Photo © Deep Blue Studio Photo © Deep Blue Studio
The arcades of Piazza Ducale in Vigevano : a new light designed on a human scale
C onsidered one of the most beautiful squares in Italy , Piazza Ducale , which has always been a place for social gathering in Vigevano , needs no introduction . The surrounding arcades , made to human scale , give a particular sense of intimacy and protection . The low cross vaults and the tight rhythm of the colonnade almost give the impression of being in the peacefulness of a cloister , rather than in the noise of a square . In such cases , working on lighting means giving up on spectacle and monumentality and making an exercise in proportion , seeking minimum impact and maximum comfort , while fully respecting the genius loci . It is in this spirit that the work on the lighting of the Piazza Ducale was part of the energy requalification project carried out by Citelum in Vigevano and completed in 2019 , which has reduced the energy needs of the street lighting service by 69 %. The morphological richness of the urban context has required care and continuity in tackling the issues of lighting streets and monuments , also in relation to the existing systems : the porticoes were lit by simple lamp holders installed just above the capitals and summarily shielded by a bulky opaque and open diffuser . The design challenge , which began as an experiment and was developed in response to the appreciation of the Superintendence , was to avoid replacing the luminaires but rather to “ make them disappear ”, i . e . to reduce their visual impact to zero as far as possible . Thin LED bars have been superimposed on each individual tie-rod to provide a fully indirect lighting . The light sources were made completely
Gli arredi storicizzati al centro della piazza sono stati oggetto di un retrofit dedicato per non mutarne l ’ aspetto , mentre le facciate esterne non sono state illuminate , preservando lo storico effetto positivo / negativo dei porticati / The historic furnishings in the square ' s centre have been retrofitted so as not to change their appearance , while the external facades are not lit , preserving the historic positive / negative effect of the arcades
invisible by the millimetric fine-tuning of the special containment profile to the linear diffuser of the bars . Right from the very first tests , the system provided excellent uniformity , with the rhythmic chiaroscuro ensured by the very morphology of the cross vaults . The outcomes are a practically non-existent visual impact during the day , a discreet and comfortable night-time effect , and a substantial improvement in the evenness and levels of illuminance and luminance , both on the vaults and on the floor . While the selection of the lighting engine made it possible to find an easily customisable and optimally sized solution – the light bars –, the search for drivers small enough , but with electromechanical characteristics suitable for an outdoor installation , was much more laborious , although equally successful . The development of this solution , later applied to all 78 tie-rods of the square , required several field tests to define the optimal colour temperature – 2,700K – and which geometric factors , photometries and luminous fluxes were necessary to achieve the desired effect . The work was then completed by the cleaning of the vaults and the removal of obsolete elements of the old system , as well as by some minor painting works . As confirmed by the mayor Andrea Ceffa , the long-awaited redevelopment , which was completed at the beginning of 2021 , “ has made it possible to further enhance the uniqueness and beauty of our Piazza Ducale and of its arches in particular , certainly constituting an element of overall enhancement of our city ’ s heritage .”
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