with new glass to guarantee ultimate comfort inside the multi-purpose area. This new “glazed room” was suspended on top of the central courtyard with the help of a 60cm high steel beam network (HSA 538/168). Access to the area is ensured by lifts and an escalator, which reach a gallery with a new flat top running from the ridge line of the original roof to the central pavilion, obtained after the demolition of the under pitch.
The building was “defended” against the action of exceptional tides as high as +2,00 above sea level as compared to the zero reference point of Punta della Dogana. The protective system consists in a basin with a specially conceived concrete conglomerate bottomand – wherever required – side walls. This special conglomerate features high mechanical resistance and controlled shrinkage; moreover, silica fumes were added to the mix so as to obtain a more compact matrix as compared to traditional concrete.
The courtyard columns have been lifted and the waterproof basin has been stretched below their stands.
The new reinforced concrete elements, including the cable tunnels, lift and elevator shafts, have been executed with the same technology and the same materials; they have been connected to the structure of the basin and all joints have been waterproofed with “seams” and hydrophilic resins. On the other hand, any extant reinforced concrete structures, as well as spine walls and load-bearing walls in general, have been finished with fibre-reinforced non-shrink waterproof plaster. All in all, these interventions helped obtain two results at a time, that is the whole foundation system was waterproofed and consolidated. [text E. Martino]
[by Marzio Mazzetto, Lucia Veronica Ciuffi – SACAIM]