4. 3
1. Executive summary
The following thesis illustrates the sustainable design case study of the
extension for the Peter Kiewit Institute, head office of the College of
Engineering and College of IS&T of the University of Nebraska in
Omaha, throughout the definition of design aspects such as materials,
building and mechanical technologies, focusing on the study of energy
efficiency and applying as implementing criteria and parameters LEED
guidelines (Leadership in Energy and Environmental Design) developed
by USGBC (United States Green Building Council).
The Peter Kiewit Institute was master planned for future modifications
and extensions, therefore due to the recent increase of students
enrollments, the University of Nebraska has decided to expand the
building applying principles of sustainable design and creating a so-
called “green building”. The project comprehends the extension of the
existing building in the south-east area, in order to create a unique
corridor connecting the two wings of the building eliminating every
discontinuity.
This will improve the flexibility and integrate the two colleges that occupy
the building and create potential new indoor outdoor views that augment
visual evidence to the visitor and the user that this is a high performance
environment of innovative research that leverages the collaborative
opportunities between the two colleges.
The new spaces will have to be designed with adaptation and flexibility
characteristics for future concepts of research and learning and meet the
requirements for LEED certification.
5. 4
The thesis will focus on the design of a building that meets and applies
the concepts of sustainability for the Materials and Resources, Energy
and Atmosphere categories. The objectives for the design are:
maintaining the concept of "building laboratory" which means, create a
complex in which students can observe the various building systems;
improve mentoring and counseling services for students with special
offices, providing new classrooms, laboratories, offices for university
staff; create spaces to host summer camps, seminars, workshops for
research in the fields of study offered by the institution; providing an
auditorium for conferences and
graduation sessions; promote the development of the South Pacific
University Campus equipping the building library service, thus reducing
urban traffic into and within the North Campus, where currently resides
the only university library. On the basis of a previously created
architectural model, the concepts mentioned above, a deeper
investigation will be conducted on the energy efficiency point of view, to
pursue a reduction of waste and energy consumption through the
appropriate selection of materials, construction methods and mechanical
systems, a reduction of the total quantity of raw construction materials,
privileging those with lowest environmental impact in terms of processing
and transportation, as well as the use of recycled building materials. The
research will try to provide a building that responds to the requirements
established by the Materials and resources and, Energy and
Atmosphere LEED credits system.
Since the extension architectural model of the PKI Institute was created
with Revit (Fig.1), on the basis of this draft hypothesize of the building
materials and construction systems. The first phase of the project will
6. 5
consist in making inquiries and gather information about sustainable
materials, construction and mechanical systems and analysis. Defined
materials and equipment, all the gathered data will be applied to the
building model with Autodesk Revit software, and a certain number of
energy simulations will be performed. The results will be evaluated in
order to identify the most effective measurement of efficiency and modify
the model parameters referred to materials to improve the building
energy performance.
Figure 1. Peter Kiewit Extension project and exiting building mass.
2. Introduction - Environmental Impact of
Buildings
The construction industry is a major contributor to the environmental
issue, because of the exploitation of nonrenewable materials resources,
land use, energy consumption related to all stages of the life cycle of a
building product and production of demolition waste.
Buildings generate impacts on the environment not only during its
construction, but also throughout the whole process, procurement and
7. 6
control of the raw materials, production and transport to the building
demolition and disposal of debris . On the other hand the use of the
building generates impacts in order to guarantee conditions of comfort
and inner well-being, thus interacting with the inhabitants needs and
providing them with a viable and adequate environment to the activities
that take place in them. Therefore it affects the creation of environmental
impacts, which occur both as consumption of resources as an
environmental pollution. The environmental impact of buildings is also
dominated by the use of energy demand for operation. However,
construction material impact (embodied impact) moves into focus to
construct increasingly energy efficient buildings. The choice of
constructional material influences the operational energy demand of
buildings. This is due to the differences in physical properties, such as
thermal inertia or resistance. The capacity to store thermal energy over
time differs greatly for different materials. For instance, wooden exterior
walls may have one-third of the active thermal mass in comparison to
brick or concrete walls, depending on the composition. This difference
may result in an increased space heat and cooling demand. The
influence of thermal mass on the heat balance depends on several
factors, such as the climatic conditions at the building location.
Buildings account for 40% of worldwide energy use which is much more
than transportation. Furthermore, over the next 25 years, CO2 emissions
from buildings are projected to grow faster than any other sector (in the
USA), with emissions from commercial buildings projected to grow the
fastest—1.8% a year through 2030.1
1
United States Department of Energy - http://energy.gov/
8. 7
In order to decrease environmental impact due to constructions,
sustainable architecture seeks to minimize the negative environmental
impact of buildings by efficiency and moderation in the use of materials,
energy, and development space, using a conscious approach to energy
and ecological conservation in the design of the built environment.
3. What is Green Building?
Sustainability is not just a one-time treatment or product. It is a process
applied to buildings, their site, interiors, their operations and the
communities in which they are situated. Sustainable building incorporates
planning, design, construction, operation and end-of-life recycling or
renewal of structures. A study conducted by the U.S. Environmental
Protection Agency (EPA), found that people in the U.S. spend on
average 90% of their time indoors. Occupants of green buildings are
usually exposed to lower levels of indoor pollutants and are generally
more satisfied of internal conditions given by lighting and air quality than
occupants in conventional buildings.
The resources used to create a building and the energy, water and
materials needed to operate it have a significant effect on the
environment and human health. In the United States building account for:
- 14% of potable water consumption
- 30% of waste output
- 40% of raw materials use
- 38% of carbon dioxide emissions
- 24% to 50% of energy use
9. 8
- 72% of electricity consumption
By building green environmental damage can be reduced and it can also
enhance the health of the environment and the people who live in it.
(New Building Institute: energy use intensities for sustainable designed
U.S. Government buildings 2015)2
. Further more Electrical generation
and distribution in the United States are very inefficient. Typical coal-fired
power plants are approximately 30% to 35% efficient, and distribution
losses are approximately 7% to 10%. Consequently, for every 10 units of
energy that go into a coal plant, only 3 to 4 units are actually delivered to
a home. Even more energy is required to mine and transport the coal to
power plants. Saving energy at the point of use significantly magnifies
the impact in terms of both efficiency and pollution reduction (Fig. 2). In
this example, you can see the overall efficiency of converting coal
(chemical energy) into light energy in the home. The total efficiency of the
system is the percent efficiency of each component multiplied together.
Figure 2. USA Electrical generation and distribution systems inefficiency in 2013.
2
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
10. 9
4. Green Building in the United States
4.1 A Brief History of Green Building in the US
Green building has its roots in the early solar builders, most of whom
began working during the first oil crisis in the late 1970s. Although the
scale of the solar movement was limited through the 1980s and early
1990s, many industry leaders worked on research projects involving
high-performance buildings that helped to establish the core concepts of
building science, a key component of green building.
One of the first organized green home programs to appear was in Austin,
Texas, where Austin Energy, the city-owned electric utility, recognized
the need to reduce electricity demand to avoid the construction of
another power plant. Austin Energy’s residential energy efficiency
program was founded in 1985 and, in 1991, evolved into Austin Energy
Green Building®. Through the 1990s, several more local programs
appeared, including Built Green® Colorado, Built Green® Washington,
and Earth- Craft HouseTM.
In 1995, the U.S. Environmental Protection Agency (EPA) introduced the
ENERGY STAR for Homes program. This certification provides owners
the assurance that their homes are more efficient than standard
construction. ENERGY STAR strictly evaluates the energy efficiency of a
home and was not designed as a green building program. The EPA
originally developed the ENERGY STAR program to certify energy-
efficient electronics and appliances. Today, over 50 different types of
products may achieve the ENERGY STAR certification, and the logo is
11. 10
one of the most recognized brands in America.
In the late 1990s and early 2000s, local green home certification
programs began appearing across the United States. Approximately 100
different local and regional programs are currently available throughout
the country (Table 1.5). Filling a void in the marketplace, these green
building programs essentially became the definition and identity of green
building nationwide. The U.S. Green Building Council (USGBC) was
established in 1993 and released its Leadership in Energy and
Environmental Design (LEED) program in 1998. 3
(Fig.3)
Figure 3. USGBC fields of intervention.
This national green certification program launched a rating system that
takes into account the eight principles of green building (as previously
discussed, but with different labels and category groupings) within the
3
Green Building - Principles & Practices in residential construction - Abe Kruger, Carl Seville,
Delmar Cengage Learning, 2013.
12. 11
context of all types of commercial construction. Today, the USGBC
comprises 78 local affiliates, more than 20,000 member companies and
organizations, and more than 100,000 LEED Accredited Professionals.
