Sustainability: Higher Education
Today the higher education campus has become a showcase for sustainable thinking. Students and their parents want to know if a prospective college is truly "Green". The campus built environment reflects that institution's attitude and vision concerning sustainability. At HOLT we help our higher education clients create innovative facilities that demonstrate and teach sustainable design and construction practices.
What is sustainability?
Sustainability, from the Latin sustinere (to hold up), is, in its broadest sense, the capacity to endure. In 1987 the Brundtland Commission of the United Nations defined sustainable development as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs." Others have challenged this definition, asking how any development can be sustainable. Many see sustainability as a balance of three overlapping and often competing systems: environment, economy, and society.
At HOLT, we recognize that development is needed to support and advance societal goals, and we endeavor to achieve social, economic, and environmental sustainability in all that we do.
In December 2005 the American Institute of Architects issued its Sustainable Architectural Practice Position Statement:
The profession is confronting the fact that buildings are the largest single contributor to production of greenhouse gases and almost half of the total annual production. As architects, we understand the need to exercise leadership in our role in creating the built environment. Consequently, we believe we must alter our profession's actions and encourage our clients and the entire design and construction industry to join with us to change the course of the planet's future.
Accordingly, HOLT has joined the AIA 2030 Commitment toward realizing a goal of net zero carbon emissions in new buildings and renovations by the year 2030.
What is LEED?
The LEED Green Building Rating System is a voluntary, consensus-based national standard for developing high-performance, sustainable buildings. It provides a vehicle for quantifying and comparatively evaluating the degree to which any project achieves sustainability.
In the current version, LEED 3.0, there are a total of 110 possible points divided among seven categories: Sustainable Sites, Water Efficiency, Energy and Atmosphere, Materials and Resources, Indoor Environmental Quality, Innovation in Design, and Regional Priority. Within the categories there are prerequisites, which must be satisfied, as well as optional points from which to choose. There are four levels in the rating system, with the minimum points required for each indicated in brackets: Certified , Silver , Gold , and Platinum .
What is a LEED AP?
A LEED Accredited Professional is a trained individual who has passed a test administered by the U.S. Green Building Council. Many of the professional staff at HOLT are LEED APs.
What makes a building "Green"?
As noted above, there is a vast array of possible strategies for making a project sustainable, and many levels of sustainability. In general, we at HOLT strive for maximum attainment in energy conservation, resource management, and indoor environmental quality. Actual strategies depend on the type of project, the owner's priorities, and the particulars of the building and the site.
How much more does it cost to build "Green"?
This is a difficult question to answer, because it depends on the baseline standard against which the sustainable project is measured. In higher education, where the norms of construction are set at a fairly high level, the increment to achieve a moderate measure of sustainability can be quite small. Often the life-cycle costs can be capitalized to completely offset any increase at all, particularly when energy conservation is emphasized.
Besides the construction cost increment, there are additional design costs associated with "Green" buildings. Non-standard energy sources, like geothermal or solar, require specialized engineering in addition to the usual systems design. To optimize building envelope and operating systems, digital energy modeling is a necessary part of the design process. Commissioning is a pre- and post-construction engineering process that helps to insure that operational systems perform to their intended levels of efficiency.
If the project is registered to pursue actual certification, there are additional costs for the substantial amount of documentation required. The actual cost will vary with the size of the project, which points are pursued, and the level of certification sought. As a general rule, a range of 0.5 percent to 2.0 percent of construction cost could be anticipated.
Why should my project be "Green"?
The reasons for sustainable design are as varied as the projects themselves. In the broadest sense, the preponderance of scientific thinking supports the concern that an excess of carbon dioxide in the atmosphere is leading to destructive and accelerating climate change. With nearly half of those emissions coming from buildings, it is important for present and future generations that we strive toward carbon-neutral development.
On a smaller scale, energy costs are increasing at rates in excess of inflation, and designing for reduced energy consumption will pay dividends for the life of the building. In some parts of the country the cost of water is experiencing similar increases, and water conservation measures can have economic as well as environmental benefits.
