Page 314 - The Engineering Guide to LEED-New Construction Sustainable Construction for Engineers

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6.6 IEQ Credit Subcategory 6: Controllability of Systems
The intention of this subcategory is to allow the building occupants greater control over
both lighting and thermal comfort. Not only may it aid in indoor environmental quality
and comfort for the occupants, but also if used wisely, it may save on energy costs.

IEQ Credit 6.1: Controllability of Systems—Lighting
This credit allows for greater occupant control over the lighting where one works or
performs regular tasks. IEQc6.1 is worth one point in both LEED 2.2 and LEED 2009.
LEED-NC 2.2 lists the Intent, Requirements, and Potential Technologies and Strategies
for IEQc6.1 as follows and is consistent with the LEED 2009 intent and requirements:
Intent
Provide a high level of lighting system control by individual occupants or by specific
groups in multi-occupant spaces (i.e. classrooms or conference areas) to promote the
productivity, comfort and well-being of building occupants.
Requirements
Provide individual lighting controls for 90% (minimum) of the building occupants to enable
adjustments to suit individual task needs and preferences.
AND
Provide lighting system controllability for all shared multi-occupant spaces to enable
lighting adjustment that meets group needs and preferences.
Potential Technologies and Strategies
Design the building with occupant controls for lighting. Strategies to consider include
lighting controls and task lighting. Integrate lighting systems controllability into the overall
lighting design, providing ambient and task lighting while managing the overall energy use
of the building.
Calculations and Considerations (LEED 2009)
This requirement has two parts that must both be met. The first is for the regular
occupants of the building at their daily workstations, and the second is for shared spaces
that may be used periodically by regular occupants and also by transient occupants. The
definitions from the LEED-NC 2.2 Reference Guide for individual occupant spaces,
nonoccupied spaces, nonregularly occupied spaces, and shared (group) multioccupant spaces can
be found in App. B and are consistent with the LEED 2009 definitions.
Individual Control The first requirement is that 90 percent of the occupants have control
over their task lighting at their typical workstation or living space. Task lighting can be
permanently wired or can be portable lighting, such as desk lamps. For commercial or
institutional uses, typical workstations can be seen as individual offices, desks or tables
in cubicles, booths, and other usual locations where an employee performs most of his
or her work. To determine the occupancy for these nonresidential uses, it would be
most appropriate to start with the full-time employee equivalents (FTEs) as defined in
the Sustainable Sites category in Eqs. (2.4.2) and (2.4.3), for the following definitions:
FTE Full-time equivalent occupant during shift j
j
FTE Full-time equivalent occupancy of employee i during shift j
j,i
FTE = ∑ FTE for all employees in shift j (2.4.2)
j j,i
FTE = Maximum FTE (2.4.3)
j