USGBC introduced the pilot version of LEED for Homes in 2004, and the
program was officially released nationally in 2008. LEED for Homes is
designed to be among the most stringent green home programs, aiming
this program at the top 25% of builders in the United States. In
2005, the National Association of Home Builders (NAHB) released NAHB
Model Green Home Building Guidelines, a book designed to provide
builders with guidance on making their projects green. In 2007, the
NAHB and the International Code Council (ICC) partnered to develop the
National Green Building Standard. In 2008 the NAHB Research Center
began certifying homes under the guidelines through the NAHB Green
program. The American National Standards Institute (ANSI)–approved
ICC 700-2008 National Green Building Standard for single and
multifamily homes, residential remodeling projects, and site development
projects. The NAHB Research Center began certifying single and
multifamily homes and renovations under the new standard in 2009.
Certification under the original 2005 Green Home Guidelines was
discontinued in 2010. As energy codes become more stringent, higher
performance homes will become standard. Some states, particularly
California, have rigorous energy codes and emissions limits for building
materials that are designed to improve indoor environmental quality. As
people learn more about the benefits of green homes, the demand for
green building will continue to increase. Many industry leaders believe
that basic green building will ultimately become the minimum standard,
13. 12
and “green” as a differentiator will begin to fade away. This transition,
however, will likely evolve slowly over many years.
4.2 Green Building industry
Most of the green building elements aren’t new, in fact, before the wide
spread of fossil fuel use for energy and transportation, builders used
principles of passive design by capturing sunlight and wind for natural
lighting, heating and cooling. Sustainable buildings represent a return to
low-tech solutions by using high-tech technology. Green building is about
combining solutions to build an environment that integrates the best of
the new and old.
The USGBC was formed in 1992 and soon after it was formed it begin
developing LEED (Leadership in Energy and Environmental Design) for
rating and certifying the sustainability of buildings in the United States.
Experts identified characteristic and performance levels to define a green
building. The first LEED rating system was launched in 1999 and in the
decade that followed, it developed rating systems for the entire lifecycle
of the built environment.
14. 13
5.5 LEED rating system overview
Leadership in energy and environmental design (LEED)
LEED is a third-party green building certification program and the
nationally accepted benchmark for design, construction, and operation of
high-performance green buildings and neighborhoods. The rating
systems give building owners and operators the tools they need to have
an immediate and measurable effect on their buildings’ performance. By
promoting a whole-building approach to sustainability, LEED recognizes
performance in location and planning, sustainable site development,
water savings, energy efficiency, materials selection, indoor
environmental quality, innovative strategies, and attention to priority
regional issues. Additionally, LEED addresses all building types through
different rating systems and rating systems adaption.4
5.1 Rating system development and evolution
Since its launch in 2000, LEED has been evolving to address new
markets and building types, advances in practice and technology, and
greater understanding of the environmental and human health impacts of
the built environment. These ongoing improvements to LEED are based
on principles of transparency, openness and inclusiveness involving
volunteer committees and working groups, as well as USGBC, staff and
approval by a membership-wide vote.
LEED is updated through a regular development cycle for revisions to the
rating system. There are three basic types of LEED development:
4
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
15. 14
● Implementation and maintenance of current version. LEED
rating systems are continually improved through the correction and
clarification of credit language. These updates are published as
quarterly addenda and include LEED interpretations (see below).5
● LEED rating system adaptations. Credit adaptations address
both specific space types and international projects, meeting the
needs of projects that would otherwise be unable to participate in
LEED. Currently, four adaptations are available.6
● Next version of LEED. A periodic evaluation and revision process
leads to comprehensive improvement of the rating systems. This
phase includes multiple avenues for stakeholders input and final
approval by USGBC members. The ideas generated during the
development of next-version LEED credits are often pilot-tested by
LEED project teams prior to ballot.7
Additionally, the LEED Pilot Credit Library plays an important role in the
evolution of LEED. Pilot credits are tested across all rating system types
and credit categories and include credits proposed for the next version of
LEED. Project teams may attempt any of these pilot credits under the
Innovation categories and earn points by providing USGBC with
feedback on the credits’ efficiency and achievability. USGBC collects and
integrates this feedback to refine the pilot credits, and worthwhile credits
are then added to the balloted LEED rating system.
5
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
6
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
7
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
16. 15
Life cycle costing
Green building consider the life cycle approach, which means all the life
of the building is taken into consideration. It starts with pre design
decisions that set goals and a program to follow. It continues with
location selection, design, construction, operations and maintenance,
refurbishment, and renovation. (Fig.4) A building cycle ends with
demolition or preferably reuse. Life cycle costing looks at purchase and
operating costs as relative savings over the life of the building or product.
It calculates payback period for first costs, providing a context for making
decisions about initial investments. LCC can be used in comparing
alternatives with different initial and operating costs.8
For a building this
usually includes different types of cost:
● initial purchase, acquisition, or construction
● fuel
● operation, maintenance and repair
● replacement
● disposal (or residual value for resale or salvage)
● finance charges
● other intangible benefits or costs
Goals
Avoid contributing to greenhouse gas emissions
Reduce greenhouse gas emissions by 30% by 2030
Reduce the amount of fossil fuels used in mechanical systems
8
National Renewable Energy Laboratory - US Life-Cycle Inventory Database,
htto://www.nrel.gov/lci/
17. 16
Figure 4. The life cycle of a home.
LEED rating systems
Comprehensive and flexible, LEED is applicable to buildings at any stage
in their life cycles. New construction, ongoing operations and
maintenance of an existing building are all addressed by LEED rating
systems. The rating systems and their companion reference guides help
teams make the right green building decisions for their projects through
an integrated process, ensuring that building systems work together
effectively. Through an integrated process, ensuring that building
18. 17
systems work together effectively. Through a consensus-based process,
the rating systems are continually evaluated and regularly updated to
respond to new technologies and policies and to changes in the built
environment. In this way, as yesterday’s innovation becomes today’s
standard of practice, USGBC and LEED continue to push forward market
transformation. The following project types and scopes are addressed by
LEED rating systems:9
● LEED for New Construction and Major Renovations
● LEED for Core and Shell
● LEED for Commercial Interiors
● LEED for Schools
● LEED for Healthcare
● LEED for Retail
● LEED for Existing Buildings: Operations and Maintenance
● LEED for Neighborhood Development
5.2 Rating system structure
The LEED rating systems consist of prerequisites and credits.
Prerequisites are required elements or green building strategies that
must be included in any LEED-certified project. Credits are optional
elements that projects can elect to pursue to gain points toward LEED
certification.
Achieving LEED certification requires satisfying all prerequisites and
earning a minimum number of credits. Each LEED rating system
corresponds to a LEED reference guide that explains credit criteria,
9
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
19. 18
describes the benefits of complying with the credit, suggests approaches
to achieving credit compliance.
Although the organization of prerequisites and credits varies slightly
depending on the building type and associated rating system, LEED is
generally organized by the following broad concepts:
● Sustainable sites. Choosing a building’s site and managing that
site during construction are important considerations for a project’s
sustainability. LEED credits addressing sustainable sites
discourage development of previously undeveloped land and
damage to ecosystems and waterways; they encourage regionally
appropriate landscaping, smart transportation choices, control of
stormwater runoff, and reduced erosion, light pollution, heat island
effect, and construction related pollution. LEED also emphasizes
location and transportation issues by rewarding development that
preserves environmentally sensitive places and takes advantage of
existing infrastructure, community resources, and transit. It
encourages access to open space for walking, physical activity,
and time spent outdoors. 10
● Water. Buildings are major users our potable water supply. The
goal of credits addressing water efficiency is to encourage smarter
use of water, inside and out. Water reduction is typically achieved
through more efficient appliances, fixtures, and fitting inside and
water-wise landscaping outside.11
10
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
11
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
20. 19
● Energy. LEED encourages a wide variety of strategies to address
energy consumption, including commissioning; energy use
monitoring; efficient design and construction; efficient appliances,
systems, and lighting; and the use of renewable and clean sources
of energy, generated on-site or off site. 12
● Materials and resources. During both construction and
operations, buildings generate large amount of waste and use
tremendous volumes of materials and resources. These credits
encourage the selection of sustainably grown, harvested, produced
and transported products and materials. They promote the
reduction of waste as well as reuse and recycling, and they take
into account the reduction of waste at a product’s source.13
● Indoor environmental quality. The average American spends
about 90% of the day indoors, where pollutant concentrations may
be two to hundred times higher than outdoor levels. Thus indoor air
quality can be significantly worse than outside. LEED credits
promote strategies that can improve indoor air, provide access to
natural daylight and views, and improve acoustics.14
● Awareness and education. A building’s occupants need to
understand what makes their building green and have the tools to
make the most of its features. The LEED for Homes rating system
has a separate category to emphasize the role homebuilders and
real estate professionals play in interpreting these systems and
features for homeowners. In rating systems geared toward
12
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
13
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
14
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
21. 20
commercial buildings, awareness and education are addressed
under innovation.
