law: 164. Power to require entry in assessment list of details of buildings.
  (1) For the purpose of obtaining a partial remission or refund of tax, the owner of a building composed of separate tenements may request the Commissioner, at the time of the assessment of the building, to enter in the assessment list, in addition to the rateable value of the whole building, a note regarding any detail of the rateable value of each separate tenement.
  (2) When any tenement, the rateable value of which has been thus separately recorded, has remained vacant and unproductive of rent for sixty or more consecutive days, such portion of any tax assessed on the rateable value of the whole building shall be remitted or refunded as would have been remitted or refunded if the tenement had been separately assessed.