Page 185 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

LEED Ener gy and Atmospher e 163

Options 2 and 3 Options 2 and 3 are not model based and therefore do not have a
method for applying on-site renewable energy sources to the point total for this credit.
Their prescriptive requirements are well outlined in the LEED-NC 2.2 and 2009 Reference
Guides.

Special Circumstances and Exemplary Performance
EAc1 is also listed with the EB icon, primarily because the construction assembly of
much of the exterior of the building impacts energy losses. In addition, the orientation
of the building is a significant portion of Option 1. Envelope treatments for energy
efficiency are different based on orientation and climate region of the country.
Figures 4.1.4, 4.1.5, and 4.1.6 are all of a new office and multipurpose building complex
in Houston, Texas. Figures 4.1.4 and 4.1.5 depict western exposure envelope treatments,
whereas Fig. 4.1.6 is of a southern exposure shading feature.
The Indoor Environmental Quality category promotes good indoor air quality, and
one of the strategies used to do this is increased ventilation, which often increases the
energy load. Ventilation strategies should be carefully evaluated in conjunction with
energy efficiencies and impacts to maintain an optimum balance between these two
goals.
There were no exemplary performance points associated with this credit in
version 2.2, but version 2009 allows one EP point for Option 1 as summarized for
exemplary energy performance reductions as noted in Table 4.1.1 (50 percent and
46 percent for new and existing buildings, respectively.)

FIGURE 4.1.4 Shell Woodcreek offi ce and multipurpose building complex in Houston, TX as
featured on the cover: Western exposure envelope treatments. (Photo taken November 11,
2009 by Heidi Brakewood.)