The slype was a passageway leading from the cloister to the cemetery, and much white-washed. It continued east beyond the edge of the Chapter House, and may have been a covered passage from this point onwards. It dates from the 14th century and had a door at each end, so it probably served as a Parlour. There was also a small door in the south wall leading to the Common Room. The north wall was at some date doubled in width to five or six feet wide with a joint down the centre. The passage itself was more than seven feet wide, and 125 feet long from the doorway level with the east wall of the common room. This takes it into the abbey field, in the direction of the Infirmary.

As we have seen, a door led from the slype into the Common Room, the north wall of which was a continuation of the north wall of the refectory and the slype between those two rooms. There was also a direct entrance from the cloister into the Common Room.

The Common Room was the only room in the abbey which was heated, hence its other name of Warming House or Calefactory. Canons used the room in order to keep warm, to drink wine or take other dietary indulgence (which would include any meat), to grease their shoes, and to let blood. It is perhaps because it was so useful that it was built early: it dates from the 13th century.  

The room was vaulted and had windows on its east side, one of which has a well-preserved drain in its sill, with a stone pipe running through the wall. Next to this window was the big fireplace found in 1879. The exterior wall here has a very bold and well preserved Early English base moulding carried round the projecting chimney. The octagonal stone top of the chimney itself was found in clearing the earth in the 1878 excavation, but the south west of the room was not excavated because it lies under the White Cottage’s garden.

Over the sacristy, the slype. the two western bays of the chapter house and the common room was the canons’ dormitory, with access to the church via a stone night stair, the bottom couple of steps of which can still be seen. The dormitory also was built early in the Abbey’s life. In the 1230s Henry III gave 11 oaks for shingles for the dormitory roof. Even with the museum occupying the site of the Chapter House, it is difficult to imagine the buildings on the east side of the cloister and stretching off into White Cottage’s garden: south transept, sacristy, chapter house, slype, common room and reredorter. What is even more difficult is to realise that most of these buildings were two stories high. That the canons’ dormitory was at first floor level explains the presence of the night stair in the south transept: it was the staircase the canons used to descend from the dormitory for services during the night.