The western part of the nave was mainly used by the lay-brothers, who performed 

most of the heavy manual and agricultural work within the estate but followed a less strict religious regime than their choir monk brethren. 

This section was divided from the rest of the church by a screen and would have housed the lay-brothers' altar. A piscina - the basin used for washing altar vessels is still visible in the south wall as well as the doorway through which the lay brothers entered this part of the church from the cloister. 

Beyond the screen, the eastern part of the nave and the area below the crossing tower formed the choir, used by the choir monks for their round of eight daily services. 

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