
Note the open structure of the alternating floor. This pretty 
  much garentees a constant cold wind blowing round and through the stucture. 
  Also the open central shaft means that every where is wet except for the roof 
  of the flats below. Children residents and down and outs can be found huddled 
  in the shelter of the walls near the lifts/ stair wells. Or playing on the roof 
  areas. 
  As a result, any one in the flats themselves, can hear the sound of feet running 
  across the ceiling.
  The bottom of the central shaft could be used for a number of jobs. It may contain 
  a small rusting childrens play ground. Or may be used as a car park. Most likely 
  it is simply waste ground and used as a rubbish dump by the residents.
  There is a small chance that one of teh ground floor flats contains a