When the
Lady Bird Johnson Middle School opens in Irving, Texas, this August, students will be greeted by more than clean classrooms, empty lockers and freshly mowed athletic fields. They’ll see a dozen 45-foot-tall wind turbines whirring in the breeze, nearly 3,000 solar panels soaking up the sun, and a stock market-like TV display tracking the building’s power usage and energy creation.
Green schools are pretty common these days, but this one goes above and beyond. It will be the first net-zero public school in Texas, the first net-zero middle school in the country and the largest net-zero public school in the country. LEED Gold certification is in the works as well.
Dallas-based
Charter Builders is charged with making the
Irving Independent School District’s bold vision come to life. The contractor went through its first punch list at the end of May and is on track to deliver the $29 million project in time for the 2011 school year. Because the engineering phase took longer than usual, crews have been working six days a week, 10 hours a day, to maintain the 15-month construction schedule.
“This project has a lot of dynamics: LEED Gold plus net-zero plus fast-track,” says Aaron Scates, Charter Builders’ vice president of operations. “We have to be multitasking constantly. We can’t leave any of the goals behind.”
Reduce the Need, Then Meet the Need
With a 40-year history of working predominantly in the K-12 sector, Charter Builders is meeting the challenge head on. The first step was to become educated on the net-zero concept and the nontraditional building components needed to make the 150,000-square-foot building function at such a high level.
To be deemed net-zero, a building must create as much energy as it consumes on an annual basis. The Lady Bird Johnson Middle School will achieve this through a mixture of renewable and efficient energy systems, including 66,000 square feet of rooftop solar panels. The 191-watt
Solyndra solar panels will produce 575 kilowatts of direct current (later transformed into alternating current) power per year.
The photovoltaics generate the bulk of the school’s power, with support from 12 Skystream wind turbines producing 2.4 kilowatts at maximum capacity. Additionally, many of the LEED components—such as high-efficiency glazing, daylight harvesting, and extra insulation on the roof and in the walls—are tied to using less energy, which feeds the net-zero process.
“One can’t be successful without the other,” Scates says. “If you put solar panels on a basic building, you couldn’t install enough to make it worthwhile. First you have to reduce the energy need, then use the solar panels to meet that need.”
The school’s energy consumption will be kept in check with a geothermal HVAC system featuring 105 water-source heat pumps connected to 530 geothermal wells, each 250 feet deep. A 1,800-foot-deep water well, supplemented by rainwater collection and greywater harvesting, provides onsite irrigation.
The Lady Bird Johnson Middle School is expected to consume about half the energy of a typical middle school building. If excess energy is produced, it will be sold to a local electric provider—creating a potential revenue source for the school district. But even more importantly, the school is positioned to serve as a hands-on tool to teach students about geothermal science, rainwater collection, solar panel usage and wind turbine efficiency.
“They want to use it as a teaching environment for the students, the staff, the community and the industry,” Scates says. “The district took a chance on what everybody wants to talk about, but is too scared to do. I commend them.”
Greening OperationsHaving worked with the Irving Independent School District since 2001, Charter Builders wanted to match the owner’s commitment to sustainability on the Lady Bird project.
“Our partner was investing a considerable amount of money in the concept of energy efficiency, so we got together with the subcontractors to ask what we could do to demonstrate that we’re in this with the school district,” says Charter Builders President Charles DeVoe.
The result: Charter Builders instituted a recycling policy, encouraged carpooling, planted local wildflowers and vegetation, and made several changes to its jobsite trailers. Solyndra provided mock-up solar panels that Charter Builders installed to power the jobsite office. The contractor also positioned trailers to capitalize on daylighting, installed low-level lighting and light-control sensors, utilized high-efficiency air-conditioning units and recaptured rainwater from the roof. As a result, the company Charter Builders buys trailers from is changing its processes to deliver more energy-efficient products.
“We didn’t change how we built the project, but we showed an interest in sustainability and doing more than we were asked to do,” DeVoe says. “It was well-received by the district, the community and internally as an organization.”
Tight Budgets, Tight Jobsites
The Lady Bird Johnson Middle School was able to leverage federal funding to help achieve its energy-efficiency goals, but most school districts are pinching pennies when it comes to renovation and construction plans. In the experience of
Skanska USA, Orlando, Fla., area school districts are reserving any funds they have for maintenance projects.
