&EPA
United States
Environmental Protection Agency
Air and Radiation
Fall Conference Edition
Septembers, 2003
CHANGE FORTHE
BETTER WITH
ENERGY STAR
The quality of our
environment is everyone's
responsibility. ENERGY
STAR8 is a government-
industry partnership that
gives everyone the power
to reduce air pollution and
greenhouse gases through
energy efficiency—at work
and at home.
The ENERGY STAR
designates superior energy
efficiency in more than
35 categories of consumer
and business products
and superior energy
performance in qualifying
buildings and homes.
Learn more.
Visit www.energystar.gov.
For information on New
Building Design and
ENERGY STAR, e-mail
Karen Butler at
butler.karen@epa.gov.
ENERGY STAR*
New Building Design Case Study
RAFI Office Building, North Carolina, USA
The Rural Advancement Foundation
International-USA (RAFI-USA) is a private, non-
profit organization located in Pittsboro, North
Carolina. RAFI-USA promotes sustainability,
equity, and diversity in agriculture through policy
changes, practical assistance, market opportunities,
and access to financial and technical resources. In
1997, the Foundation's members needed a new
building to house its staff offices, rental offices
for like-minded non-profits, and space for a
conference center. They wanted a building that
would embrace their commitment to sustain-
ability and preserving the natural environment.
Project architect Alicia Ravetto envisioned a
sustainable building design, and she worked with
the building owner to reduce the environmental
impact of the new structure. Their strategies
included maximizing energy performance to
reduce greenhouse gas emissions, managing
water consumption required for staff use and
landscaping, using finishes and materials low in
volatile organic compounds to improve the
indoor air environment, and recycling materials
from the existing building to minimize landfill
debris during construction. The resulting energy-
efficient "green" building provides a pleasant and
productive working environment for employees.
Teamwork from the Start
A full-day design charrette (brainstorming
meeting) was conducted at RAFI's site in
downtown Pittsboro. Participants included
architects, engineers, RAFI staff and board
members, municipal officials, and community
leaders. They did a walk-through of the
2.8-acre site to analyze land features, and toured
the 1830 two-story building to evaluate options
for reusing the aged structure. Afterwards, they
gathered under massive old oak trees and
produced a list of priorities that later became part
of the building program.
Dan Pollitt Conference Center — Southwest view.
Effective building shape, location, and orientation optimize
energy efficiency with increased daylighting and passive solar
opportunities.
Materials, Land Use, and Natural Light
The design team focused on the re-use of
materials and the building's siting and orientation
to fulfill RAFI's commitment to sustainability.
The existing structure was carefully deconstructed
and all re-usable materials were incorporated
in the new one. To minimize site impact, the
architect located the new building on the existing
footprint and preserved mature hardwood trees.
Driveway and parking areas were designed to
minimize storm water runoff by using gravel
instead of impervious surfaces. The new one-story
design was elongated on the east-west axis to
maximize natural lighting in the offices and
meeting rooms. All offices were designed to face
south and be supplemented by ambient indirect
and task lighting.
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" Setting an energy
use target at the
outset, simulating
energy use,
design and
construction,
tweaking designs as
necessary kept the
RAFI building on
track to achieve its
energy performance
goal."
Energy Efficiency Leads to Energy
Performance
Alicia Ravetto incorporated energy efficiency strategies
that would achieve the performance goal established
for the RAFI project. She set an energy use target
early in the design, which helped her focus the
discussions with engineers. They used the target as a
guide to determine lighting power density and to
select an HVAC system that would meet the needs of
the building and not be oversized. Ms. Ravetto used
Energy 10, an energy simulation software program,
to model the building's consumption and evaluate
various energy efficiency measures. As changes were
made that affected energy use, the design team
monitored the process to ensure that RAFI's goal was
achieved.
The most effective energy strategies were daylighting,
passive solar, energy-efficient lighting, natural cross
ventilation, R-19 insulation in the walls and R-30
- Alicia Ravetto, AIA insulation in the ceiling, and a high efficiency HVAC
system. Energy simulation indicated that these
techniques would reduce lighting loads by 70 percent,
cooling by 50 percent, and minimize heating
requirements, compared to the baseline building. Ms.
Ravetto subsequently compared her design target to
the actual energy performance of similar buildings,
using the Environmental Protection Agency's (EPA)
online software tool—Target Finder. Target Finder
ranked the energy performance, predicted by the
energy modeling, among the top in its class.
The Benefits
In July 2002, once the facility had been operating for
one full year, Ms. Ravetto benchmarked the new
building's actual energy performance using EPA's
online energy performance rating system. This rating
compares the energy use of an existing building
against a national database of similar facilities. RAFI-
USA scored a 90 out of 100, distinguishing it as the
first office building in North Carolina to earn the
prestigious ENERGY STAR®. Annually, it consumes
25.1 kBtu/SF and costs $0.60/SF to operate. The
architect and owner are delighted that the design
energy target came very close to the building's actual
energy use. By managing resources and implementing
energy-efficient strategies, the RAFI building prevents
the emission of 300,000 pounds of carbon dioxide
compared to an average facility. The environment
benefits and so do the occupants.
Target Finder-Your
Tool for Setting an
Energy Use Target
Use Target Finder during:
• design to set an energy
use goal
• schematic design to
regularly evaluate the
effectiveness of energy
efficiency strategies.
EPA's Target Finder, a
software tool available on
the ENERGY STAR Web
site, assigns an energy
performance score
(1 to 100) to your design
energy consumption and
the target, making it easy
to compare the two. The
scoring system helps
designers see how their
design energy ranks on
the scale from best to
worst performing
buildings. Target Finder's
energy use intensity is
derived from actual
energy consumption
data.
Conference room with South-facing clerestories for daylighting.
Interior daylighting with supplemental energy-efficient lighting
reduces long-term operating costs and improves indoor environ-
mental quality.
"Energy analysts often speak of a building's
performance in terms of the energy it uses,"1 while
the purpose of a structure is usually to serve human
needs. "The building should offer an environment
conducive to helping occupants be more productive
in whatever type of work they are engaged in."
In RAFI's new building, employees benefit from
daylighting, natural cross ventilation, and individually
controlled temperature and airflow. These features
contribute to a productive, comfortable working
environment. Such an achievement is truly an invest-
ment in the environment through sustainability, as
expressed in the Foundation's mission statement and
delivered by the architect's design.
"/ think Target Finder is a wonderful tool
for the very early stages of design; I
encourage all architects and designers to
use it. Target Finder is a fast and easy
way to establish your new building's
energy use target from a national
database of actual consumption."
— Alicia Ravetto, AIA
1 Krepchin, Ira. Integrated Building Design. Esource. September 2000.
09/08/03
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