Control centre, Venice

MOSE (an acronym for MOdulo Sperimentale Elettromeccanico, in English, Experimental Electromechanical Module, as well as an allusion to the name of the prophet Moses and the miracle of the parting of the waters during the Flight from Egypt) is a system of underwater mobile gates in the Venetian Lagoon designed to control tidal waters. Once the project becomes operational (the forecast date is 2014, though forecasts in Italy are not always to be relied on) it will keep the waters of the Lagoon from rising above 110 centimetres, a level that causes problems for residents and tourists alike, as well as flooding the ground floors of the city's buildings.

In line with their architectural research, which focuses on a refined and sensual approach, though pared down almost to the point of minimalism, Cappai and Segantini proposed an historically exemplary renovation and, at the same time, the insertion of a non-aggressive though non-mimetic element with a modern form.

The objective was to propose a minimally invasive technology, a contemporary layer that is discreetly added to the sedimentations typical of the building's history. 'We played,' Segantini tells us, 'with the memory of the space. An empty space, originally occupied temporarily by ships under construction or being refurbished.'

This was achieved by carving out a basement level to contain the most cumbersome equipment, demolishing an infelicitous later addition and substituting it with a veranda lit from above, and, finally, by inserting a Cor-Ten steel service box inside the shed. This volume, which functions as an umbilical cord between the lower level and the roof, contains all of the piping and other technical elements best hidden from view. To avoid it looking like a banal service shaft, it was transformed into a sculptural and highly plastic object, reminiscent of the works of Donald Judd or Richard Serra.

Lightweight wood and glass walls subdivide the space containing the offices and meeting rooms, maintaining the unified perception of the original shed. The parquet flooring was raised to accommodate cabling and ensure the flexibility of the workstation outlets. Thanks to the continuous wood flooring, the end result is very different from the fragmentary appearance typical of raised access flooring systems composed of prefabricated square tiles.

The restoration of the teza also revealed the quality of the structure of its materials: in particular, the bricks highlighted by a thin layer of plaster that vibrates under the light. The roof was disassembled and restored, maintaining the original materials where possible. However, the most successful part of the project is without a doubt the new roof of the veranda that, as mentioned, replaced a previous addition. Photovoltaic cells set into the glass roof structure produce energy and shade the office spaces, producing a highly contemporary pattern of light and shadow.

The project also includes other energy-saving measures, including a geothermal system that draws heat from the ground. While in Italy these technologies are now widespread in new constructions, they remain very rare in restorations and projects involving listed buildings. Segantini: 'This project at the Arsenal was one of the first renovation projects to systematically apply the principles of sustainability.'

Beyond its technological merits, the building represents an optimum example of the possibilities offered by interventions even in such a delicate location as the city of Venice: rehabilitating the material qualities while simultaneously enriching them by applying seductive and non-aggressive technologies, an approach that is not so much high-tech as soft-tech, or even high-touch. The new is superimposed on and integrated with the existing, but does not take its place: it is a poetic that privileges the and/and instead of the or/or. 'It is a new layer,' Segantini concludes, perhaps with a hint of rhetoric, 'that seeks to confront the chiaroscuro nature of Venetian memory.'