Green Strategies in a Historic Preservation Project: King Federal Building in Atlanta
The GSA also has a strong green building directive, which many may see as potentially conflicting with the historic stewardship and preservation mandate. However, historic preservation and LEED certification are naturally aligned in many ways. Many of the resource constraints voluntarily recognized as ethical imperatives of green building were realities of historic design and construction. Passive design strategies such as daylighting and natural ventilation, which are again in vogue for green building, were historically routine practice out of necessity. Due to development patterns that predated the automobile, historic buildings are often located in pedestrian-friendly urban cores, and building materials were largely local due to the high cost of transporting goods on early transportation networks.
Important character-defining features of the building, such as the historic postal hall and monumental stairway, were restored while other spaces were renovated to provide new Class A office space. These features often broght green benefits. For example, the building’s operable windows, as well as the Georgia marble façade, were rehabilitated, and its formerly daylit interiors were restored and augmented with modern high-efficiency lighting with daylight harvesting controls.
One interesting aspect of the rehabilitation highlights the need for knowledge-based decision making when evaluating sustainable preservation options. Often historic building envelopes become a target for modification based upon the perception that they are not sufficiently “tight” to be energy efficient. At the Martin Luther King Jr. Federal Building, the historic building envelope was preserved without alteration, including its uninsulated masonry walls and its large single-glazed steel windows. Evaluation of the energy model indicated that the building’s energy usage was governed by its internal loads. Thermal improvements to the building envelope would have created little improvement to the overall energy efficiency of the building; in fact the energy model indicated that the single-pane glass in the windows actually performed slightly better than an insulated replacement window due to the fact that the single-pane glass allowed heat to migrate out of the building, mitigating the need to air condition the building at certain outdoor air temperatures.
Rehabilitation of the nine-story building is ongoing — five stories have been completed to date — and floors not under construction have always been occupied. Managing an occupied building under construction presents its own unique challenges, including more complex coordination of construction activities and safety measures to minimize tenant interruptions and maintain a safe work environment. At the Martin Luther King Jr. Federal Building, the initial green building focus in design and construction has transitioned into attention to green operations, including implementation of a green housekeeping policy and consideration of future LEED for Existing Buildings: Operations & Maintenance certification.
Jim Nicolow and Susan Turner are principals with architecture firm Lord, Aeck & Sargent. Nicolow is the firm’s director of sustainability. Turner served as principal-in-charge of the LEED gold MLK Jr. Federal Building project. Earlier this year, the Advisory Council on Historic Preservation (ACHP), an independent federal agency, presented its prestigious Chairman’s Award for Achievement in Historic Preservation to the GSA for restoration, rehabilitation, and reuse of the Martin Luther King Jr. Federal Building.