The Future of Design?

Eco Office Contractors Seek Southeast's first Platinum Level LEED Certification

By Jennifer LeClaire

A consortium of green builders, architects and supporters are setting out to do with the Southface Eco Office project in Atlanta what no one in the Southeast has ever done before: earn a Leadership in Energy and Environmental Design (LEED) Platinum certification for new construction from the U.S. Green Building Council.

The consortium is made up of Southface Energy Institute, an Atlanta-based nonprofit organization that promotes sustainable homes, workplaces and communities; Lord, Aeck & Sargent, an Atlanta-based architectural firm; and Eco Office Contractors: A Green Building Consortium, a group consisting of five of the Southeast's most prominent general contractors.

The project, which broke ground in early July, could help the Atlanta-based general contractors - DPR Construction, Hardin Construction, Holder Construction, Skanska USA Building and The Winter Construction Co. - to further their expertise with green building techniques. Indeed, 93 percent of building executives working with green buildings expecting their green workload to rise in the next three years, according to a survey by Turner Construction Co. in New York City.

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Owned by the Southface Energy Institute, the first phase of the Southface Eco Office will be completed in the spring. The 10,000-sq.-ft., three-story structure will feature green products and technologies and serve as a model of environmentally responsible commercial construction.

"The building will feature off-the-shelf products and technologies and will give Southface a demonstration facility and a stellar teaching tool to increase by 50 percent our ability to educate the commercial building industry in 'green building' techniques," said Dennis Creech, executive director of Southface.

LEED Defined

All of the sustainable features in the project were designed to achieve Platinum-level LEED certification, the highest of four certification levels.

Obtaining the Platinum certification means going above and beyond the minimum requirements to incorporate extensive elements from each of six rating categories.

"Building green requires an integrated design approach," said Southface green building project manager Frank Burdette. "Architects, engineers and construction managers are involved from the beginning to ensure that the building envelope is designed in such a way that it works in conjunction with the mechanical and electrical systems. But it can be a hurdle to get past some ingrained design and construction habits and get everyone to think out of the box."

Final scoring on the EcoOffice building will be tallied after the construction is completed and all building systems are operable.

Energy Saving Architecture

The Eco Office will harvest energy from the sun, filter its stormwater, collect rainwater for building use and treat its own sewage, said Jim Nicolow, AIA, who leads Lord, Aeck & Sargent's sustainable design efforts.

"The building was sited and the windows oriented to make use of readily available daylight, minimizing artificial lighting requirements and the associated cooling loads," he added. "Our overall goal is to exceed the energy code by 60 percent."

Architects plan to accomplish that goal with the help of optimized facade featuring insulated concrete foam walls, low-e insulated glazing with operable windows and external, operable sun-control devices.

Nicolow said one of the unique features of Eco Office is a canopy of semitransparent photovoltaic panels. The Southface staff rescued these materials, which were destined for a landfill. The panels will simultaneously generate electricity from the sun and provide shade for an observation deck that overlooks a vegetated roof and mechanical system.

Because lighting is typically the largest energy user in an office building, sensors that measure the amount of natural light coming into the building will control electrical lighting in the offices. The system also features occupancy sensors to avoid burning light bulbs in empty areas of the building.

Reducing the Urban Heat Island

The sustainable design avoids the heating levels that lighting introduces to a space. There also is an efficient mechanical system that leverages a dedicated outdoor air-ventilation system with heat recovery fabric ducts and an advanced control system.

On warm summer days, the air in urban areas can be up to eight degrees hotter than its surrounding areas. The Eco Office design demonstrates two ways of addressing the dilemma. One portion of the roof is a reflective Energy Star roof technology. The other half is an extensive green roof that features 4 in. of engineered growing media.

"The roof will reduce the heat so its temperature will be essentially the same as the surrounding landscape," Nicolow said. "That will eliminate the extra heat radiating into the area. The green roof will also filter stormwater."

Water Saving Designs

Other water-saving design elements include porous concrete paving, which allows stormwater to filter through the pavement into the underlying soils, and bioswales, which are a series of planter-like ditches full of native plants to help take up the water and create a bird habitat.

A rain garden is another landscaping feature that is planted with native perennial plants and used to manage stormwater running from impervious surfaces such as roofs, sidewalks and parking lots.

"Atlanta has a small watershed, so Eco Office needed to be a water-efficient building," Nicolow said. "We also have a lot of problems with water quality in our streams and rivers. The porous concrete, rain garden and bioswales help us channel the water to a detention area where it is filtered before it leaves the property."

In addition, no potable water will be used to flush toilets. A combination of foam-flush composting toilets and dual-flush toilets supplied by harvested rainwater will be used. Much like an airplane toilet, the foam-flush toilet uses only 3 to 6 ounces of water. The waste goes to a composting unit.

Recycling for Savings

In addition to the photovoltaic panels, the design incorporates a recycled flooring system that allows for displacement ventilation. The flooring actually delivers air closer to 65 degrees, which allows each office employee to control the temperature in his or her cubicle.

"This project has provided the design team with a great opportunity to get to know and collaborate with other 'green' experts in the field," Nicolow said. "We're all learning a great deal that we'll take with us to future projects."

When completed, the Eco Office will provide much needed office space to support the organization's growing staff and programs as well as providing meeting and training spaces. The district office of the Urban Land Institute will share office space in the new Eco Office.

"About 5 percent of the market now is green buildings, but we are going to see that increase," Burdette said. "The government has embraced these strategies and companies are beginning to understand the benefits of building green. We believe this is the future of building design."