Page 116 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

LEED Sustainable Sites 97

11 p.m. to 5 a.m. 50% reduced power
to luminaires with direct line of
sight out building openings

Interior or
11 p.m. to 5 a.m. luminaires with direct
line of sight out building openings
require shielding at the openings.
and

Do not exceed the maximum LPD
LIGHT POLLUTION
REDUCTION Exterior Part 1 requirements for all the exterior
lighting from ASHRAE90.
1–2007 Table 9.4.5
and
Limit Horizontal Illuminance
at Property Boundary
and
Exterior Part 2 Limit Vertical Illuminance
and at Property Boundary
and Limit Horizontal Illuminance
Beyond Property Boundary
Illumination Restriction
Upward (MIDAL)

FIGURE 2.8.2 Summary of light pollution reduction credit for LEED 2009.

2.9 Discussion and Overview
Sustainable Site credits may sometimes be mutually exclusive, and some of them may never
be applicable to a project or site. For example, if none of the available sites are brownfields,
then there is no possibility of obtaining SS Credit 3. However, some seemingly opposing
credits may actually be achievable for the same site. For instance, SS Credit 1 encourages
spaciousness by keeping certain special areas undeveloped, whereas SS Credit 2 encourages
denseness for more efficient use of infrastructure. However, many of the urban areas applicable
for SS Credit 2 already meet the six criteria in SS Credit 1 as the area has already been developed
and these special resources no longer, or never did, exist. What may be more difficult is to find
a situation where both SS Credits 2 and 5 can be met. It may seem very difficult to promote
dense urban development and yet create open space, but it is not impossible, especially when
the parameters of the project allow for multistory structures. In addition, both SSc5.1 and
SSc5.2 have modified requirements in dense urban environments to encourage open space
but in a different manner as may be more readily doable in this environment.
It would be very difficult to meet SSc2 in the United States for a traditional retail
grocery store, as U.S. customers usually use large shopping carts throughout the
structure for shopping for their foodstuffs which are not made for stairwells and
escalators. However, in other countries such as Switzerland and Norway, there are