Section 27-724. Construction required for or affecting the support of adjacent properties or buildings

Except  in  cases  where  a  proposed  excavation  will extend less than ten feet below the legally established
  grade, all underpinning operations and the construction  and  excavation
  of   temporary  or  permanent  cofferdams,  caissons,  braced  excavated
  surfaces,  or  other  constructions  or  excavations  required  for   or
  affecting  the  support  of  adjacent  properties  or buildings shall be
  subject  to  controlled  inspection.  The   details   of   underpinning,
  cofferdams,  caissons,  bracing, or other constructions required for the
  support of adjacent properties or buildings shall be shown on the  plans
  or prepared in the form of shop or detail drawings and shall be approved
  by the architect or engineer who prepared the plans.