A large nave 8 meters wide and two small side naves 4 meters wide, which makes 16 meters for the total width. Height of the bell tower: 30 meters. Total length of the building: 36 meters, choir included, not including the tower. Height of the large nave, from the pavement to the keystone: 13 meters. Height of the small naves: 11 meters 50. The central nave including the transept not very visible inside has 5 bays separated by very beautiful palmate pillars: the last, longest, constitutes the forechoir, its last doubleau serving as a triumphal arch whose supports support the side altars of the arms of the transept. The 5 bays are ribbed with doubleaux, a pointed arch opening giving onto the side aisles replacing the formerets. These 5 bays are found in the side naves, also vaulted with ribbed vaults and doubleaux, but without formerets against the walls, plus two small bays framing the tower which is in the work. The heart has a bay identical to those of the central nave and an odd polygonal apse with 5 sides separated under the vaults by 6 ribs meeting at an axial keystone. Extract from the article From the origins of Saizerais at the dawn of the XNUMXth century by Samuel Germain in http://www.saizerais.fr/le-village/histoire-de-saizerais/