The Concèze murals were rediscovered during preparatory research by JJ Sill, using surveys conducted by A. Carré in 1989. The decorations found are painted fresco on white stucco ("dealbatio" style). In the chorus, a painted section of double-jointed stone cutting (vertical) and double red bed (horizontal) can bee seen, decorated in stencil, with small black and red flowers. It dates from the Romanesque period and would have been a symbol of purification. There is a great deal of diversity, enriched with stylized lily flowers or geometric figures with in rosettes and clover leaves. Another section on the north wall of the north aisle cannot be from the Romanesque period, as the aisles were added in the 15th century. The pattern here has often been used over the centuries, making it difficult to attempt precise dating. Since the end of the Romanesque period more ornamental paint was used, highlighting the structure and architectural details (ribs, keystones, windows, etc.). In the 14th and 15th century, the beams of the nave were highlighted by decorations including false architectural elements such as brightly coloured keystones (red, yellow and blue-black), renovated later (perhaps in the 17th century) using extra pink and green. The superposition of the two eras is evident in the large arches of the main part of the nave.
The architecture of the building was updated in the 18th century style with decorative faux marble in red, yellow, blue, black and green: the speckle effects is also faux marble associated with "liernes" in the same tones. The walls were supposed to have been completed with interns, of which only a few fragments remain. On subsequent layers, probably from the eighteenth century, two funeral litters were added; high black plinths at the base of the west and south walls. The most recent layer before the commencement of work, consisted of a wash covering grey stone; it dated back probably to the late 19th or early 20th century.
Previous studies showed two main panels on the the nave (15th and 18th centuries). Two solutions were therefore considered: the juxtaposition of the two epochs or the development of a single setting. Favouring one period for the entire building was justified neither for reasons of pictorial coherence nor historically. The juxtaposition therefore seemed the most authentic archaeological choice; so it was chosen for the north aisle.
To recreate the atmosphere of the 18th century, the best preserved period, the south aisle was treated differently using a pictorial re-integration a trattegio.