LEED-EB O&M at the Rose Garden Arena
Architecture firm Ellerbe Becket (now part of AECOM) designed the 1995 Rose Garden building, which is a precast-concrete-framed structure with a skeletal steel roof. The site, located in Portland's Lloyd District just east of the Willamette River, overlooks the Steel Bridge, with a view across the river to downtown Portland.
The Trail Blazers organization is the decision-making authority on building issues and chose to pursue the LEED-EB: O&M certification project. Vulcan Inc., a firm owned by Microsoft cofounder Paul G. Allen, owns both the Rose Garden and the Trail Blazers. AEG Facilities is contracted to operate the Rose Garden, and Ovations is the contracted food and beverage provider.
Rose Garden Arena: LEED-EB Overview
For its LEED-EB: O&M certification, the Rose Garden arena earned 62 points. That's out of the 100 baseline points — plus ten bonus points — possible in the 2009 version of the rating system (LEED v3). (Six bonus points are possible for "Innovation in Operations" and four in "Regional Priority.")
Green Building Services, Inc. (GBS) — a Portland consulting firm that previously managed the nearby Oregon Convention Center's successful bid for certification under the LEED-EB pilot program in 2004, as well as its recertification in 2008 at the Silver level, under LEED-EB v2.0 — also managed the Rose Garden's LEED-EB effort. GBS principal Elaine Aye, IIDA, LEED AP O&M, was the firm's lead consultant on the Rose Garden project.
To achieve certification under LEED-EB, a building and its site need to meet certification criteria based on the building's operational performance over an identified period of time. The minimum performance period for most LEED-EB categories is three months long; for the Rose Garden, this period was defined as July 15 to October 15, 2009. Monitoring for the Energy & Atmosphere category started nine months earlier.
(LEED-EB: O&M is the only track of LEED-EB, so the two abbreviations are used interchangeably here.)
The Trail Blazers organization and Rose Garden facilities team declined a request to make public their LEED-EB: O&M scorecard, but they did provide point totals in the seven general categories under the LEED-EB: O&M 2009 rating system, as noted below.
Rose Garden Arena: Details by Category
Sustainable Sites (SS): 13 points (out of 26 possible)
The 2009 version of LEED-EB: O&M has greatly increased emphasis on SS Credit 4, "Alternative Commuting Transportation." For this credit, up to 15 points are possible, compared to 4 points in the 2008 version of LEED-EB (under which the Christman Building was certified).
The number of points a project receives for this credit depends on the project's demonstrated percentage reduction in conventional commuting trips, calculated relative to a baseline case that assumes all regular occupants commute alone in conventional automobiles. A project would need to demonstrate a 75-percent reduction to earn 15 points.
Based on the percentage of event attendees and staff who arrive and depart using public transit or other alternative travel modes, the Rose Garden achieved a 37.5-percent reduction in conventional commuting trips compared to the baseline, earning 9 points for this credit — constituting about one-seventh of the total points the arena received toward its LEED-EB Gold certification.
The arena's site is ideal for public transit access: it is centrally located in a part of Portland in which the TriMet MAX light-rail system provides free transit. A major transit station adjacent to the Rose Garden site provides connections among multiple bus and light-rail lines.
In addition, about 150 to 200 people arrive by bike for Blazers games, according to Justin Zeulner, an AEG employee who serves as director of sustainability and planning for the Rose Quarter and the Trail Blazers.
The 20,000-seat arena has 2,500 vehicle parking spaces, including a seven-level, 1,000-space garage attached to the arena and a 300-space garage attached to the Trail Blazers office complex.
When the Rose Garden installed additional bicycle racks to encourage cycling, it also added bike tire pumps and improved lighting and security cameras for the bike parking area. Shelters were also added for some (but not all) of the racks to keep the bikes dry in the rainy winters and springs of the Pacific Northwest. Prior to the enhancements, about 25 people per game traveled to Trail Blazers games by bike, according to Zeulner, even though the arena had more than 100 bike parking spaces available. But within two games after the enhancements were completed, the number of fans attending by bike had increased to more than 200, he reports.
Transit passes are funded for all staff, including part-time event staff. And in an effort to reduce conventional motor-vehicle commuting trips a bit further, electric-vehicle charging stations were installed for VIP reserved parking.
Elaine Aye, the GBS principal, points out that buildings such as the Rose Garden, located in or near dense urban centers equipped with transit systems and pedestrian/ bicycle amenities, can more easily achieve LEED credits for alternative transportation than can suburban buildings — which is consistent with LEED 2009's emphasis on carbon-emissions reductions. Aye also notes that the Rose Garden benefits from being located a city that embraces alternative travel modes.