● Innovation. LEED promotes innovation in design and operations
by offering bonus points for improving a building’s performance well
beyond what is required by the credits or for incorporating green
building ideas that are not specifically addressed elsewhere in the
rating system. This credit category also rewards the inclusion of a
LEED Accredited Professional on the project team. Additionally,
teams may earn credit in this category for an education plan that
shares green building information with occupants and the public.15
● Regional priority. USGBC’s regional councils, chapters, and
affiliates have identified the environmental concerns that are most
important for every region of the country, and six LEED credits that
address those local priorities have been selected for each region. A
project team that earns a regional priority credit earns one bonus
point in addition to any points awarded for that credit. Up to four
extra points can be earned in this way.
LEED for Neighborhood Development diverges significantly from other
rating systems and is organized around three main categories, focusing
on where, what, and how to build green at a community scale. 16
● Smart location and linkages. This section of the rating systems
provides guidance on where the project is built, encouraging the
selection of sites with existing services and transit.
● Neighborhood pattern and design. Neighborhoods should be
compact, complete, connected, and convivial. The intent of credits
15
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
16
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
22. 21
in this category is to create environments that are walkable, vibrant
with the mixed-use establishments, and connected to the larger
community.
● Green infrastructure and buildings. This category focuses on
measures that can reduce the environmental harms associated
with the construction and the operation of buildings and
infrastructure within neighborhoods, with a goal of not just reducing
the environmental consequences, but also enhancing the natural
environment.
Additionally, LEED emphasizes the critical role of the integrated process
and ongoing performance monitoring across all phases and projects
types.
LEED rating systems generally have 100 base points plus six Innovation
points and four Regional Priority points, for a total of 110 points. The
level of certification for commercial projects is determined according to
the following scale (Fig.5) :
- Certified, 40-49 points
- Silver, 50-59 points
- Gold, 60-79 points
- Platinum, 80+ points
LEED for Homes certification levels vary slightly because the rating
system is based on a 125-point scale, plus 11 innovation points.17
17
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
23. 22
Figure 5. Range of LEED certifications 2016.
Energy and Atmosphere
ENERGY STAR portfolio Manager is an interactive online management
tool set up by EPA and part of the ENERGY STAR program. (Fig.6)18
It supports tracking and assessment of energy and water consumption.
In portfolio Manager a score of 50 represents average building
performance. The design and operation of buildings, neighborhoods, and
communities can dramatically incentive energy efficiency and benefits
from cleaner, renewable energy supplies.
Following an integrated process helps identify synergistic strategies for
the following areas:
● Energy demand
● Energy efficiency
● Renewable energy
● Ongoing performance
18
Energy Star Government, https://www.energystar.gov/
24. 23
Energy demand
Saving energy begins with reducing energy demand, conservation.
Green buildings can reduce demand for energy by capturing natural,
incident energy such as sunlight, wind and geothermal potential, to
reduce loads. For example:
● Community planning can support building configurations that
minimize solar gain in summer and maximize in the winter
● Adjacent buildings can be designed to shade and insulate each
other
● Building designs that incorporate passive strategies, like daylight,
thermal mass, and natural ventilation, reduce the demand for
artificial lighting, heating and cooling
● Technologies and processes can be used to help occupants
understand their patterns of energy consumption and reduce both
individual and aggregate energy demand
Figure 6. Home performance with ENERGY STAR programs, October 2010.
25. 24
In addition to reducing demand, green building encourages sustainable
methods for meeting energy needs. This may be more applicable when
addressing a project’s use of refrigerants, substances used in cooling of
systems. Refrigerants were widely employed throughout the 20th century
for transferring thermal energy in air-conditioning and refrigeration
systems. Although these substances have remarkable functional
properties, they also have damaging side effects for the environment. In
the 1980’s, research emerged demonstrating that certain refrigerant for
buildings systems were depleting stratospheric ozone, a gas that protects
humans and the environment by absorbing harmful UV radiation, and
contributing to climate change. The Montreal Protocol subsequently
banned the production of chlorofluorocarbon (CFC) refrigerant and is
phasing out hydro chlorofluorocarbon (HCFC) refrigerant, both organic
chemical compounds known to have ozone-depleting potential. To
achieve LEED certification, new buildings may not use CFC-based
refrigerant, and existing buildings must complete a total CFC phase-out
prior to project completion. LEED award points for projects that entirely
avoid the use of refrigerant or select refrigerants that balance concerns of
ozone depletion and climate change. LEED recognizes that although
there are no perfect refrigerants, it is possible to carefully consider
performance characteristics and environmental effects and select a
refrigerant with an acceptable trade-off.19
19
LEED 2009 New Constructions & Major Renovations – U.S. Green Building Council, 2009
26. 25
Strategies for reducing energy demand in design and planning:
● Establish design and energy goals. Set targets and establish
performance indicators at the outset of a project and periodically
verify their achievements.
● Size the building appropriately. A facility that is larger than
necessary to serve its function creates costly and wasteful energy
demand.
● Use free energy. Orient the facility to benefit from natural
ventilation, solar energy and daylight.
● Insulate. Design the building envelope to insulate efficiently against
heating and cooling losses.
Strategies for reducing energy demand in operations and
maintenance:
● Use free energy. Use the facility’s orientation and appropriate
shades, windows and vents to take advantage of natural
ventilation, solar energy, and daylight.
● Monitor consumption. Use energy monitoring and feedback
systems to encourage occupants to reduce energy demand. 20
Energy efficiency
Once demand reduction strategies have been addressed and
incorporated, the project team can begin to employ strategies to promote
energy efficiency, using less energy to accomplish the same amount of
work. Getting the most work per unit of energy is often described as a
20
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
27. 26
measure of energy intensity. Common metrics for buildings and
neighborhoods include energy use per square foot and use per capita.
Through the integrated process, green building project teams can identify
opportunities from employing synergistic strategies. For example, by
improving the building envelope, the space between interior and exterior
environments of a building, which typically includes windows, walls, and
roof, teams may be able to reduce the size of HVAC systems or even
eliminate them altogether. This kind of integrated design can reduce both
initial capital costs and long-term operating costs.
Strategies for achieving energy efficiency21
● Address the envelope. Use the regionally appropriate amount of
insulation in the walls and roof and install high-performance glazing
to minimize unwanted heat gain loss. Make sure that the building is
properly weatherized.
● Install high-performance mechanical systems and appliances.
Apply life cycle assessment to the trade-offs between capital and
operating costs, and evaluate investments in energy efficiency
technologies. Appliances that meet or exceed ENERGY STAR
requirements will reduce plug load demands.
● Use high-efficiency infrastructure. Efficient street lighting and LED
traffic signals will reduce energy demands from neighborhood
infrastructure.
● Capture efficiencies of scale. Design district heating and cooling
systems in which multiple buildings are part of a single loop.
21
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
28. 27
● Use energy simulation. Computer modeling can identify and
prioritize energy efficiency opportunities.
● Monitor and verify performance. Ensure that the building systems
are functioning as designed and support the owner’s project
requirements through control systems, a building automation
system, and commissioning and retro commissioning.22
Renewable energy
Reduced demand and increased efficiency often make it cost-effective to
meet most or all of building’s energy needs from renewable sources. So-
called green power is typically understood to include solar, wind, wave,
biomass, and geothermal power, plus certain forms of hydropower.
(Fig.7)
Figure 7. U.S. Energy Information Administration - Renewable electricity generation by fuel
type in the Annual Energy Outlook 2015 reference case, 2000-2040; in trillion kilowatts.
22
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
29. 28
Use of these energy sources avoids the myriad of environmental impacts
associated with the production and consumption of nonrenewable fuels,
such as coal, nuclear power, oil, and natural gases.
LEED distinguishes between on-site renewable energy production and
purchase of off-site green power. On-site energy production typically
involves a system that generates clean electricity, such as solar
photovoltaic panels that convert the sun's energy into electricity. Off-site
renewable energy is typically purchased at a premium price per kilowatt-
hour from a utility or a provider of renewable energy certificates (RECs).
RECs represent a tradable non tangible commodity associated with the
qualities of renewable electricity generation. RECs, and their associated
attributes and benefits, can be sold separate from the underlying physical
electricity associated with the renewable-based generation source.
Strategies for meeting energy demand with renewable energy
● Generate on-site renewable energy. Install photovoltaic cells, solar
hot water heaters, or building-mounted wind turbines.
● Purchase off-site renewable energy. Buy green power or renewable
energy certificates to reduce the environmental impact of
purchased electricity and promote renewable energy generation.
Ongoing energy performance
Attention to energy use does not end with the design and construction of
an energy-efficient building. It is critical to ensure that the project
functions as designed and that it sustains and improves this performance
over time. Design flaws, construction defects, can undermine
performance goals, set during planning and design, equipment
30. 29
malfunctions, and deferred maintenance. Monitoring and verification
provide the basis for tracking energy performance, with the goal of
identifying and resolving any problems that may arise. Monitoring often
involves comparing building performance measurements with predictions
from a calibrated energy simulation or industry benchmarking tool. EPA’s
ENERGY STAR Portfolio Manager is one of the most widely used
benchmarking systems. Users enter data on electricity and natural gas
consumption, along with other supporting information, into a Web-based
tool. The system then evaluates the performance of the building against
that of others with similar characteristics. This is an exceptionally useful,
free tool for gauging performance of buildings.
