Section 27-297. Exemptions

The following constructions shall be exempt from
  the provisions of section 27-296 of this article:
    (a) One- or two-family  dwellings.  One-  or  two-family  detached  or
  semi-detached  dwellings  of  two  stories  or  less  in  height and two
  thousand five hundred square feet or less in area located within  zoning
  residence  districts may be constructed or reconstructed of construction
  groups II-D combustible materials, or if damaged for any cause, only the
  damaged portions shall be required to be  reconstructed  to  conform  to
  II-D  construction.  In  addition,  one-family  dwellings located within
  zoning residence district anywhere in the city, may  be  of  combustible
  group  II-E  construction in conformance with the area and height limits
  established by tables 4-1 and 4-2.
    (b) Fences. Fences not over six feet high may be erected  of  wood  or
  other combustible material.
    (c)  Storm enclosures, bay windows, etc. Storm enclosures, bay windows
  and similar appendages may be constructed of  combustible  materials  in
  accordance  with  the  provisions  of  section 27-336 of article four of
  subchapter five of this chapter.
    (d) Accessory buildings for open parking lots. Parking lot offices and
  similar accessory buildings not more than ten feet  high  and  not  more
  than  one  hundred  fifty  square  feet  in  area  may be constructed of
  combustible materials when on the same lot or accessory to  a  lot  used
  for  motor  vehicle parking, and when located at least six feet from any
  lot line or building.
    (e) Temporary structures. Temporary platforms, reviewing  stands,  and
  similar  miscellaneous  structures  may  be  constructed  of combustible
  materials and used for a limited period of time, subject to the approval
  of the commissioner.
    (f)  Greenhouse.  Greenhouses  may  be  constructed   of   combustible
  materials  when  accessory  to a one- or two-family dwelling on the same
  lot and when located at least six feet from any lot line or building.
    (g) Roof structures. Cooling towers, antenna supports, and other  roof
  structures  may  be  constructed  of combustible materials in accordance
  with the provisions  of  section  27-338  of  subchapter  five  of  this
  chapter.
    (h)  Bins,  tanks,  and  towers. Coal and material bins, water towers,
  tank structures, and trestles may be constructed of  wood  planking  and
  timbers  of  dimensions  not  less  than  as  required  for  class  II-A
  construction when not over thirty-five feet high and having an  exterior
  separation of a least thirty feet.
    (i)  Signs.  Ground signs, wall signs, roof signs, and temporary signs
  may be constructed  of  combustible  materials  within  the  limitations
  established in article eighteen of subchapter seven of this chapter.