Also in the Sustainable Sites category, an integrated pest management (IPM) program for outdoor pests was instituted, specifying use of "least-toxic chemical pesticides" — something that is required for SS Credit 3, but not explicitly defined in the LEED-EB: O&M requirements. For the Rose Garden's IPM program, GBS developed a protocol that refers to the least-hazardous subset of pesticides on the "Reduced Risk Pesticide List" established by the City of San Francisco's Department of the Environment. The Rose Garden IPM program also mandates minimal use of chemicals, use only in targeted locations and only for targeted species, and use only after providing advance notification, as called for by LEED-EB.
Under SS Credit 7.2, "Heat Island Reduction—Roof," the Rose Garden received the one point available by cleaning the building's white roof and committing to cleaning it again every two years.
Water Efficiency (WE): 5 points (out of 14 possible)
One of the prerequisites for LEED-EB: O&M is demonstrating that potable water use by indoor plumbing fixtures is at or below the levels specified in the 2006 editions of the Uniform Plumbing Code or International Plumbing Code pertaining to fixture and fitting performance.
WE Credit 2, "Additional Indoor Plumbing Fixture and Fitting Efficiency," provides up to 5 points based on the percentage by which a project further reduces the building's indoor potable water use from that baseline. The Rose Garden achieved a level of water usage 17 percent lower than the baseline, earning 2 points under this credit, thanks to plumbing fixture upgrades: aerators were installed in faucets, and toilets and urinals were replaced with low-flow fixtures.
The Rose Garden also received a point for "Cooling Tower Water Management—Chemical Management." The arena's five cooling towers were retrofitted with proprietary water-treatment technology, materials, and a metering system from Water Conservation Technology International, Inc. According to WCTI, its treatment systems allow cooling towers to use water with high levels of total dissolved solids without equipment corrosion and without mineral deposition on the cooling-tower equipment. Justin Zeulner says the system allows the Rose Garden to continue using the same volume of water for longer periods of time — the facilities team only has to flush the system a few times per year. The annual water savings is estimated at 537,000 gallons (about 2 million liters).
Energy and Atmosphere (EA): 17 points (out of 35 possible)
A variety of steps were taken to reduce energy consumption at the Rose Garden. For example, building envelope studies using infrared scans found thresholds on doors that needed replacement, and wall insulation that had been knocked down. Fixing those heat leaks provided considerable energy savings.
A full-building management system was installed to monitor energy consumption in mechanical systems and identify areas for improvement, and building operation plans and sequences of operations were revised accordingly, to match occupancy.
And lights all over the arena were retrofitted with LEDs and motion detection.
In the facility's marshaling and loading-dock area, 175-watt metal-halide lights were replaced light-for-light with 22-watt compact fluorescents with motion sensors. Keeping the same number of lights in the area ultimately turned out to be a mistake, according to Zeulner: the fluorescents cast so much more light that the garage area is far brighter than it had been before, to the point of overkill.
EA Credit 2 is a three-part credit that addresses building commissioning. To receive both points available under EA Credit 2.1, "Existing Building Commissioning—Investigation and Analysis," the Rose Garden team opted for an ASHRAE Level II energy audit rather than actual commissioning.
Energy engineers from GBS undertook the audit — a survey and analysis of the building's major energy-using systems — and identified potential capital improvements to reduce energy use and operating costs. One of the measures they proposed, which was also eligible for financial incentives from Energy Trust of Oregon, was implemented during the LEED-EB performance period: variable frequency drives (VFDs) were installed on the cooling tower fans. That step alone is estimated to reduce annual energy consumption by 255,000 kilowatt-hours (kWh), according to Ted Spear, P.E., LEED AP O&M, a senior technical consultant at GBS.
Since the end of the performance period, VFDs have also been installed in several of the building's other mechanical systems.
The Rose Garden also earned both of the points available under EA Credit 2.2, for implementation of no-cost and low-cost operational improvements, such as minor equipment repairs.
The combination of energy-saving measures taken as part of the LEED-EB: O&M project reduced annual electricity consumption at the Rose Garden by a total of approximately 2 million kWh — from 12 million to 10 million kWh.
EA Credit 1, "Optimize Energy Efficiency Performance," gives up to 18 points based on the building's energy star rating obtained through the U.S. EPA's Energy Star program's Portfolio Manager tool. For building types that are ineligible to receive a rating in this way, a LEED calculator provides an equivalent rating using the same baseline data — the Commercial Building Energy Consumption Survey (CBECS) survey conducted by the U.S. Department of Energy's Energy Information Administration. Using this calculator, the Rose Garden attained a rating of 76, signifying energy-efficiency better than 76 percent of similar buildings nationwide. That score is worth 5 points under EA Credit 1.
In addition, renewable-energy purchase partnerships were established with the regional electric energy provider, Pacific Power, and the regional natural gas provider, NW Natural, to offset 100 percent of the electricity and natural gas consumed at the Rose Garden, earning all 6 points available under EA Credit 4, "On-site and Off-site Renewable Energy." Through a premium paid for these energy sources, the Rose Garden supports wind energy projects and conversion of cow manure into a usable biogas.
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