The western wall presents provisions similar to those of the north and south walls: it is cut out in three spans separated by buttresses and posts. It does not comprise however a window, at least for its low part. Two sets of bases of posts are preserved perfectly on the north of the wall: they show that the style of construction is Norman. Nothing indicates to this level that it is a Jewish monument.
The wall presents avery accentuated degradation aspect. There are traces of a violent fire. The archaeological observations indicate that this fire took place in the first decades of XIIth century. It is certainly about the fire of 1116 noted in a chronicle of the Cathedral of Rouen. This fire, in addition to a rise in the level of the ground by about twenty centimetres around the monument, encouraged certainly the inhabitants with prudence, involving the modification of the entry on the southern face.