Under the version three LEED (Leadership in Environmental Engineering and Design) standards, the Green Building Certification Institute assumed administration of LEED certification for all commercial buildings.  LEED for Existing Buildings (“LEED-EB”) employs sustainable performance standards to measure an existing building’s environmental impact and outlines means for reducing those impacts over time.  The LEED for EB Rating System helps building owners and managers measure operations improvements and maintenance on a consistent scale with the goal of optimizing operational efficiency and, hence, minimizing adverse impacts on the environment.

In the past, most LEED rating systems required a high building occupancy to warrant a rating – 75% – an argument founded on the idea that under-occupied buildings would earn an unrealistic score on what are critical scoring attributes.  Among these attributes are: operating costs; waste sent to landfills; energy and water usage; and greenhouse gas emissions – all of which would be reduced in a lower occupancy environment.  LEED for Existing Buildings addresses whole-building cleaning and maintenance issues, so the entire building is considered part of teh examination process.  The unintended consequence of the high occupancy requirement was to disqualify and eventually discourage a high number of properties from pursuing LEED certification, a concept anathema to the intent of LEED certification.

LEED CertifiedFinding this unintended consequence untenable, the LEED Steering Committee recently approved a change to the Minimum Program Requirements for LEED for Existing Buildings lowering the occupancy rate required for certification from 75% to 50% occupancy.  The US Green Building Council staff and LEED committee members have confirmed that the occupancy reduction does not undermine the technical integrity of LEED for Existing Buildings.  The hope is that more buildings will take on LEED certification, even in a struggling economy.

For guidance on how LEED for Existing Buildings projects can demonstrate compliance with the minimum occupancy requirement click here. To access an informative microsite detailing how to properly gain LEED certification for existing buildings, register here.