CASE STUDY: Making LEED decisions not always easy
ATLAS building on CU-Boulder campus earns first Gold for public buildings in ColoradoApril 2007
Moe Tabrizzi has learned to be a good juggler. As Resource Conservation Officer for the University of Colorado, it was Tabrizzi’s job to shepherd the construction process of the first Gold-rated, LEED-certified public building in Colorado.
The U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) program is the standard-bearer for evaluating the relative green-friendliness of building projects.
Construction on the ATLAS building began in 2004, and it opened in August 2006, just in time for the start of the fall semester. In that short time, Tabrizzi considered myriad options for earning LEED points and kept a sharp eye on the entire construction process to make sure none of those decisions were compromised.
The ATLAS (Alliance for Technology, Learning and Society) building had to match the existing architectural style of the CU-Boulder campus, which has been described as “legacy” Tuscan Vernacular. It also had to house performance and production studios for six disciplines: art, dance, film, journalism, music and theater.
Hosting classes for 6,000 students, the ATLAS building has three floors above ground and two below, for a total of 66,000 square feet.
The majority, or 60%, of the ATLAS construction budget of $31 million came from student fees. Students voted to charge themselves $100 a year for four new buildings, with the stipulation that the buildings were green and as sustainable as possible. The benchmark campus standard was LEED certification, but, “because of the mandate from the students, our commitment was Silver or better,” Tabrizzi said.
Above the basic certification, which requires 26 to 32 points, buildings can attain the status of Silver, which requires 33 to 38 points; or Gold, which requires 39 to 51 points; or Platinum, which requires 52 to 69 points. ATLAS received 43 points.
Some LEED points were easy, others were difficult to achieve, and still others weren’t worth pursuing because of the ATLAS building’s unique design constraints. Tabrizzi said the process of deciding what to pursue was at times challenging. And once the decision was made to pursue certain points, Tabrizzi said the challenge came in the follow-through, especially in the last few weeks of construction. That’s when a contractor might need another gallon of paint and be tempted to buy what he’s always used without checking the building’s requirements for low-VOC paint.
As Tabrizzi describes it, “There are some things you must do, then you add points as you can. You choose your points and judge which ones you can go for.”
Features include water-free urinals, certified wood, and plugs for electric cars
The water-free urinals cost the same as water-using fixtures, but plumbing costs are less, and they use less water. An added cost is the filters that must be replaced periodically.
Tabrizzi looked at using bamboo, a Rapidly Renewable Material (RRM), for walls and benches, which might have given them more LEED points, but he found the bamboo would have cost more because of transportation costs, and its carbon footprint was higher, also because of the long-distance transportation to Colorado. He also found that they would lose points for importing wood from more than 500 miles. So he turned to certified wood from a supplier who used best practices such as replanting the forest and chain of custody (from forest to lumberyard) certification. (See our story on ANSI’s and SFI’s new sustainable forestry accreditation service in this E-News.)
“There are some best practices that the project manager must insist on,” said Tabrizzi. “For example, low VOC paint. There is no longer a premium on this, it’s accessible in all colors, so there’s no reason not to use it. It’s the same with low-VOC epoxy, caulk and carpet. You can also bring in recycled materials.”
And in other instances, Tabrizzi found that “Some points are easy because of the environment and community support.” For instance, Tabrizzi said because of the location of ATLAS the points for ‘access to public transportation’ were easy ones. More points were available to ATLAS because the majority of campus buses run on B20 bio-diesel using cooking oil from the campus cafeteria. And since ATLAS is next to the campus power plant, it was easy to incorporate the use of steam for heating and chilled water for cooling. “And, there are local places to manage (recycle) construction waste, so we could get those points.”
The bottom line of best practices should be a savings in building maintenance and energy use. Tabrizzi points out that the ATLAS building is 30% more energy efficient than recently built similar buildings in Colorado, just one example of the bottom line savings of building green at ATLAS.
So far, in its first six months, the building has performed well. One of the pleasant aspects of being inside a Gold-certified building? “You know that new-building smell?” Tabrizzi asks. “Well, it’s not good for you—everything about that smell is bad. And this building didn’t have that smell. It was good for you from the moment we opened the doors.”
Some of the features of the ATLAS building that helped earn Gold certification
• Insulation: Main door airtight and air-locked; windows high-efficiency, double-paned
• Water conservation: Low flow fixtures, waterless urinals
• Lighting: Energy efficient direct and indirect lighting uses less than 1 watt per square foot; occupancy sensors turn lights off when rooms are not occupied
• Indoor air quality: CO2 sensors bring in conditioned air only when people (gauged by levels of CO2) are in the building. After hours, building goes into sleep mode: lights off, HVAC goes to different mode
• Materials and resources: Carpet tile, so can replace sections, not entire hallway. Certified wood. Low-VOC paint and flooring.
• Built with sandstone mined in Kansas (within 500 miles)
• Mixed concrete used up to 20% recycled ash
• Exceeded LEED requirement for construction waste management. Example: shoring to pour foundation was recycled.
• Landscaping designed to provide a 79% reduction in potable water consumption
Story by Kay Turnbaugh and Carolyn Oakley. Photos by Kay Turnbaugh and Casey A. Cass, University of Colorado.