Building Green at Ground Zero

When rebuilding at the World Trade Center site, New York has the opportunity not only to replace the buildings, but to build places that are safer, more energy efficient and better places to live and work. We can set a model for cities throughout the world.

I have been active in New York New Visions, a coalition of design and architectural organizations working on rebuilding lower Manhattan. One of the ideas we have been advocating is to build so-called "green" buildings at the site. Building "green" means that architects and engineers consider environmental factors, such as lowering energy use, maximizing natural light, and using building materials that are safe and environmentally sound, when they make decisions. People who live or work in buildings without adequate light, or offices where fresh air comes in from a traffic-filled street, understand how important these environmental qualities are.

Building green can cause us to think across categories and fields and integrate culture, technology and urban life. The New York New Visions coalition developed a plan for the rebuilding of Manhattan that focuses on several key points.

The design for the site should create green space, which often means park or plaza-like spaces. One example of how such space works to make buildings, even tall buildings, better places for people passing by is the skating rink and plant-filled esplanade at Rockefeller Center. The Winter Garden at the World Financial Center was (and will be again) a plant-filled, open space that many people enjoy. In other countries, smaller planted areas on higher floors of office buildings remind people of nature and help improve the air inside a building.

It is important for the site's design to create spaces that are full of light and air. Windows allow natural light into a building, but there are many different methods beyond just windows. Skylights can help, as can long horizontal bands of glass high up to help light bounce back down off of ceilings. Having windows on the wall that open also makes sense for a variety of practical and psychological reasons.

The buildings must have systems to filter out noxious particles suspended in the air. For instance, air from a medical clinic has to be taken out of the building, rather than being re-circulated, to avoid spreading germs. Understandably, tuberculosis clinics often have the best air standards. Of course it is also important to consider where that outside air is coming from. Air intakes located near a truck loading dock do not make sense. Getting the air intake away from the street is one easy way to make a building more "green."

Developers and construction companies should screen out materials that contain toxins and carcinogens to protect the health of people working at the site. Increasingly, architects and interior designers are looking at "alternative" materials. For example, cork wall tiles and bamboo flooring were not widely used in this country a decade ago. They both are non-toxic, durable, and can be recycled.

Buildings should not use any more electricity for lighting, heating, or air conditioning than is needed. Increasing insulation in new buildings and using efficient new types of window glass also help.

The city has some sustainability standards out there already. Battery Park City's green guidelines, used as standards for the neighborhood's residential and commercial buildings, have been very effective. Based on the standards set by the Leadership in Energy and Environmental Design's scoring criteria, Battery Park City's guidelines range from using natural lighting to taking into consideration where the materials used in a building are fabricated (since it takes energy to move stone, for example, across continents or oceans).

The environmental guidelines prepared for Battery Park City should gravitate across the street to become a set of standards that the city of New York, the Port Authority, and the Lower Manhattan Development Corporation can use for the World Trade Center site. Whatever is built be configured should qualify for the New York State Green Building Tax Credit, with appropriate financial incentives.

The New York City High Performance Guidelines were developed two years ago for projects throughout the five boroughs. Throughout the city, buildings have been built that follow these types of guidelines, such as libraries in Queens, a courthouse on 161st Street in the Bronx and daycare centers in Brooklyn. One of my favorite recent public projects designed to these standards is the New Children's Center done for the city's administration for children's services. This renovation of an historic landmark, the former city morgue, included "green" aspects, such as natural lighting, careful attention to material selection, and making sure that the building's air comes in from vents that are far above the busy street. It is a bright and lovely building, and a wonderful example of how to design by keeping the environment in mind, even while doing a renovation project.

Green projects like Battery Park City and the Children's Center pave the way for what we all can do now. We need a unified focus on how important building "green" is for the World Trade Center site itself.

Rick Bell is executive director of the American Institute of Architects New York Chapter.