Commissioning is a systematic investigation by skilled professionals who
compare building performance with performance goals, design
specifications, and most importantly the owner’s requirements. This
process begins early in design, with the specification of requirements.
The requirements are considered throughout the building design and
construction process and become the baseline for evaluation. Ongoing
commissioning for building operations ensures that the building continues
to meet its fundamental operational requirements. Retro commissioning
is the same process applied to existing buildings, it is intended to keep a
building on track for meeting or exceeding the original operational goals.
The cost of consuming is often repaid with recovered energy
performance.
31. 30
Strategies for incorporating ongoing performance measurements
into a project 23
● Adhere to the owner’s project requirements. Prepare detailed
owner’s project requirements at the beginning of the design
process and conduct commissioning throughout the life cycle of the
project to ensure that the building functions as designed.
● Provide staff training. Knowledge and training empower facilities
managers to maintain and improve the performance of buildings.
● Create incentives for occupants and tenants. Involve building
occupants in energy efficiency strategies. Promote the use of
energy-efficient computers and equipment, bill tenants from
submeter readings to encourage energy conservation, educate
occupants about shutting down computers and turning out lights
before they leave, and give them regular feedback on energy
performance.
Material and resources
Materials and resources are the foundation of the buildings in which we
live and work, as well as that with which we fill them, the infrastructure
that carries people to and from these buildings, and the activities that
take place within them. The ubiquitous nature of materials and resources
makes it easy to overlook the history and costs associated with
production, transportation, consumption, and disposal. Setting goals for
using sustainable materials and resources is an important step of the
green building process. “Reduce, reuse, recycle” may seem like a critical
component of this work: clearly reducing consumption is critical, and
23
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
32. 31
reusing and recycling waste are important strategies. But green building
requires rethinking the selection of materials as well. Ideally the materials
and resources used for buildings not only do less harm but go further and
regenerate the natural and social environments from which they
originate. To evaluate the best options and weigh the tradeoffs
associated with a selection, teams must think beyond a project’s physical
and temporal boundaries. Life cycle assessment can help a team make
informed, defensible decisions. (Fig.8)
Figure 8. United States Environmental Protection Agency -How waste management impacts
greenhouse gas emissions.
Plentiful opportunities exist to reduce the harms associated with
materials. Using less, finding materials with environmentally preferable
attributes, using locally harvested materials, and eliminating waste
provide a great starting place. A systems-based, life cycle perspective
and an integrative process will help projects achieve their goals
33. 32
addressing materials and resource use. LEED addresses the following
issues related to materials and resources:
● Conservation of materials
● Environmentally preferable materials
● Waste management and reduction
Conservation of materials
A building generates a large amount of waste throughout its life cycle.
Meaningful waste reduction begins with eliminating the need for materials
during the planning and design phase.
Strategies for conserving materials throughout a project’s life
cycle24
● Reuse existing building and salvaged materials. Selecting
resources that have already been harvested and manufactured
results in material savings.
● Plan for smaller, more compact communities. Reduce the need for
new roads and other infrastructures by preventing sprawling land-
use patterns.
● Design smaller, more flexible homes and buildings. Use space-
efficient strategies, reduce unused space such as hallways, and
provide flexible spaces that can serve multiple functions.
● Use efficient framing techniques. Two framing approaches that by
design use less material than conventional framing without
compromising performance are advanced framing, in which studs
24
Guide to the LEED Green Associate Exam, Michelle Cottrell, 2011
34. 33
are spaced 24 instead of 16 inches on center, and structural
insulated panels, which combine framing and insulation into one
rigid component.
● Promote source reduction in operations. Designate office supply
reuse centers or areas that make unused or reusable supplies
available for reuse. Encourage paper conservation through double-
sided and electronic printing.
Environmentally preferable materials25
Materials attributes can be the basis for calling a product green, and
these can occur in any phase of its life cycle. Commonly, products are
designated as environmentally preferable materials because they are:
● Locally harvested or extracted and manufactured
● Sustainably or organically grown and harvested
● Made from rapidly renewable materials, those that can naturally be
replenished in a short period of time (for LEED, within 10 years)
● Contain recycled content
● Made by biodegradable or compostable material
● Free of toxins
● long lasting, durable, and reusable
● Made in factories that support human health and workers rights
For consumers the biggest challenge is identifying what products are
truly green. As public interest in sustainability has grown, so has the
practice of greenwashing, or presenting misinformation to the consumer
25
Guide to the LEED Green Associate Exam - Michelle Cottrell, U.S. Green Building Council,
2011
35. 34
to portray a product or policy as being more environmentally friendly than
it actually is.
Strategies to promote sustainable purchasing during design and
operations 26
● Identify local sources of environmentally preferable products. Using
local materials not only reduces the environmental harms
associated with transportation, it also supports the local economy.
● Develop a sustainable materials policy. Outline the goals,
threshold, and producers for procurement of ongoing consumables
and durable goods. Incorporate systems thinking. Evaluate
materials based on their upstream and downstream consequences.
Monitor compliance to ensure that the policy is effective.
● Specify green materials and equipment. Give preference to rapidly
renewable materials, regional materials, salvaged materials, and
those with recycled content. Choose vendors who promote source
reduction through reusable or minimal packaging of products. Look
for third-party certifications, such as the Forest Stewardship
Council, Green Seal, and ENERGY STAR.
● Specify green custodial products. Choose sustainable cleaning
products and materials that meet Green Seal, Environmental
Choice, or EPA standards to protect indoor environmental quality
and reduce environmental damage.
26
Guide to the LEED Green Associate Exam - Michelle Cottrell, U.S. Green Building Council,
2011
36. 35
Waste management
Building construction generates large amounts of solid waste, and waste
is generated across the building life cycle as new products arrive and
used materials are discarded. This waste may be transported to landfills,
incinerated, recycled, or composted. (Fig.9) Solid waste disposal
contributes directly to greenhouse gas emissions through transportation
and, perhaps more significantly, the production of methane in landfills.
Incineration of waste produces carbon dioxide as a byproduct. EPA has
estimated greenhouse gas emission from building waste streams and
finds that the United States currently recycles approximately 32% of its
solid waste, the carbon dioxide equivalent of removing almost 40 million
cars from the road. improving recycling rates to just 35% could result in
savings equivalent to more than 5 million metric tons of carbon dioxide.
(U.S. Environmental Protection Agency, Measuring Greenhouse Gas
Emissions from Waste (2010)). 27
Figure 9. United States Environmental Impact Agency - Municipal Solid Waste Generation in
the United States in 2012.
27
EPA United States Environmental Protection Agency,
http://www2.epa.gov/greenerproducts
37. 36
The intent of LEED credits in this category is to reduce the waste that is
hauled to and disposed of in landfills or incineration facilities. During
construction or renovation, materials should be recycled or reused
whenever possible. During the building’s daily operations, recycling,
reuse and reduction programs can curb the amount of material destined
for local landfills. 28
Strategies to reduce waste during construction29
● Develop a construction waste management policy. Outline
procedures and goals for construction waste diversion. This policy
should specify a target diversion rate for the general contractor.
● Establish a tracking system. Ensure that the general contractor
provides waste hauler reports and captures the full scope of the
waste produced. Designate a construction and demolition waste
recycling area. Diligent monitoring will ensure that the policy is
effective.
Strategies to reduce waste during operations and maintenance30
● Develop a solid waste management policy. Outline procedures and
goals for solid waste diversion. This policy should specify a target
diversion rate for the facility.
28
Guide to the LEED Green Associate Exam - Michelle Cottrell, U.S. Green Building Council,
2011
29
Guide to the LEED Green Associate Exam - Michelle Cottrell, U.S. Green Building Council,
2011
30
Guide to the LEED Green Associate Exam - Michelle Cottrell, U.S. Green Building Council,
2011
38. 37
● Conduct a waste stream audit. Establish baseline performance for
the facility and identify opportunities for increased recycling,
education, and waste diversion.
● Maintain a recycling program. Provide occupants with easily
accessible collectors for recyclables. Label all collectors and list
allowable materials. Through signage or meetings, educate
occupants about the importance of recycling and reducing waste.
● Monitor, track, and report. Use hauler reports or other reliable data
to monitor and track the effectiveness of the policy. Track
performance goals and provide feedback to the occupants.
● Compost. Institute an on-site composting program to turn
landscaping debris into mulch. Work with the waste hauler to allow
for collection and composting of food and other organic materials.
