Sustainable design principles shall be applied to the siting, design, and construction of such
buildings. Not later than 90 days after
December 19, 2007, the
Secretary, after reviewing the findings of the Federal Director under
section 17092(h) of this title, in consultation with the Administrator of General Services, and in consultation with the
Secretary of Defense for considerations relating to those facilities under the custody and control of the
Department of Defense, shall identify a certification system and level for green
buildings that the
Secretary determines to be the most likely to encourage a comprehensive and environmentally-sound approach to certification of green
buildings. The identification of the certification system and level shall be based on a review of the Federal Director’s findings under
section 17092(h) of this title and the criteria specified in clause (iii), shall identify the highest level the
Secretary determines is appropriate above the minimum level required for certification under the system selected, and shall achieve results at least comparable to the system used by and highest level referenced by the
General Services Administration as of
December 19, 2007. Within 90 days of the completion of each study required by clause (iv), the
Secretary, in consultation with the Administrator of General Services, and in consultation with the
Secretary of Defense for considerations relating to those facilities under the custody and control of the
Department of Defense, shall review and update the certification system and level, taking into account the conclusions of such study.