Section 27-511. Separation

No  tent  or  air-supported structure shall be
  erected closer than twenty feet to any interior lot line nor closer than
  thirty feet  in  any  direction  to  an  unprotected  opening,  required
  exterior  stairway or corridor, or required exit door, on the same level
  or above the level of the tent or air-supported  structure.  A  tent  or
  air-supported  structure  may  abut  another building on the same lot if
  there are no unprotected openings or exits above or within  thirty  feet
  as above stipulated, if there is no door between them that is a required
  exit, and if the exterior wall separating them meets the requirements of
  subchapter five of this chapter for fire divisions.
    Exceptions.  Requirements  for  separation from other buildings on the
  site shall be waived where a tent or air-supported structure is used for
  on-site  temporary  shelter  for  construction   work,   or   incidental
  fabrication  of  construction  elements  to  be  used  on  the  site  of
  construction.