Free Elements in Sustainable Design

The American Public Transportation Association’s (APTA) Sustainability and Public Transportation Workshop in Seattle, Wash., this summer provided transportation professionals with best practices and policies in sustainable public transportation. Speakers discussed examples that highlighted incorporating sustainability into transit system’s planning, construction and operations.

One session included information on the free elements in sustainable design. The project looked at here is the East Valley Operations and Maintenance Facility, a 250-bus facility in Tempe, Ariz. It is owned and operated by the cities of Tempe and Scottsdale and Valley Metro. The facility is on a 23-acre site and has 75,600 square feet of maintenance space, 7,100 square feet of fuel and wash space and 19,650 square feet of administration operations space. Construction of the facility has an anticipated completion date of August 31, 2007.

Ken Anderson, senior associate with RNL provides information about this project. “You have to think comprehensively when you design facilities,” he says, explaining that all of the elements in a design are, in a way, related.

Site Selection
Looking at sites that offer flexibility in building orientation is important. If a site is oddly shaped it may be difficult to squeeze everything in and you aren’t able to orient the buildings in the best possible way.

“Owners and clients and municipalities need to remember to look at sites that are not just based on the size of site they need, but where exactly is that.” Anderson says. Is the location close to employees? With buses coming and going, how far do they have to travel? Anderson mentions, “If you find an ideally sized site but it is 25 miles away from the area that your employees are going to be traveling to do their work, then you’ve got built-in mileage issues.” This “windshield time” can add up from a financial standpoint as well as an environmental one. “There is financial gain to thinking of site selection,” he emphasizes.

Building Orientation In Arizona, the biggest environmental impact the design has to consider is impact from the sun. Most of that impact is on the east and west directions because in the summertime, when the sun is lowest, it shines directly into windows on the east and west side. The ways openings in the building are orientated in relation to the sun are critical.

The administration and maintenance buildings are both oriented linear, east to west, with windows and the glazing on the north and south. “In doing that we can get a lot of natural light into the area but we don’t have to deal with direct sunlight, which translates into heat gain into those offices,” Anderson says. On the maintenance building, the bays open up to the north and the south for the same reason. He explains, “As bay doors are open and workers are working on buses, they don’t have to deal with direct heat gain from sun coming in, or even glare.

“Every environment is different,” Anderson stresses. “In our case, [the sun] was really the driving force that we had to deal with and the result is the way we oriented the buildings down here.”

Window Placement
“Where’s the best view?” is what a lot of people tend to think about first Anderson says. “Think about where you’re placing openings in your walls so that they are most strategically placed in respect to not only the view,” he stresses, but also the environment.

“We tried to place the glazing in a way that it would be conducive to getting good views and getting natural light in the spaces, but also would work well with our particular environmental features,” he says. As for the places where they needed openings where they wouldn’t ideally put them, they would incorporate other features. “We added some elements, some architectural and natural elements like landscaping to try and shade that glass so that we could still have the glass where we needed to,” Anderson says. An architectural element that provides shading around the several areas, including the administration building and over the employee break area is fabric and steel canopies. “The light-colored material helps to reduce what they call the heat island effect,” he says.

Using Local Materials
Anderson states that studies show that upwards of 50 percent of the cost of construction, not the labor, but the cost of the materials used for construction, can be traced back to transportation costs to get the material from the factory to the place of construction. “That’s a significant number,” he stresses. “If a facility is designed with regionally manufactured materials in mind, then you are, by definition, reducing the travel distance.

“One of the things that we have here relatively locally is a pretty large concrete plant,” Anderson says. “We designed the maintenance building and the fuel and wash buildings out of tilt-up concrete panels rather than steel that might have been wrapped with masonry or metal panel.” At the time they were designing it, concrete and steel were running relatively close in costs, but when they added in the fact that they could get the concrete locally, the cost of the product went down. Anderson says regionally manufactured materials not only make building easier, “If it’s done well, that can be a savings to the project.”

Creative Thinking
“I think it’s important for everyone on the team, the design team as well as the client team, to come in to a project with a fresh slate or a blank slate,” Anderson says. One of the difficulties he mentions, is when people come together to work on a project and have the mentality that since it’s always been done a certain way, it needs to continue to be done in that same way. “There is some value to experience, but at the same time, creative thinking right from the beginning is really nothing more than being able, or being willing, to think outside of the box. Being able to analyze and discuss, and possibly implement new ideas that you haven’t done before.”

One of the creative solutions that hadn’t been done before for this particular project was using decomposed granite parking. Anderson says, “As far as I know, in the city of Tempe, they don’t have any other city facilities that have that.

“When we first proposed it and discussed it, there was some resistance from some areas, particularly the folks that would have to maintain it, by saying ‘we’ve never done it that way.’” Once they were able to think about it creatively and thoughtfully, then a lot of the reasons for opposition faded. The decomposed granite reduces heat island effect and run-off.

Creativity went into the landscaping as well. The landscaping is drought-resistant; choosing materials in a hot and arid environment that are resistant to drought and will require less water to survive. Utilizing regional plants make this landscaping more cost effective. Anderson mentions, “You would want to be cognizant of that where ever you are, whether it be in the desert or up in the mountains.”

LEED Certification
The project is going for two LEED certifications. The facility administration office will be submitted for LEED Gold and the remainder of the project will be submitted for LEED Silver. Anderson says, “Right now we are submitting enough points to achieve gold, anticipating that we may not get all those points.” Because of the function of the maintenance facility, there were some limitations on what could be done, mostly with the HVAC and the cooling system.

Though the focus here was on the free elements in design, Anderson stresses that for people looking at doing a building like this, they need to focus on the lifecycle cost-benefits. “To really make a true sustainable building, you may run into, depending on the site, depending on the building, you may run into a few decisions that need to be made where you may pay a little bit of money up front to install something, but that something that gets installed is really going to save you money over the lifecycle of the project. To see some of the lifecycle cost-analysis charts for this project, you can view them here.

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