“They’ve gone from proactive assessment criteria to reactive policy. If something happens, they’ll weigh the cost of replacement versus patching it up,” says John Guirges, a project manager with Skanska.
Amid the budget crunch, Skanska has kept busy thanks to the
Orange County Public Schools sales tax initiative, which ends in 2015. About three months ago, the firm wrapped up work on the Winter Park Ninth Grade Center, where at times crews had to perform work less than 20 feet away from students. Working on a tight, occupied campus is always a challenge—something Skanska dealt with when building a 350,000-square-foot replacement for Apopka High School, which opened in April 2010.
“We know the importance of not impacting the learning environment,” Guirges says. “We have to figure out a way to get the big noisy work completed without them knowing we’re onsite.”
Apopka High School is a prototype—an approach some Orlando schools have been taking recently for construction projects that don’t require the integration of existing buildings.
“A prototype ensures a school meets all programmatic needs, including incorporating all of the standards for classrooms. The design is set, but it can be fitted to just about any site and the building materials and type of construction can be changed,” Guirges says.
This approach shortens the design phase significantly, allowing contractors to get down to work more quickly.
Currently, Skanska is putting the finishing touches on the $16.7 million East Wetherbee Elementary School, a 106,000-square-foot prototype designed to replace an overcrowded elementary school. When completed at the end of the month, East Wetherbee will boast 41 classrooms, three labs, art and music rooms, a media center, a cafeteria and a kitchen—plus a 6,000-square-foot outdoor play area.
BIM Implementation
Because Orange County Public Schools worked closely with architects to develop the prototype design, the main challenge on this project was the sitework.
“On most school projects, the district wants to keep stormwater drainage onsite, but because this site was surrounded by wetlands, there wasn’t enough room to keep the drainage onsite. We had to connect overflow to an existing wetland without interfering with the natural setting,” Guirges says.
Having finished most of the sitework—as well as the exterior, roof, windows and doors—crews are busy installing interior drywall partitions, placing lights in the ceiling grid, painting, and performing mechanical, electrical and plumbing fit-outs. Building information modeling (BIM) is being used for MEP coordination—representing one of the first times Skanska has implemented the technology on a school project.
“That process really lends itself to collaboration between us and subcontractors and us and the architect,” Guirges says. “The architect can get instant feedback on conflicts, and we can explain things to the owner better by using BIM.”
In fact, Guirges reports the owner was so impressed that it’s rewriting contracts for architects, engineers and construction managers to incorporate BIM on future projects.
In some ways, George Washington Carver High School in Montgomery, Ala., is like a lot of other education projects: a 224,000-square-foot steel structure built directly behind an existing school in about two years. It features a brick and split-face CMU exterior and a metal roof system—plus classrooms, science labs, a cafeteria, a gymnasium, an athletic facility and an auditorium.
But a few key components set it apart from the typical high school. To start, there are five isolated areas—one in each classroom wing and one in each of the locker rooms—featuring reinforced concrete walls, reinforced roofing and impact-resistant doors that serve as indoor shelters for severe storms. (The school was not affected by the fatal tornados that ripped through the south this spring.)
Other unique aspects of the $39 million school include an indoor shooting range for the ROTC and a culinary arts kitchen.
“I’ve built schools throughout Georgia and Alabama with main kitchens, but this teaching kitchen was a first,” says Ray Harrelson, project manager for
Rabren General Contractors Inc., Auburn, Ala., which completed George Washington Carver High School in March. “I’ve heard it’s one of the best in the state.”
The owner,
Montgomery Public Schools, stepped outside the box on materials selection as well. The district sought an aesthetically pleasing rather than institutional look, which affected wall construction. Most schools have a combination of masonry and drywall veneer in high-traffic areas, like hallways, but George Washington Carver High School features glass curtainwalls, high-impact drywall and metal studs.
“Every school district wants something different,” Harrelson says. “This owner wanted soft flooring to keep costs down, but there’s a lot of maintenance in that. Many other schools would pay costs upfront for tile, but it has less wear and tear.
“We try to give the owners what they want, and I’m very proud of the relationships we were able to build with a new owner and new subcontractors.”