● Provide recycling for durable goods. Institute an annual durable
goods drive where e-waste and furniture are collected on site and
disposed of properly through donation, reuse, or recycling. Allow
occupants to bring e-waste and furniture from home.
6. LEED guide
6.1 Prerequisites, credits and credit weights
Above all the LEED categories (Fig. 10) , the ones taken into exam and
their corresponding standard prerequisites are:
39. 38
- Energy & Atmosphere: Fundamental commissioning of building
energy systems, Minimum energy performance, fundamental
refrigerant management31
- Materials & Resources: Storage and collection of recyclables32
Figure 10. LEED certification score breakdown.
31
LEED 2009 New Constructions & Major Renovations – U.S. Green Building Council, 2009
32
LEED 2009 New Constructions & Major Renovations – U.S. Green Building Council, 2009
40. 39
The components of prerequisites and credits are:
● Credit name and point value
● Intent - describes the main goal or benefit for each credit or
prerequisite
● Requirements - details the elements to fulfill the prerequisite or
credit. Some credits have a selection of options to choose from to
earn points.
● Benefits and issues to consider - discusses the triple bottom line
values to the credit or prerequisites
● Related credits - indicates the trade-offs and synergies of credits
and prerequisites.
● Reference standards - lists the standards referenced to establish
the requirements of the credit or prerequisites.
● Implementation - suggests strategies and technologies to comply
with the requirements of the credit or prerequisite
● Timeline and team - outlines which team member is typically
responsible for the credit and when the effort should be addressed
● Calculations - although most calculations are completed online, this
section describes the formulas to be used specific to the credit or
the prerequisite
● Documentation guidelines - describes the necessary
documentation requirements to be submitted electronically for
certification review
● Examples - demonstrates examples to satisfy requirements
● Exemplary performance - think of these as bonus points for
achieving the next incremental level of performance
41. 40
● Regional variation - speaks to issues as related to project’s
geographic location
● Operations and maintenance considerations - describes relevance
of the credit or prerequisite after building is occupied, specific to the
EBOM rating system
● Resources - provides other tools or suggestions for more
information on the topic
● Definitions - provides clarification for general and unique terms
presented
Credit weight
Since prerequisites are required, they are not worth any points. All
credits, however, are worth a minimum of one point. Credits are always
positive whole numbers, never fractures or negative values. All credits
and prerequisites are tallied on scorecards (Fig.11) (also referred to as
checklists) specific to each rating system. Any project seeking for
certification must earn a minimum of 40 points, but this does not mean 40
credits must be awarded as well, because different credits are weighted
differently and not worth only one point. To determine each credit’s
weight, USGBC referred to the U.S. Environmental Protection Agency’s
13 Tools for the reduction and Assessment of Chemical and Other
Environmental climate change, resource depletion, human health criteria,
and water intake.33
33
LEED 2009 New Constructions & Major Renovations – U.S. Green Building Council, 2009
42. 41
Figure 11. Example of LEED scorecard for New Constructions and Renovations.
Once the categories of impact were determined and prioritized, USGBC
referred to the National Institute of Standards and Technology (NIST) for
their research to determine a value for each of the credits by comparing
each of the strategies to mitigate each of the impacts.
As a result of the credit weighting and carbon overplay exercise, LEED
values those strategies that reduce the impacts on climate change and
those with the greatest benefit for indoor environmental quality, focusing
on energy efficiency and carbon dioxide (CO2) reduction strategies. For
example transportation is a very important element within LEED, and
therefore any credits associated with getting to and from the project site
are weighted more. Water is an invaluable natural resource, and
43. 42
therefore water efficiency and consumption reduction is weighted
appropriately to encourage project teams to design accordingly to use
fuels, and therefore is also suitably weighted.
6.2 Energy and Atmosphere
Using fossil fuels to generate electricity determines a great environmental
impact. Each step of the electricity production process harms the
environment and ecosystem in one way or another. The burning of coal
produces harmful pollutants and greenhouse gasses that contribute to
global warming and climate change, reducing air quality on a global
scale.
Conventionally designed and built facilities account for 39% of primary
energy use, 72% of electricity consumption, and 38% of carbon dioxide
(CO2) emissions, according to the US Green Building Council
(USGBC).34
Therefore, the LEED rating systems put the most emphasis
on the EA category by offering the largest opportunity to earn points, as
an attempt to reduce the electrical consumption and corresponding CO2
emissions of certified buildings. The EA category includes three
prerequisites to set the minimum performance requirements to be
achieved, thereby requiring any projects seeking certification to reduce
demand at a minimum level. Beginning with an understanding of the
requirements of these three prerequisites helps to comprehend the
concepts of the EA category. These prerequisites are as follows:
- Fundamental Commissioning of Building Energy Systems
- Minimum Energy Performance
34
The U.S. Green Building Council, http://www.usgbc.org/
44. 43
- Fundamental Refrigerant Management
6.2.1. Minimum energy and performance
Perform minimum energy standard, reduce the amount of energy used.
LEED refers to ASHRAE standard 90.1-2007 (Fig.12) to determine the
minimum energy performance requirements for a building seeking LEED
certification. 35
An integrative design process is essential for the EA category, energy
performance, demands, and requirements are affected by multiple
components including:
- Site conditions, such as heat island reduction, can reduce energy
demand as equipment will not need to compensate for heat gain
from surrounding and adjacent areas.
- Building orientation can affect the amount of energy needed for
artificial heating, cooling and lighting
35
LEED 2009 New Constructions & Major Renovations – U.S. Green Building Council, 2009
45. 44
Figure 12. ASHRAE Standard 90.1 – 2007 cover.
Finally, color schemes of interior spaces should also be considered when
designing lighting plans. Lightly colored walls, workstations, and other
interior design decisions to stretch the efficiencies of light even further to
possibly reduce the amount of required fixtures or lamps. The Green
Building and LEED Core Concepts Guide describes the following nine
strategies to use energy more efficiently:
1. Identify passive design opportunities. Take advantage of earth-
supplied elements such as daylighting (ex. appropriate shading and
46. 45
with light shelves and window glazing) and natural ventilation. Be
mindful of orientation, building materials, and building envelope
elements, such as window placement.36
2. Address the envelope. Remember to incorporate high-
performance glazing to avoid unwanted heat gain or loss, properly
insulate the exterior walls and roof, and weatherize the building.
(ex. selecting insulated concrete forms (ICFs) as building envelope
materials increase the energy performance of a building)37
3. Install high-performance mechanical systems. Determine the
trade-offs of the up-front costs versus the operating costs by
conducting a life-cycle cost analysis. (ex. incorporating cooling
towers can help remove process waste heat by the means of water
evaporation, utilizing a heat exchange system can help to reduce
energy demands and save an owner operating costs)38
4. Specify high-efficiency equipment and appliances. Think
ENERGY STAR for office equipment and appliances to reduce
plug-load demands (ex. ENERGY STAR hot water heaters ensure
efficiency).39
5. Use high-efficient infrastructure for street lighting and traffic
signals. Think about the consistent and long-term use of these
fixtures to understand the value of longer life and cost savings from
less energy required for operation. ( installing light-emitting diode
(LED) can help decrease the energy demand for neighborhoods)
36
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
37
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
38
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
39
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
47. 46
6. Capture efficiencies of scale. Think about large universities or
corporate campuses that use district systems to thermally condition
multiple buildings on a single loop.
7. Use thermal energy storage. Refuse heat at night to provide
cooling during the day in the summer and capture heat during the
day to use at night in the winter. 40
8. Use energy simulation. Model the whole building with regulated
energy uses to optimize synergies (Energy modeling tools, such as
eQUEST, assist project teams to determine energy
consumptions).41
9. Monitor and verify performance. Commissioning, implementing
building automation systems, and retro-commissioning all help to
ensure energy efficiency.42
6.2.2. Renewable energy
Keeping with the same goals previously discussed, implementing
renewable energy technologies into a green building project can reduce
the need to produce and consume coal, nuclear power, oil and natural
gases for energy, therefore reducing pollutants and emissions, as well as
increasing air quality. For the purposes of LEED, eligible renewable
energy sources include solar, wind, wave, biomass, geothermal power
and low-impact hydropower. The Green Building and LEED Core
Concepts Guide describes the following two strategies to incorporate
renewable energy and reduce the use of fossil fuels:
40
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
41
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
42
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
48. 47
1. Generate on-site renewable energy. Clean electricity must be
generated on site by photovoltaic panels, wind turbines,
geothermal, biomass, or low-impact hydropower. Think solar water
heaters. 43
2. Purchase green power or renewable energy credits (RECs).
Generated off site and not associated with supplying power to a
specific project site seeking LEED certification. Think tradable
commodities.44
6.2.3. Ongoing energy performance
The benefits of commissioning new buildings and retro-commissioning
existing buildings include monitoring building system demands during
operations. Tracking the performance of a green building ensures that
the building operates as it was designed and intended. The Green
Building and LEED Core Concepts Guide describes the following four
strategies to ensure optimal performance:
1. Adhere to the OPR. Remember, this is the first part of the
commissioning process that takes place as early as possible in the
design process. This helps to communicate the environmental
goals of the project to the design team, to be incorporated into the
drawings and specifications.45
2. Provide staff training. The building occupants should be aware of
how to use less energy, such as turning off lights and computers
after hours. Operations & maintenance staff should also be aware
43
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
44
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
45
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
49. 48
how to operate their facility and the way it was designed to
function.46
3. Conduct preventive maintenance. It typically costs less to be
proactive than reactive. Scheduled maintenance keeps the building
and its systems operating efficiently.47
4. Create incentives for occupants and tenants. Provide feedback
to occupants on energy usage to achieve and exceed the project’s
goals.48
6.3. Materials and Resources
How to properly select materials and what to do with them after their
useful life, two critical elements for the environment and the building
industry, as buildings are a large consumer of natural resources. More
specifically a sustainability guide by San Mateo County suggests
“construction in the United States consumes 25% of all wood that is
harvested, 40% of all raw stone, gravel and sand.” As a result, green
building project team members are advised to evaluate the
environmental impact of their materials and product specifications.
