Project Description
FROM AIA NATIONAL:
1: Design and Innovation
This project strives to educate Charlotte on sustainability through experience. Its program is one of thoughtful community integration and resource efficiency. The program facilitates educational galleries that promote possibilities for reuse by showcasing artfully articulated recycled art. The creators of these exhibits are also part of the building’s program. Living on the top floor of the center for sustainability, the resident artists continuously adapt exhibits and interact with visitors. Visitors also experience sustainability through the building itself, as it is shaped by fundamental passive design strategies. Strategies include a central outdoor courtyard that provides natural light for the interior, exterior shading devices that reduce unwanted solar gain and narrow galleries for cross ventilation. To compliment the fundamental design strategies, innovative building systems are integrated into the building. Concentrated into three elements (water, energy and air) the integrated systems are displayed alongside the exhibits, readily available for both functional and educational purposes. Water systems include water collection, purification and reuse for greywater and irrigation. Energy systems include photovoltaics and geothermal energy that minimizes building operational energy. Air systems include cross ventilation and carbon dioxide absorption from bio-concrete. As stated earlier, the Sustainability Center of Uptown Charlotte aims to educate its patrons not only through second hand resources but through firsthand experience.
2: Regional/Community Design
Tryon Street is the spine of Uptown Charlotte. The main street connects numerous cultural centers in the metropolitan area, and has essentially become the city’s cultural corridor. Along this cultural corridor there are buildings reserved for every community from African American art enthusiasts to basketball fans. However, an absent community from this Uptown mix is the sustainability movement community. Placed adjacent to an arts education center and a dance education center this project identifies as a sustainability education center. With the main entrance off Tryon Street, the center for sustainability engages the cultural corridor of Uptown Charlotte. Highly accessible via walking, the neighborhood maintains one of the highest walk scores in Charlotte at 83. Bike storage takes the place of on-site parking for the center for sustainability. By encouraging people to utilize alternative modes of transportation (including the prominent bike share program of Uptown Charlotte) the project becomes grounded within its neighborhood. As well as being educationally and physically integrated into the community, the Sustainability Center is economically integrated. The ten resident artists are co-owners of the entire company. Having owners engaged with the neighborhood encourages local business supplier and service participation. Investing locally, instead of in big box corporations, compliments the region’s economy and therefore increases the quality of life.
3: Land Use and Site Ecology
Located on an infill site within the urban setting of Uptown Charlotte, there is very little natural ecology for the center for sustainability to connect to. However, the city does host numerous pocket parks for pedestrians to escape the hectic city and pause for a few moments. This project will add another small park to the community. The public courtyard, nested within the center for sustainability, acts an oasis from the crowded Tryon Street. With a narrow entrance along the street that quickly expands, the courtyard is a hidden treasure. Along with benefitting the pedestrian, the courtyard is also utilized by the building itself. It is the center of the building’s sustainability systems. The courtyard acts as a sustainability core, providing the building’s source of interior daylight, rain water collection and filtration, cross ventilation, photovoltaic solar gain, and sound barrier control. Other benefits of this project include filtration of storm water runoff from a previously abandoned parking lot, via a rain garden, and air cleansing through bio-concrete façade panels.
4: Bioclimatic Design
According to ASHRAE 90.1, Charlotte, North Carolina is located within a mixed-humid climate zone. This means that Charlotte experiences both heating and cooling seasons with a relatively mild range of temperatures (annual average of 60 degrees Fahrenheit) and high precipitation in the warm months (annual average rainfall of 42 inches). Restrained on the 45 degree angled city grid, the center for sustainability is exposed to harsh hours of afternoon sun on its large southwestern façade. This scenario led the typical metropolitan glass box to become suboptimal. However, instead of removing the glazing and eliminating potential daylight to the interior, all glazing was moved to a courtyard centered within the box, effectively creating a box-void form. The void within the box underwent several daylighting studies during its form development in order to maximize its efficiency while balancing it with solar gain. This process included transformations of widening the space, angling the glazing and expanding the void to the sky. Once the courtyard void was shaped to receive maximum solar gain, kinetic shading panels were applied to the glazing, effectively reducing the external solar load of the building while maintaining possibilities for natural daylighting to the interior. Based on the prevailing wind direction, the southern facing courtyard glazing also introduces opportunities for cross ventilation through the galleries.
5: Light and Air
The program of the building is organized and conditioned for user comfort in four zones: courtyard, service, residential and museum. An exterior space, the courtyard is shaded, but otherwise exposed to the natural elements. The service stack is the southern block of the building and is composed of egress stairs, elevators, restrooms, MEP and storage. A working zone, the spaces take no extra measures for user comfort. The residential block occupies the entire top floor of the Sustainability Center and includes an open studio, administrative suite and private dormitory. Mindful of the individuals that predominantly occupy this level, several windows become manually operated for the optimization of user comfort. For the museum, which is the bulk zone of the program, the windows remain automatic for the building’s efficiency. On either side of the narrow gallery, window openings are automated for strategic cross ventilation purposes. Automation also controls the exterior shades of the gallery, dictating the amount of daylight that enters the space. Outside of passive strategies, a variant refrigerant flow (VRF) system works to efficiently control indoor air comfort and bio-concrete panels work to cleanse the surrounding air.
