The new building also had three aisles with a transept and a choir shaped like the earlier choirs. A crypt was now built below the choir. The choir was closed with a semi-circular apse, which was encased within a half decagon. A two-story outer crypt was connected to the choir, the west walls of which formed the east walls of the side choirs. Towers next to the altar room gave direct access to the crypt. The near choirs contained matronea, which were open to the transepts and the main choir. the outer walls of the ends of the transepts were made two stories high, with the upstairs portion composed of three niches with windows. On the ground floor were niches, and the pattern of niches continued on the side walls. A walkway ran along the walls above these niches, leading to the matroneum galleries. The double bay between the westwork and the nave was maintained. The structure of the nave walls is unknown, but reconstructions based on other churches, especially Susteren Abbey which appears to draw from the new Ottonian church in many aspects, assume an interchange of piers and columns. There were probably wall paintings between the arcades and the windows on the walls, since remains of wall paintings have been found in the westwork. Outside, the clerestory of the nave had a structure of pilasters and volute capitals, probably with twelve windows. The belief that the unknown architect of Essen Abbey church was one of the best architects of his time is based particularly on the westwork, which even today is the classic view of the church. As in the earlier churches, the westwork is only a little wider than the aisles of the nave. From the outside, the westwork appears as an almost square central tower crowned by an octagonal belfry with a pyramidal roof. At the west end there were two octagonal side towers, containing staircases to the belfry, which reached to just below the bell story of the belfry. The bell story of the central tower and the uppermost stories of the side towers have arched windows. Two story side rooms with arched windows on the upper floor are attached to the north and south sides of the central tower. On the ground floor of these side rooms, doors set in niches lead into the church – the central entrance of the earlier church was abandoned and a large, round-arched window installed in its place.