The smaller building in front of the abbey church Link is the only part of the complex which preserves features from monastic times (i.e. from before the Scottish Reformation of 1560). It is known as Place of Paisley, where "place" is derived from "palace". This photo was taken from the riverside path where it meets Cotton Street.
That's a strange arrangement of drain pipe branches there. Some are running up to the main pipe and others are horizontal. I wonder what's inside the building that requires or enables such an arrangement?