Case studies

Chigi’s Palace, Piazza del Campo, Siena, Italy

05_Siena_VimarkThe Piazza del Campo in Siena is certainly one of the most iconic and celebrated medieval squares in Italy.

Known throughout the world for its peculiar concave shape, similar to a shell and divided into nine sectors by strips of light coloured stone and herringbone laid bricks, it is located in the ancient Roman forum in the city centre. Erected all around is a crown of 14th century buildings of Sansedoni, Piccolomini, Tolomei, Saracini, Buonsignori, Palazzo of Merchandise and Chigi that circumscribe the area. Years ago, the entire city’s population would gather in the Piazza del Campo that would transform, depending on the occasion, into a place of entertainment with medieval games and festivities.

The renovation company Bernini Emilio and Luca carried out in 2002, a preserving restoration and renovation of the facades of the Palazzo Chigi. The intervention brought back to its former glory the only building finished with rendering mortar in the entire square. The main purpose of the operation was to restore harmony and light to the elegant and antique façade of the building overlooking the arena of the most famous Italian street horse race known as the Palio. The restoration project sought to preserve the historic features that make the site an integral part of the most complex and fascinating medieval city centre.
After a survey and analyse of the facades and the existing materials, some portions of the ornamental plasterwork were found to be damaged and in some cases even missing.

The first step in the preserving restoration and renovation of the external walls on three sides and those of the inner courtyard of the building Palazzo Chigi in Siena, was the removal of existing plaster down to the brickwork. The bricks were laid with lime and hydraulic based mortar and local river sand.

After a thorough cleaning of the surface, a layer of mortar was applied mechanically with the product Calcinto and subsequently a finishing layer with the tonachino Calcina Civile based on natural hydraulic lime. The final aesthetic effect was obtained with the help of sponge trowels and brushes for the pilasters, cornices and architectural friezes.

The pictorial integration of the decorative film was obtained by brush application of coloured silicate products that maintain coefficient the vapour permeability set by the plaster.

Intervention data sheet

Building: Palazzo Chigi, Piazza del Campo, Siena Italy.
Type of intervention: Preserving restoration of the façade.
Contractor: Bernini Emilio e Luca.
Plasterer: Civas s.r.l.
Project manager: Arch. Isidori Marco; Geom. Corbelli Mario.