Page 123 - Zero Net Energy Case Study Buildings-Volume 3

LACCD HARBOR COLLEGE SCIENCE BUILDING
CASE STUDY NO. 16
Building Envelope
One of the design strategies was simply to take advantage of the year-round benign climate and eliminate conditioned circulation space such as corridors and lobbies. Classrooms and labo- ratories open directly on to exterior circulation space. This also assists in the design of natural ventilation, which is utilized in all the non-laboratory spaces. (See photo on the following pages.)
A second principal strategy was to integrate sun-shading of the south façade with the solar PV panel installation. The support structure is the “signature” architectural design feature, encom- passing both the façade and the roof as it wraps up and over the building, while providing a sizable area for the PV panels. Care was required to maintain sufficient daylight to the occupied spaces on the south side of the building.
The exterior wall consists of standard construction metal studs and R-19 insulation. No continu- ous insulation layer is utilized to prevent heat transfer due to “thermal bridging”, primarily be- cause of the excesive impact of first-cost. The roof has uses R-30 insulation in the roof assembly detail. See below for a typical wall section.
(Above) The structure sup- porting the solar PV panels provides in addition the sun- shading on the south facade while allowing daylight pen- etration to the spaces on that side of the building. (Photo: Tim Griffith).
(Opposite Page, Top) Aerial view of the Harbor College campus from the east in 2009. Site of the future Science Building is circled in red. Solar PV arrays are visible beyond on canopy structures above the parking areas.
(Opposite Page, Bottom)
Aerial view of the Science Building from the north.
(Overleaf) View of the outdoor circulation areas, with the solar PV support structure vis- ible above and to the right.
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