The exteriors present a widespread deposit phenomenon which affects all the surfaces, be they stony, plaster or metal.

In the stony elements the presence of black crust is evident, in particular on the main façade, due to the naval pollution on the Grand Canal, and above all in the elements located in a position protected from the run-off of rainwater, such as in the niches, in the arches and in the interstices. Pouring phenomena caused by the runoff of rainwater are instead present in all those parts that are subject to the geodesic action of rainwater in the Corinthian capitals, under the jambs of the windows.

The presence of upper vegetation is evident in some points of the lateral facades, especially in the bossage base. Moreover, there is a biological patina made up of biodeteriogenic agents, which took root on the most bio-receptive surfaces which are less exposed to the sunlight.

There are cracks and fractures on some stony panels and other elements that are subjected to tension. Some fractures were previously treated with metal elements that caused spots on some stony elements due to their oxidation.

The action of the wind is evident on all the stony elements that characterizes almost all the external façade of the church, in the form of erosion. There are rises and separations also near the existing cracks. We can notice lots of stony elements with chips and missing parts, especially in correspondence with the corners or the most projecting parts. It is a localized and common phenomenon. The most compromised elements are subjected to the flaking phenomenon, especially on those at high altitudes, due to the atmospheric agents to which they are exposed.

In the external plasters the current state is partially compromised. In addition to the widespread superficial deposit, the deposit is usually subject to erosion, with swelling and separations that in some areas have led to the fall of the plaster itself, highlighting the underlying brick masonry or the background plaster layer in cocciopesto. The runoff of water in some areas also caused vertical pouring that marked the plaster on the side facades.

There are biological patinas with different colors depending on the solar radiation to which the plaster is exposed. The saline efflorescences are also evident. They can be seen in the form of "white beards" in the dampest and less ventilated parts

In addition to the widespread superficial deposit, the degradation caused by their oxidation is recognizable in the metal elements, a natural phenomenon that leads to the formation of rust with consequent corrosion of the metal. This phenomenon also involves the surrounding elements due to the fact that the rust can be carried and deposited on other materials causing patches.

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The restoration work