What uses 70% of America's electricity and one-eighth of our water? The city of today. How can waste be reused, energy be saved and climate change be reversed? The city of tomorrow.

Enter the Macallen Building, a 140-unit condominium building in South Boston, which was designed to incorporate green design as a way of marketing a green lifestyle while at the same time increasing revenue from the project. And its the first building in the United States to receive a Leadership in Energy and Environmental Design (L.E.E.D.) Gold certificate.

Located in a primarily industrial area between highways, train and bus routes, and an international airport, the site presented challenges for the project team tackling air and noise pollution, the urban heat island effect, and creating local green space.

"What is exciting about the site of the Macallen Building is that it was a former industrial area, so we are transforming an area of South Boston that had been very run-down," said Monica Ponce de Leon, the project's Design Architect. In fact, the building rises from a narrow plot of land alongside a freeway, its use of the land squeezing out every environmental improvement possible within the project.

Some of the green building features include innovative technologies that will save over 2.2 million litres of water annually while consuming 30% less electricity than a conventional building.

This project was chosen as an American Institute of Architects Committee on the Environment (COTE) Top Ten Green Project for 2008.

Structural Steel and Other Materials

A unique staggered truss system was used for the Macallen Building, an unusual application for a residential building, yet very efficient in the amount of steel that is required. The staggered truss structural system allows for efficient use of space, allowing for higher ceilings and increased open-plan area without the interruption of columns. These large open spaces can be adapted for countless uses over the lifetime of the building. Rooms can be reoriented and repurposed, walls moved, and floor plans changed over time as the occupant's requirements change. The building also could be completely repurposed to office space, community college or other uses, providing an accommodating structural system for the first step to a long-term adaptive reuse.

Staggered Truss System 

All of the steel materials used in the construction were fabricated from 95% recycled steel. The project team chose rapidly renewable resources such as bamboo, cork wallpaper, grasscloth wallpaper, wood-fiber ceiling tile, linoleum flooring, wheatboard, and cotton insulation. Of all the wood used in the project, 75% is certified to Forest Stewardship Council standards. In addition to steel, several materials used in the building have recycled content, including concrete, aluminium siding, rigid insulation, carpet, floor underlayment, and bicycle racks. Many of the materials came from sources within 500 miles of the project.

South Elevation

The contractor recycled 90% of the construction and demolition waste, drywall scraps were segregated from other waste and returned to the manufacturer for specialized recycling. And to insure ongoing recycling from the building occupants' waste, on-site recycling management is available for residents with a recycling center on each floor.

Environmental Aspects

This LEED Gold project has a sloped green roof that controls storm water drainage, filters pollutants and carbon dioxide out of the air, reduces heating and cooling loads, reduces the project's contribution to the urban heat-island effect, and provides an ecosystem for wildlife. A 1,858 m² outdoor terrace incorporated into the building provides similar benefits as the green roof. In addition, a covered garage was integrated into the building to reduce overall square footage and contribution to the urban heat-island effect and storm water runoff.

The extensive green roof on the top of the building, shown in this photo, lowers heating and cooling laods in addition to managing stormwater.

The building is well insulated and features several energy-saving technologies, including heat-recovery ventilation and water-source heat pumps. No potable water is used for irrigation on the site. Instead, rainwater and air-conditioner condensate are collected and stored for use. In addition, the project was awarded a LEED innovation point for the use of a system that treats cooling tower blowdown water without chemicals for use in irrigation.

"43 or 44% of US greenhouse gas emissions come from buildings. Heating and cooling buildings. Lighting buildings. So if the building sector doesn't start to do things differently, we're not going to be able to solve the problem of climate change," notes Eileen Claussen, Pew Center for Climate Change.

The Greening of Southie, Capturing the Challenges of Change

During the build, a video crew was onsite, as well as two roof-top cameras on neighbouring buildings that captured the construction from beginning to end. The Greening of Southie is the resultant feature documentary about Boston's first residential green building and the skeptical workers who are asked to build it. The Macallen Building is something different-a leader in the emerging field of environmentally friendly design. But Boston's steel-toed union workers aren't sure they like it. Funny and poignant, The Greening of Southie is a story of bold ideas and a small cadre of unlikely environmentalists who come to connect their work with the future of their children -- and the future of our cities. Click below to watch an excerpt of the movie, which includes time-lapse video of the steel truss construction.

In addition to a broad range of floor plans and unit designs, the Macallen Building offers an exercise facility, swimming pool, hybrid community car, quick access to public transportation, bike paths and recreational facilities, and ground floor retail vendors. Sustainable design strategies include extensive use of recycled and rapidly renewing materials in construction, as well as recycling 75% of construction debris, diverting it from landfills. Each unit has fresh air ducted independently, significantly improving indoor air quality, and a sloped green roof aids in energy conservation. The building sits on a three-story parking structure with parking for 290 cars.

Click the video below to see a montage of Macallen Building imagery.

• Case Studies Database, U.S. Department of Energy's Building technology Program, High Performance Buildings, available through www.buildinggreen.com/
• The Greening of Southie website
• American Institute of Architects COTE Awards
• Macallen Building photographs: John Horner, John Horner Photography

Visit the architect's site

Visit the Macallen Building site