Project teams may then find themselves asking, “Where does the steel
come from? What kind of materials are used to make green building
products? How far is the manufacturing plant from the project site? What
happens to the leftover gypsum wallboard scraps?” To help answer these
questions we need to address two components for consideration as
related to material and resource selection and disposal:
46
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
47
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
48
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
50. 49
1. The life-cycle impacts of building materials
2. Waste management during construction and operation
6.3.1. Conducting life-cycle assessment of building materials to
determine selection
Implementing sustainable buildings materials impact a project’s triple
bottom line, just as with site selection and energy and water demands.
Project teams should perform life-cycle assessments (LCAs) of building
materials, prior to specification, to evaluate the “cradle-to-grave” cycle of
each material, especially as related to the environmental components of
the pollution and the demand of natural resources. The cradle-to-grave
cycle includes the extraction location of raw materials, the manufacturing
process and location, the impact on construction workers and building
occupants, the expectancy term of impact on construction workers and
building occupants, the expectancy term of use during operations, and
the disposal options available. With the evaluation of these components,
the results of an LCA will help to determine the material selections to
include in the construction purchasing policy to help guide the contractor.
Although it may not be feasible to conduct a full LCA for every product,
project teams can refer to the LEED reference guides for material
selection assistance.49
The LEED rating systems suggest for project
teams to implement products with one or more of the following
characteristics, listed as follows:
- Materials with recycled content - avoid landfills and incineration,
reduces the need for virgin raw materials. (Ex. masonry, concrete,
49
National Renewable Energy Laboratory, http://www.nrel.gov/lci/
51. 50
carpet, acoustic ceiling tile,tile, rubber flooring, insulation and
gypsum wallboard)50
- Local/regional materials - reduces transportation impacts,
preserves local economy. Materials that are obtained within 500
miles of the project site. (permeable pavers made with recycled
materials help recharge groundwater and reduce use of virgin
materials)51
- Rapidly renewable materials - preserves natural resource
materials for future generations, can replace petroleum-based
products. (Ex. Animal or fiber materials that grow or can be raised
in less than 10 years. Bamboo flooring, and plywood, cotton batt
insulation, linoleum flooring, sunflower seed board panels,
wheatboard cabinetry, wool carpeting, cork flooring, bio-based
paints, geotextile fabrics, soy-based insulation and straw bales)
- Certified wood materials - preserves materials for future
generations and habitats and maintains biodiversity 52
. (Fig.13)
Figure 13. Major labels that sell certified wood.
50
National Renewable Energy Laboratory, http://www.nrel.gov/lci/
51
National Renewable Energy Laboratory, http://www.nrel.gov/lci/
52
National Renewable Energy Laboratory, http://www.nrel.gov/lci/
52. 51
Calculating Green Building Products for LEED
The LEED rating systems award points to projects that surpass the
minimum thresholds of green product purchasing and therefore the
products are required to be tracked, measured and calculated to prove
compliance. Materials with recycled content, regional materials, salvaged
materials, and rapidly renewable animal or fiber products are calculated
as percentage of the total material cost for a project. FSC wood products
are calculated as a percentage of the total cost of new wood products
purchased for a specific project. After construction, materials are then
documented and tallied to show compliance to earn points. For example,
should a project purchase 60% of their wood products from a sustainably
managed forest, they would earn one point, as the minimum threshold is
to purchase at least 50% FSC certified wood of total wood purchased. If
only portions of assembled products or materials can contribute to
earning the credit, those portions are calculated as a percentage of
weight of the cost of the assembled item. For example, if only 80% (by
weight) of a carpet system has recycled content, only 80% of the material
cost can contribute toward earning the Recycled Content credit.53
6.3.2. Building materials life-cycle impacts
The LEED rating systems not only help to define the parameters of green
building products, but also help to identify environmentally responsible
procurement strategies during both construction and operations, as the
first strategy to reduce the life-cycle impact of the products used at a
project site. As previously mentioned, architects need to specify materials
53
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
53. 52
appropriately to provide contractors the guidelines for the types of
building material they should purchase and use during construction.
During operations, building owners and facility managers should address
the products they are purchasing by also implementing sustainable
procurement policies. As the LEED for Existing Buildings: Operations and
Maintenance (EBOM) rating system dictates, these policies can address
the goals and thresholds for purchasing ongoing consumables, such as
lamp types, food, cleaning products, and paper products; and durable
goods such as electronics and furniture.
Although LEED EBOM is the only rating system that includes a
sustainable purchasing policy prerequisite, each of the rating systems
offer other opportunities to earn points for projects that implement similar
policies. In addition to sustainable purchasing, projects can also
implement the following strategies to reduce the impacts of materials and
products on the environment:
1. Specify green materials. Ex. sustainable procurement choices,
such as cradle-to-cradle (C2C) certified task chairs composed of
recycled content, specifying C2C certified surfaces made of
recycled content with low to no volatile organic compounds (VOCs)
2. Specify green interiors. Keep VOCs to a minimum. Ex. install CRI
Green Label Plus Program carpet tiles to avoid the contamination
of the indoor air, specifying low-VOC paint.
3. Specify green electronic equipment. ENERGY STAR equipment
and appliances from the EA category. BEES (Building for
Environmental and Economical Sustainability:
www.wbdg.org/tools/bees.php), the construction carbon calculator,
ECOCalculator for assemblies, and EPEAT (Electronic Product
54. 53
Environmental Assesment Tool: www.epeat.net) offer LCAs to help
select equipment that use energy efficiently, are made with
recyclable and recycled materials, and tend to require less
maintenance and are upgradable.54
6.3.3. Waste management
Construction processes and building operations should be addressed to
minimize environmental impacts from disposal and waste. (Fig. 14) In the
United States, building construction and demolition alone account for
40% of the total waste stream, while building operations account for 300
tons of waste per year for a building with 1500 employees. When waste
is collected and hauled form a construction site or an existing facility, it is
typically brought to a landfill or an incineration facility, both of which
contribute to greenhouse gas emissions. Landfills produce and then leak
methane and incineration facilities processes produce carbon dioxide. As
another environmental detriment, think about the potential of landfills to
contaminate groundwater sources. As a result, green building project
teams and facility managers are encouraged to address waste diversion
strategies for new and existing buildings to avoid landfills and incineration
facilities. The EPA estimates a reduction of 5 million metric tons of
carbon dioxide, if recycling efforts were to increase just 3% above the
current 32% rate. To help reach this goal, the LEED rating systems offer
point opportunities or implementing waste management policies during
construction, to divert waste by reuse and recycling strategies.
54
Energy Star Government, https://www.energystar.gov/
55. 54
Figure 14. Hierarchy of sustainable waste management.
Construction waste management plans should address whether waste
will be separated on-site into individuality labeled waste containers or
collected in a commingled fashion in one container and sorted off-site. As
with many of the components addressed within the LEED rating systems,
there are trade-offs to address when deciding between the two options.
Commingled collection reduces the amount of space needed on-site,
while on-site collection may require additional labor to manage the
sorting effort. In either case, land cleaning debris and soil should not be
included in the calculations, but metals, concrete and asphalts should all
be collected for recycling and accounted for. Recycling options for paper,
cardboard, plastics and wood varies by region. Each of the rating
systems includes a prerequisite to address waste management policies
during operations for the collection and storage of recyclables. At a
minimum, LEED projects must recycle paper, corrugated cardboard,
56. 55
glass, plastics and metals.55
LEED EBOM offers point opportunities for
auditing waste streams and implementing waste management policies for
ongoing consumables (such as soap, batteries and paper goods) and
durable goods (such as furniture and electronics).
Strategies to reduce waste56
1. Size the building appropriately. Smaller buildings use less
energy and have lower operations costs.
