The oldest areas of the church were also the most degraded ones. Before the start of the 2013-2015 restoration, the majority of walls and all the vaults had several fissures, cracks and fractures.
After assembling the scaffolds inside the central choir, all the surfaces with historical plaster and mural paintings were researched and revealed. The church walls were quite degraded with cracks and fissures in the areas with historical plaster and mural paintings, so that the structural reinforcement of these areas was extremely complicated. After the consolidation of foundations, the intervention on the superstructure began. With supervision from the mural painting restorer, the plaster was removed in the fractured areas then the cracks were re-bonded in a stone-by-stone manner, in order to insure the continuity of the masonry. Fissures and cracks of moderate size were only wedged and injected with lime based hydraulic plaster. Similar works were carried out in the lateral choirs and in the former sacristy, where the masonry of the North-West corner had partially collapsed owing to the maceration of building material, at a height of 1,5 m and it was rebuilt.
After removing the refuse layers on the extrados of the vault over the central choir, and after having removed the plaster in the area of intrados fissures and cracks, a worse state of degradation of the vaults was revealed than initially estimated (before assembling scaffolds and revealing surfaces). The arches are self-bearing decorative ribs, they have no connections in the depth of the vault’s masonry. The real width of the vault was identified as one-brick, 28 cm, and not half-brick, 14-15 cm, wide. The bricks in the vaults were also severely degraded (for several long periods of time in the history of the church, the choir was left without a roof structure), bricks at the base of the vaults were macerated even to a depth of 4-5 cm, and some areas of the extrados were also degraded to a certain depth. The situation was aggravated by the presence of adobe bricks in the masonry. These were totally macerated. The vault arches have not been properly interwoven, thus technological cracks appeared around the arches owing to inaccurate construction. Bigger cracks in the walls continued within the vault structure as well, precisely above the transversal arch. Cracks were completed and totally or partially re-bonded depending on bonding possibilities, without jeopardising the local or global stability of the vault. The re-bonded area of the transversal crack was further reinforced with triple layers of helical bars. The extrados of the vault was treated with lime based hydraulic mortar over which a layer of lime based hydraulic plaster was applied, reinforced with a special net of geogrid. Interventions were carried out in cooperation by a team of stonemasons, mural painting and stone restorers. Similar operations were conducted on the vaults over the lateral choirs and the sacristy.