Rating System

LEED BD+C: New Construction, LEED BD+C: Core and Shell

Rating System Version

v2 - LEED 2.2, v2 - LEED 2.0

Inquiry

At over 2 million GSF, Beijing Parkview Green (PVG) is one of China\'s largest sustainable architecture projects. PVG is comprised of four buildings, including two 11-story and two 20-story towers that house retail area, offices and a six-star hotel - all of which are enclosed in a pyramid-shaped "Microclimatic Envelope" (ME) comprised of glass and plastic (ETFE - ethylene-tetrafluoroethylene). The glass forms the vertical portions of the ME, while the horizontal sloping elements are constructed of ETFE. As a separate, non-structurally tied edifice, the ME operates in concert with the buildings at the site, providing benefits in energy conservation, solar reflectance, and stormwater management, while providing insulation value to the structures within. If you think of a glass covering on a cake stand, you have a pretty good idea of the nature of the ME. Although the ME is not a "roof" in the traditional sense, we are seeking an interpretation that it be considered one in the context of this credit. The ETFE portion of the envelope contains an interstitial layer of ETFE that is coated with a series of silver dots to achieve a high albedo, rendering the ECM more effective at rejecting unwanted heat, while providing near natural lighting levels to the environment below. Thus, we propose to use the reflectance and emissivity characteristics of the ETFE envelope as the project "roof" element that affects the project\'s urban heat island effect in lieu of the roof structures on each of the four buildings enclosed by the ME. We believe this makes the most sense, as it is the first physical element that sunlight encounters and will be the physical element that radiates heat (or not) into the ambient environment.