Section 27-929.1. Retroactive requirements for office buildings one hundred feet or more in height

(a) General  requirements.  (1)  Notwithstanding  any other provision of this subchapter, all office buildings one hundred
  feet or more in height and buildings classified in occupancy group E one
  hundred  feet  or  more  in height in existence on the effective date of
  this subdivision shall  have  a  full  system  of  automatic  sprinklers
  installed  in  accordance  with this subchapter. Reports relating to the
  installation of such sprinkler systems shall be filed in accordance with
  subdivision (b) of section 27-228.5 of this  code  and  installation  of
  such  sprinkler systems shall be completed on or before July 1, 2019 or,
  if applicable, on  or  before  a  date  specified  by  the  commissioner
  pursuant to paragraph (2) of subdivision (b) of section 27-228.5 of this
  code.
    (2) Exception. Where an owner of a building or portion thereof subject
  to  such retroactive requirement demonstrates to the satisfaction of the
  commissioner that  the  installation  of  sprinklers  in  a  particular,
  limited  portion  of  such  building  is  not practicable, either due to
  structural conditions or because of designation as an interior  landmark
  by the New York city landmarks preservation commission, the commissioner
  may  waive  such  limited portions from the requirements of this section
  but may require additional fire safety measures to protect  the  health,
  safety and welfare of the public.
    (3)   Application  to  buildings  with  a  full  system  of  automatic
  sprinklers.   The provisions of this  subdivision  shall  not  apply  to
  buildings  in  existence  on  the  effective date of this subdivision in
  which a full system of automatic sprinklers was installed or required to
  be installed pursuant to any other provision of  law.  Nothing  in  this
  subdivision  shall  be construed to limit the applicability of any other
  provision of this code requiring sprinklers in the buildings referred to
  herein.
    (b) Converted buildings. Notwithstanding the foregoing provisions,  on
  and  after  the  effective  date  of  this  subdivision, no building one
  hundred feet or more in height shall be converted to an office  building
  or  to  a  building  classified  in  occupancy  group  E, whether or not
  application for such  conversion  is  required  to  be  filed  with  the
  department, unless a full system of automatic sprinklers is installed in
  such   building  in  accordance  with  this  subchapter  prior  to  such
  conversion.