2. Develop a construction waste management policy. Goals
addressed as a 50% diversion could earn a point by reducing,
reusing or recycling.
3. Encourage recycling. The storage and collection of recyclables is
required for projects seeking LEED certification.
4. Reuse or salvage building materials. Extends useful life of
products and reduces the need for raw materials. Also can save
money as opposed to buying new.
5. Reuse existing buildings instead of tearing down building
new.
6. Compost. Use landscaping and food debris as muc.
7. Consider new technology, design and construction decision.
Consider finishing concrete floor to avoid the need for a floor finish
such as carpet or ceramic tile, or consider specifying carpet tiles in
lieu of roll goods to minimize the amount needed for replacement
should an area get damaged.
55
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
56
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
57. 56
7. Case Study: Peter Kiewit Institute -
University of Omaha Nebraska
7.1 Project overview
The Peter Kiewit Institute is a facility in Omaha, Nebraska that houses
academic programs from both the University of Nebraska-Lincoln's
College of Engineering and the University of Nebraska at Omaha's
College of Information Science and Technology.
Designed and built in 1996 in partnership with the University of
Nebraska–Lincoln, the University of Nebraska at Omaha, and companies
in the private sector.57
The building was conceived in order to leave open further changes and
additions to the original project. The expansion project arises from
important shortcomings and requirements needed more than ever
needed by the increasing numbers of faculty members, staff and
students.
The Institute building was master planned to expand to the south west,
connecting the 2 wings of the existing building that then closes the loop
for a more fluid circulation pattern. This enhances flexibility and
integration of the 2 colleges occupying the building by eliminating any
dead ends. The connection points at the ends, the center enclosure
created by the loop, and the potential new indoor outdoor views can
augment visual evidence to the visitor and the user that this is a high
57
Wikipedia, https://en.wikipedia.org/wiki/Peter_Kiewit_Institute
58. 57
performance environment of innovative research that leverages the
collaborative opportunities between the 2 colleges. To meet the projected
space needs; the buildable area on the site results in a three story
addition. The new spaces are to be designed for adaptability and
flexibility for future research and learning concepts. It should also
incorporate innovative processes for taking the “pulse” of the built
environment to test and monitor effects on building systems and the
human experience. Special attention is necessary to develop social and
collaborative spaces for students and faculty, a vibrant and active place
encouraging students to stay.
The position of the addition builds on a stepping up form, starting with the
existing 1st story offices, to the 2nd story labs and then to the new 3rd
story addition. This is in compliance with the Aksarben Village
development of intentionally scaling up the buildings from low to high
masses along main access ways such as Center Street and Pacific
Street. The expansion can be phased to address needs as they develop.
Containing equal portions of science and nature the building should
make use of rock, water, and natural sunlight, as well as the latest in high
tech infrastructure and amenities.
7.1.1. Request of proposal objectives58
As specified in the RFP (Request of Proposal) the objectives to be
identified will have to be:
58
Request of Proposal for Peter Kiewit Institute expansion, University of Nebraska Omaha,
2014
59. 58
● Building as a Lab – Continuing with the concept of the original
building this will allow:
○ Students to view various building systems
○ Gathering/documentation of data
○ Monitoring of building data for diagnostic and research
purposes
○ Managed manipulation of building systems equipment and
controls
● Support Education with Student focus:
○ Improve Student services – advising and tutoring
○ Provide small group/collaboration spaces Support team
projects
○ Support Capstone Program
○ Provide large classrooms to support large group learning
environments
○ Provide privacy spaces for mentoring and advising
● Increase dedicated research space:
○ Increase per faculty projection in each respective college
○ Flexible /adaptable space
○ All dry lab space (power and data)
○ Modular planning
● Improve Community Outreach:
○ Provide space to support summer camps, seminars, and
workshops
○ Provide large classroom/auditorium space
○ Provide space to support increased STEM activities
60. 59
● Promote Innovation and Entrepreneurship:
○ Create a culture and supportive environment
○ Identify, stimulate and reward creativity
● Promote Integration:
○ Create an environment that promotes and supports
collaborative activities between colleges
○ Allow and promote integration of faculty office assignments to
promote and support collaboration
● Provide Natural Lighting:
○ Allow for as much natural lighting as reasonably possible to
support the teaching, learning, collaboration and research
environment as possible
● Provide Secondary Pacific Street Campus Student Center and
Library Services:
○ Provide facilities to support students that spend most, if not
all their time on the Pacific Street Campus
○ Support PKI, Mammel Hall, Residence Halls and future
growth of Pacific Street Campus
● Improve/Enhance Overall Facility:
○ Provide flexibility to support the breaking down of “silos”
○ Provide flexibility/adaptability
○ Promote collaboration/teamwork
● New Building to be LEED Certified:
61. 60
○ Identify and implement logical cost effective sustainable
opportunities
○ Support “Building as a Lab” concept
○ Support the CoE and IS&T academic programs
7.1.2. Facility requirements
Code Use Quantity Existing SF 5 Year
projection
100 Classroom Facilities 10,758 9025
110 Classroom 160 250 seats
110 Classroom & Seminar Rooms
24-100 seats
115 Classroom Service
1
5
58,669
1
3
6,250
2,475
300
20,150
200 Laboratory Facilities
210 Class Laboratory C.O.E.
210 Class Laboratory I.S.T.
215 Class Laboratory Service
Special Class Laboratory C.O.E.
500
220 Special Class Laboratory I.S.T.
220 Special Class Laboratory
Capstone
225 Special Class Laboratory Service 150
230 Individual Study Laboratory
C.O.E.
230 Individual Study Laboratory I.S.T.
62. 61
235 Individual Study Laboratory
Service
250 Research Laboratory C.O.E.
43 (80) 15 10,500
250 Research Laboratory I.S.T. 46 (74) 10 7,000
255 Research Laboratory Service 2,000
36,103 24100
300 Office Facilities
310 Office Facilities C.O.E. 43 (80) 20 24,00
310 Office Facilities I.S.T. 46 (74) 15 18,00
310 Office Facilities Grad. Assist.
C.O.E.
130
(400) 135 8,100
310 Office Facilities Grad. Assist.
I.S.T.
359
(667) 175 10,500
315 Office Service 400
350 Conference Room 900
355 Conference Room
Service
Code Use Quantity Existing SF 5 Year projection
6,015 7550
400 Study Facilities
63. 62
Reading/Study/Reference/Ro
om (Small Group Study 410
(10 @ 6 8 chairs))
7 1,540
410
Reading/Study/Reference/Room
(Study Cabins)
4 160
410 Reading/Study/Reference/Room
(Video/ Maker)
1 500
430 Open Reading Room (Landing and
Gathering with
Café/Snack)
70 2,100
430 Open Reading Room (Booths and
Tables)
50 1,500
440 Library Support Space (Check out
equip., schedule study rooms) 1 150
455 Study Service (Student use
Display)
400
650 Lounge 2 800
655 lounge Service
680 Meeting Room 2 400
685 meeting Room Service
6,015 3,990
600 General Use Facilities
610 Assembly Multi
Purpose Center for Collaboration
3,000
615 Assembly Service 330
Exhibition
Entrepreneurship, Multi
Discipline 620 Innovations
660
64. 63
625 exhibition Service
650 Lounge Distributed
Library annex
655 lounge Service
680 Meeting Room
685 meeting Room Service
4,349 1,500
700 Support Facilities
Total Net Area
Total Gross Area
121,909
192,380
66315
100,000
7.2. Site survey
The University of Nebraska Omaha is located in midtown Omaha, with a
campus separated in two by Elmwood Park. The campus north of
Elmwood is referred to as 'North Campus' and the campus south of
Elmwood as 'South Campus'. The North Campus is the largest and
primary campus for the University of Nebraska Omaha. The college's
facilities located in this part of campus are the College of Arts and
Sciences; College of Communication, Fine Arts, and Media; College of
Education; College of Public Affairs and Community Service; Graduate
Studies; International Studies; Service-Learning Academy. Additionally,
the North Campus is also the home to the Dr. C.C. and Mabel L. Criss
Library, the Strauss Performing Arts Center, the UNO Art Gallery, and
the Black Box Theater, a state-of-the-art facility with mobile seating units
that allow a customizable and transformative space.
On North Campus are also located part of the dorms buildings such as
University Village and Maverick Village student housing complexes, each
65. 64
composed of multiple buildings, are spread across the western edge of
the North Campus, and additional housing is present on South Campus.
The HPER (Health, Physical Education, and Recreation) building is a
recently renovated complex that houses the Athletic Department for the
Division I Omaha Mavericks as well as student fitness areas. Attached is
the Sapp Field House and Al F. Caniglia Field. The Pep Bowl is located
near Caniglia Field.
