Tempe Transportation Center is the centerpiece of Tempes award winning transportation program. The 40,300 sf, three-story mixed-use building houses the Citys Transportation Offices, Traffic Management Center, Community Room and Transit Store, as well as Arizonas first bike stationThe Bicycle Cellarwhich provides secure indoor parking for 114 bikes, showers, lockers, bike repair, and bike rentals. Ground floor retail and food service are important elements in transit-oriented developments, providing amenities for transit patrons, downtown residents, employees, Arizona State University students, and visitors to Tempe. The third floor houses for-lease office and Tempes Traffic Management Center.
The project sits on a 2.7-acre site that was once a paved surface parking lot. The Transit Plaza is a strategic hub for METRO light rail, bus local, regional and neighborhood circulator routes and bike transportation, inviting community activity. The building, plaza and METRO light rail platform respond to the unique context and challenges of the site with design that:
minimizes the need for excavation in an archeological sensitive site
orients building components to reduce heat gain
enhances pedestrian access between buses and trains
accommodates high volume pedestrian traffic from ASU
enhances security for the adjacent Police/Courts Facility
provides site grading that supports ADA accessibility
provides safe movement of buses through the site
The Transportation Center is organized to balance efficiency with the best possible work environment. Due to the buildings unique positioning and proportions, the service functions occur within an expressive core that provides a natural buffer on the west elevation. The adjacent open floor plate provides flexible space to accommodate future uses. This relationship of service and served spaces creates efficiencies in circulation, plumbing and mechanical systems.
High performance building envelope: The east elevation utilizes a solar veil, suspended 10 feet from the building face, to shade steel and glazing from morning heat gain. The shades automatically retract during high winds and can be adjusted from the interior by remote control. The west exposure, adjacent to the Police/Courts complex, is primarily without penetrations for security. The use of an A profile block self-shades the masonry wall and provides an interesting design feature appropriate to the climate.
Building Data: The building envelope and integrated systems were modeled and refined to reduce energy consumption by 50 and substantially decrease carbon emissions. The Center uses .055 BTU/sf/year, in comparison to .096 BTU/sf/year for a standard building or 2,201 MM BTU/year in comparison to 3,868.1 BTU/sf/yr. To date, the buildings collected data reflects an annual carbon footprint reduction of 40 tons. Solar panels heat building water and infrastructure is in place for future photovoltaics. Anticipated potable water savings from chiller system alone equals 1,000 gal/day. Building data will be collected to track reduction in potable water use, amount of recycled stormwater and graywater used, performance of energy systems and carbon reduction.
Desert Green Roof: An eco-roof provides the buildings fifth elevation. It serves to stabilize the temperature in the severe summer heat, reducing the energy necessary to cool the building. The roof buffers the noise from overhead air traffic, preserves the roof membrane, and filters and collects rain water. The north and south elevations of the Community Room open to create an elevated gathering space recalling the historic Arizona room common before the use of air conditioning
Water Conservation: A 14,000-gallon stormwater recovery system collects and filters water from the roof, the adjacent Police sallyport, and from routine power-washing of the bus lane and the public plaza. Recycled water feeds drip irrigation to landscape. Waterless urinals and low-flow fixtures are standard; dual flush toilets use graywater from showers and sinks. The entire landscape on the site and roof incorporates low-water use desert trees and plants, efficient water delivery, and inspired design.
Economics: Life-cycle cost analysis supports systems that provide economical return on investment while incorporating environmental and social benefits to the community. Based on computer modeling, the building energy footprint should be reduced by approximately 50, substantially impacting the Citys costs for energy far into the future. Immediate benefits included refunds from the utility approximately 19,000 for the installation of energy efficient equipment. While the typical roof in Arizona is replaced every 20 years, the vegetated roof system is the same product that has been installed and in use in Europe for 50 years without replacement.
The team carefully considered materials and construction methods based on sustainability, waste stream, maintenance, and longevity to produce a building with a 100-year life span. Private offices within the open office plan access natural light through the glass walls of the DIRTT structural partition system. Using recycled/recyclable materials, the system sits on top of the carpet. It can be disassembled and reassembled to accommodate changes in occupancy without demolition and the attendant waste and landfill impacts. The underfloor air supply reduces energy and allows vents to be repositioned by merely exchanging the 2×2 floor panels, while also providing access for electrical and IT wiring.
The project is seeking LEED Platinum certification. The contractor diverted 94 of the typical construction waste from the landfill. Local construction materials: 45 was manufactured locally and 53 of the locally manufactured material was harvested locally. 34 of materials used came from recycled source.
Educational Value: The climate-responsive design and recycled content materials are unveiled to visitors through an educational interactive Green Touchscreen on the public plaza, using diagrams, photos, text and film clips to explain design strategies and construction methods. Within the Transportation Offices are in-wall teaching panels displaying information about the sustainable interior finishes of the building. The desire to inform the community about sustainability led to the first Re-use/ Recycle signage program in the nation, utilizing left over materials, scraps from construction, old bus tires and abandoned bicycle parts to inform as well as direct visitors. The public art collaboration displays recycled glass slag in a gabion wall, lit from within by LED fixtures that provide a variety of colored light displays in the entry courtyard.