Construction of the church itself started shortly after 1200, and it was consecrated in 1312, when part had become usable. From 1324 onwards the flying buttresses and revised choir structure acquired Brabantine Gothic characteristics, distinct from French Gothic. After the city fire of 1342, the Master Mason Jean d'Oisy managed repairs and continued this second phase, which by the time of his death in 1375 formed the prototype for that High Gothic style. His successors finished the vaults of the nave by 1437, and those of the choir by 1451.