The Pacific Campus (formerly South Campus) houses the primary
facilities for the College of Business Administration and the College of
Information Science and Technology, which includes the Peter Kiewit
Institute, the Charles W. Durham School of Architectural Engineering,
and the Firefly supercomputer. The Scott Technology Center incubator,
which aims to assist start-up enterprises, is also located on the Pacific
Campus. The Scott Data Center and Scott Conference Center are other
features of Pacific Campus. A complex of new dorms is also present on
South Campus, Scott Village, and on November 2015 the southern area
of the Pacific Campus boosted its area of students attendance with the
hockey Baxter Arena. The Entire Campus cover an area of 534 acres
(216 ha) of which 78 acres (32 ha) are North Campus and 154 acres (62
ha) South Campus. (Fig. 15)
66. 65
Figure 15. University of Nebraska Omaha Campus, Google Maps, 2016.
The PKI building is placed at a central spot, between the two campuses.
It is surrounded by two main streets at north and east, which are Pacific
St. and 67th St. .These roads have the most intense and high traffic flow,
as they are roads of connection between the two campuses, and used by
students, citizens of the neighboring areas and several shuttle lines
provided by the University. As for the south and west, the building is
surrounded by green areas and parking lots at service for the PKI
institute and Mammel Hall - College of building and administration. (Fig.
16, Fig.17, Fig. 18)
67. 66
Figure 16. Peter Kiewit Institute and designated area for the extension building, Request for
Proposal document, 2015.
Figure 17. Peter Kiewit Institute Front View, Google Maps, 2016.
68. 67
Figure 18. Solar path around Peter Kiewit Institute, Google Maps, 2015
7.3. Materials and resource selection
The main intent when selecting materials and resources is to extend the
lifecycle of existing building stock, conserve resources, retain cultural
resources, reduce waste and reduce environmental impacts of new
buildings as they relate to materials manufacturing and transport.
LEED guide specifies that by maintain the existing building structure
(including structural floor and roof decking) and envelope (the exterior
skin and framing, excluding window assemblies and non-structural
roofing material), credit score is achieved. For this reason, it was chosen
to keep the exterior walls of the existing PKI building and add the new
extension structure on the south-west area.
69. 68
During the construction of the new building it will be necessary to recycle
and salvage nonhazardous construction and demolition debris. Develop
and implement a construction waste management plan that, at a
minimum, identifies the materials to be diverted from disposal and
whether the materials will be sorted on-site or comingled. Excavated soil
and land-clearing debris do not contribute to this credit. Calculations can
be done by weight or volume, but must be consistent throughout.
It will be necessary to establish goals for diversion from
disposal in landfills and incineration facilities and adopt a construction
waste management plan to achieve these goals. Consider recycling
cardboard, metal, brick, mineral fiber panel, concrete, plastic, clean
wood, glass, gypsum wallboard, carpet and insulation. Construction
debris processed into a recycled content commodity that has an open
market value may be applied to the construction waste calculation. A
specific area will be designated on the construction site for segregated or
comingled collection of recyclable materials, and track recycling efforts
throughout the construction process. Identify construction haulers and
recyclers to handle the designated materials. Note that diversion may
include donation of materials to charitable organizations and salvage of
materials on-site.
Some of these materials will be reused on the realization of the new
building, such as bricks, wood, steel.
The materials applied on the new building will incorporate recycled
content materials, thereby reducing impacts resulting from extraction and
processing of virgin materials for at least the maximum percentage
materials recycled for each point threshold, such as 20% for 2 points.
70. 69
All materials and products that are extracted and manufactured within the
region, thereby supporting the use of indigenous resources and reducing
the environmental impacts resulting from transportation within 500 miles
(800 kilometers) radius of the site.59
(Fig.19)
Figure 19. Radius of site for material selection, Google Maps, 2016
All wood-based materials and products must be certified in accordance
with the Forest Stewardship Council’s principles and criteria, for wood
building components and the minimum use will be of 50% (based on
cost). These components include at a minimum, structural framing and
general dimensional framing, flooring, sub-flooring, wood doors and
finishes. 60
Defined these basic guidelines and taking into consideration
the orientation of the building, in anticipation of the subsequent energy
analysis, only the building envelope will be taken into analysis, as
59
Green Building and LEED core concepts - U.S. Green Building Council, 2011.
60
Green Building and LEED core concepts - U.S. Green Building Council, 2011
71. 70
primary mean of energy dispersion. The wall types and insulation levels
are varied as a function of orientation and exposure. (Fig.20, Fig.21)
Figure 20. South Wall, Revit, 2015
1. South walls:
a. drywall / plaster / concrete
b. vapor barrier
c. 2x8 stud walls with sprayed insulation ( cellulose /
cementitious foam insulation)
d. ½” exterior wall sheathing (fiberboard, 85% recycled
material)
e. air barrier
f. air space with vertical furring strip
g. 1x brick / concrete
Figure 21. West Wall, Revit, 2015
2. West wall:
a. drywall / plaster / concrete
b. vapor barrier
c. 1 ½” rigid insulation ( polyisocyanurate (polyiso), expanded
polystyrene (EPS)
d. 2x8 stud walls with sprayed insulation ( cellulose /
cementitious foam insulation)
e. ½” exterior wall sheathing (fiberboard, 85% recycled material)
f. air barrier
g. air space with vertical furring strip
h. brick / concrete
72. 71
While brick and concrete may appear as materials which aren’t strictly
“green” the choice to apply them was made taking into consideration their
durability. These materials have both high levels of embodied energy
from high temperature firing required to manufacture them, but their
overall life cycle analysis is good because of their lasting quality with little
maintenance. Both of them are also available with recycled content.
Floors will be in structural polished concrete, eliminating work and
materials required for an applied surface.
All windows are in double glazing with low E film. Below is the
represented the Revit model.
7.4. Autodesk Revit energy simulation
Energy simulation helps analyzing the movement of energy in, out, and
through the rooms and volumes in a building model. This information can
help designers make better informed, cost-effective decisions that
improve the performance and reduce the environmental impact of
buildings.
Whole building energy simulation measures expected energy use (fuel
and electricity) based on the building's geometry, climate, building type,
envelope properties, and active systems (HVAC & Lighting). It takes into
account the interdependencies of the building as a whole system.
Energy Analysis for Autodesk Revit was used to perform the whole
building energy simulation on the PKI project. This add-in connects the
design power of Revit to the analysis power of Autodesk Green Building
Studio.
73. 72
Green Building Studio is Autodesk's core whole building energy
simulation engine. This flexible cloud-based service uses the DOE2
simulation engine. It allows to run building performance simulations to
optimize energy efficiency and to work toward carbon neutrality earlier in
the design process. Green Building Studio helps extend the ability to
design high performance buildings at a fraction of the time and cost of
conventional methods.
At first a Revit architecture model was first created, secondly the
simulation was performed.
The fastest and most reliable form of simulation is based building
elements such as walls, windows, doors, roofs, curtain panels, ceilings
and all the basic elements that bound space.61
The basic steps followed for the energy simulation were data settings
such as: the application of location and climate data (city or latitude and
longitude of building), building and space type (residential, school, office,
etc..), materials and systems and operation. Once all these parameters
are defined the energy simulation can be run. The defined information is
sent to Green Building Studio server which as result establish overall
energy use and cost and potential energy savings through various kind of
graphics.
Analysis of the results permits to apply proper changes to the model, by
resetting and modifying the data and parameters for a proper
improvement of the building.
The simulation results are illustrated in the graphics below. (Fig.22-32)
61
Autodesk, http://www.autodesk.com/education/home
85. 84
7.5. Heating system selection
As type of HVAC system it was hypothesized the use of ductless mini-
splits. Ductless mini-split systems are easier to install than some other
types of space conditioning systems. For example, the hook-up between
the outdoor and indoor units generally requires only a three-inch hole
through a wall for the conduit. Most manufacturers of this type of system
can provide a variety of lengths of connecting conduits, and, if necessary,
you can locate the outdoor unit as far away as 50 feet from the indoor
evaporator. This makes it possible to cool rooms on the front side of a
house, but locate the compressor in a more advantageous or
inconspicuous place on the outside of the building.
Mini splits have no ducts, so they avoid the energy losses associated
with the ductwork of central forced air systems. Duct losses can account
for more than 30% of energy consumption for space conditioning. In
comparison to other add-on systems, mini splits offer more interior
design flexibility. The indoor air handlers can be suspended from a
ceiling, mounted flush into a drop ceiling, or hung on a wall. Floor-
standing models are also available. Most indoor units are about seven
inches deep and have sleek, high tech-looking jackets. Many also offer a
remote control to make it easier to turn the system on and off when it's
positioned high on a wall or suspended from a ceiling. On the other hand
it does not allow for location of registers for even HVAC distribution and
provides limited air filtration. It may be powered by on-site renewable
electrical generation, in this case solar panels positioned on the roof of
the lecture hall, and fuels. Like conventional air-source heat pumps,
ductless mini-splits move heat from one place to another. In winter, they
