The problem of conservation of XX century architectural heritage: The fibreglass dome of the Woodpecker dance club in Milano Marittima (Italy)

The present study deals with the deterioration of materials in the dome of the “Woodpecker” dance club designed by the architect Filippo Monti (1928–2015) and built in Milano Marittima (near Ravenna, Italy) in 1968. This place, considered extremely valuable due to its landscape and architectural features, has been in a state of abandonment for around 40 years, but recently the local Municipality has started a process for its restoration. The dome is made of 23 fibreglass precast rib vaults hiding a steel structure, and in early 2000s a large part of its internal surface was painted with a graffito by Blu, an internationally renowned Italian street artist. Nowadays, both the dome and the graffito are safeguarded for their historic-architectural-artistic value by putting restrictions to their demolishment and modification. However, both the dome and the graffito are affected by harsh kinds of degradation, very different from those affecting historical building materials, which endanger their state of preservation. This study investigates whether the methodological approach of the conservative restoration can be applied to this structure, which is an example of contemporary architecture. Because of the lack of project drawings, a visual investigation was carried out to define geometric features and the most important technical details, and to deduce plausible hypotheses about building techniques that were adopted. The degradation affecting the dome and the graffito was then investigated, and samples of fibreglass, steel and paint were collected. Laboratory analyses on these samples, in addition to environmental studies concerning wind, ground water and relative humidity, were conducted to characterize the materials and identify their main deterioration processes. A possible restoration solution in accordance with conservative restoration principles was finally proposed, showing that the application of the same methodological approach used for ancient buildings arises many challenges, due to some key peculiarities of XX century architectural heritage materials