6: Water Cycle
The entire site’s horizontal built surface area is 16,200 square feet, and it is this entire surface that works to collect water and channel it through the rain garden into the building’s water system. Based on average annual rainfall, this comes down to about 143 gallons of water collected daily by the building. Between plumbing and the HVAC system the building is estimated to consume roughly 156 gallons of water daily (this does not include water that is recycled through the systems). This means that in order for the building to operate only 13 gallons of water a day must be taken from an off-site source. Close to reaching self sustaining efficiency, the building uses 88% recycled water, collects 92% of the water it uses and controls 100% of site runoff.
7: Energy Flows and Energy Future
Energy models were integral to the form development process of this design. Using passive strategies, a building form was crafted that achieved both a minimal EUI (energy usage intensity) and met the urban scale and program requirements. Energy efficient building services and energy production systems were then integrated into the design. 17,604 square feet of photovoltaic panels were installed to harness on-site energy for the project and offset the building’s EUI from 72kBtu/sq.ft/yr down to 10kBtu/sq.ft/yr. When the kinetic façade systems are closed they can produce 86% of the building’s energy needs. The renewable energy source (kinetic PV panels) significantly reduces the building’s carbon footprint. The remaining energy needs come from the geothermal system that uses the Earth as a heat source to offset heating and cooling energy. The spaces are then directly conditioned using the Variable Refrigerant Flow (VRF) HVAC system. VRF systems are adaptable and offer a high energy efficiency ratio (EER), promoting less energy and greater savings. As for future energy development, it is important to note that the photovoltaic panels are a part of a modular secondary skin structure. They may easily be removed, reinstalled, or replaced with the most up-to-date and efficient technologies.
8: Materials and Construction
The regular structural grid and standard connections allow for the building’s concrete foundation and recycled steel frame to be quickly and accurately erected. The dedication to modularity and universal connections reveals an opportunity for the material to be recycled. An essential element to the near net zero building is the prefabricated kinetic mega-unit facade. Carefully crafted off-site, white triangular photovoltaic panels are fixed to rods within a modular frame. These rods allow for each panel to rotate independently. The modular frames are then configured to accommodate large triangular frames along with a curtain wall assembly; this becomes the kinetic mega-unit. The project requires 22 of these triangular mega-units, each of which spans two or three stories in height and 36 feet in width. Once the kinetic mega-units have been delivered to the construction site they are quickly installed onto the building’s primary structures. With modular prefabrication an intricate assembly process takes place off-site, significantly reducing the construction schedule and securing a high level of workmanship. Additionally, bio-concrete panels integrated with biological materials are prefabricated off-site, this allows the lightweight facade system to quickly be attached to the building’s structural frame. One last benefit to both the kinetic mega unit and bio-concrete panels is that the façade system units are independently structured and are thus easily replaced or repaired as needed, extending the building’s overall life span.
9: Long Life, Loose Fit
Three factors contribute to this building’s adaptability: residents, floorplan and location. The residents of the center for sustainability keep the exhibits relevant. The resident artists live within the community they serve, this gives them firsthand experience in seeing what it is that their neighbors need or want, and makes it so they are able to cater the art directly towards them. This allows the museum to evolve with changing trends, aiding in its overall longevity. The second factor that will extend the life of this structure is the open floor plan. All prescriptive functions such as MEP and restrooms have been zoned into edge areas, allowing for the central bulk of the building to remain open and adaptive. An open floor plan allows for the spaces to be versatile to different future needs. The final factor contributing to this project’s long life and loose fit is its location. Within walking distance to the site are offices, apartments, schools, shops and restaurants. If the building were ever to change ownership, it is located in an area that would welcome any number of possible program types; and its open floor plan has the capability to easily adapt to another building typology.
10: Collective Wisdom and Feedback Loops
This project has taught me that while the basis of every sustainable structure is built upon strong fundamental passive design strategies, the design process does not end there. A true sustainable building does not only consider its site and form but also its methods of system efficiency and sources of renewable energy. I also came to realize that architecture can take sustainability beyond its structure. Education is perhaps the most powerful tool the sustainability movement has. An educated community is a competent and capable community. For future projects I will be exploring ways to not only achieve sustainability within the structure with form, systems and renewable resources, but also reach to succeed in spreading sustainability off-site through forms of direct or indirect education.
Faculty Sponsor: Kyoung-Hee Kim