Improved indoor environmental quality is a feature of sustainable design that everyone can enjoy. When indoor air is free of volatile organic compounds and toxins like formaldehyde, people using the building are happier and healthier. When spaces have windows and daylight, studies have shown that learning and productivity improve. And when spaces have localized control of temperature, humidity, and fresh air, inhabitants are more comfortable. All of these improvements make a project more valuable.
A LEED Certification plaque is not necessary for a building to be "Green," but it is a third-party validation that can itself have market value. As a college or university seeks to attract students from a cohort who increasingly are concerned about a sustainable future, campus projects with LEED Certification help to demonstrate the institution's commitment to sustainability.
What would be an example of a LEED certified building for higher education?
The HOLT portfolio contains several buildings for colleges and universities that have obtained, or are registered and striving for, LEED Certification. A particularly interesting example is the Peggy Ryan Williams Center at Ithaca College, which is LEED Platinum certified.
A signatory to the Presidents' Climate Commitment, Ithaca College makes sustainability a core value of the campus. As a minimum, all new buildings must meet a level of LEED Silver, and the campus is one of only two in the nation with two LEED Platinum buildings.
While the Williams Center incorporates dramatic features, like the geothermal HVAC, the daylighting controls, and the storm water harvesting systems, virtually every element of the project was assessed for potential contribution to the overall sustainability goal. Efforts were made to use regionally extracted/harvested and manufactured materials, and materials with high recycled content. Low-emitting materials were used to eliminate or greatly reduce the presence of volatile organic compounds (VOCs), and no products containing added formaldehyde were permitted. At least fifty percent of the wood and wood products used in the project came from sources certified by the Forest Stewardship Council. Waste management practices during construction diverted more than 75 percent of construction waste through recycling and reuse. As part of the indoor air quality management plan, building ductwork and air systems were carefully protected against dust and contamination during construction, and the building underwent a two-week, high-volume flush-out prior to occupancy.
To achieve energy-efficiency goals and ensure a high-performance building envelope, the entire building skin was designed as a rain screen. The sheathed surfaces are covered in a modified bituminous sheet air barrier, over which open-jointed layers of stone and metal panels are applied. All of the roof surfaces that are visible from within the building are either vegetated or covered with pavers. The main roof above the top floor has a white, reflective Energy Star membrane, and drains toward the center where its rainwater is captured and piped to a 12,000-gallon underground tank to be used as flush water for the building's toilet fixtures.
Among the innovative technologies employed in the design was the ground-source heat-pump (geothermal) HVAC system, which uses a closed-circuit network of thirty-six, 500-foot-deep boreholes to temper the water in the building's distributed heat pump system. The individual heat pumps have the added advantages of providing local control, and of reallocating heat as needed within the building. The system can, for example, remove heat from an interior conference room full of people (cooling) and move it to heat pumps along the perimeter which are in heating mode, without ever having to go outside the loop for additional energy. Carbon dioxide sensors monitor room air throughout the building, and provide fresh outside air as needed through a dedicated ventilation unit with heat recovery. The systems consume no fossil fuels, and with the purchase of green power, the building is carbon-neutral.
Daylghting played an important part in the project's overall energy conservation strategy. The long, narrow footprint and east-west axis, with glazing accounting for forty percent of the exterior skin, evolved through maximizing daylight harvesting in the energy model. The long south-facing façade employs exterior sunshades and interior light shelves to control glare and improve daylighting efficiency, while the north side benefits from abundant, glare-free light. Glazing was selected for optimum efficiency, combining high visible light transmittance (70%) with a low solar heat gain factor (0.37) for a superior light-to-solar-gain (LSG) ratio of 1.90. To take maximum advantage of this natural light, all fluorescent fixtures in the building use electronic dimming ballasts controlled by photocell sensors. The artificial lighting reacts in response to the available natural light, maintaining constant levels of illumination throughout the day.
Together, the geothermal and daylighting systems result in energy savings of more than 34 percent when compared to typical construction.