62 - Key space.

§ 62. Key  space.  All  ceilings,  stud partitions and furred walls in  tenements, apartments, hospitals, schools, and  other  public  buildings  where  plastered  with  lime  on  wood  lath  shall  have  not less than  three-eighths space between lath. All grounds and jambs shall  mean  not  less than seven-eighths from the stud.