Green Buildings

The consumption of fossil fuels is one of the biggest problems in today's society.  Though cars get blamed as the culprit, buildings consume about half of the energy in the world today (Gissen).  Mechanical systems within the building are now being redesigned and rethought to consume less energy. 
Architects and engineers are designing buildings to utilize light and air in more efficient ways.  Construction practices have been reexamined too.  Materials to create buildings - concrete, steel, wood, plastics - generate environmental problems because of the toxic chemicals and energy put into them that make them fireproof or waterproof (Gissen).  Engineers, construction companies, architects, and developers have teamed up to practice "building green."

Apartment and office buildings that consume energy and resources have been built to specifically reduce their environmental footprint on society.  However, anyone can call a building "green."  To legitimize the principle of "sustainable development" on buildings, the United States Green Building Council (USGBC) created a rating system to award buildings that demonstrate "Leadership in Energy and Environmental Design (LEED)." The certification board examines five different areas of green practice in the building, including, "human and environmental health; sustainable site development; water savings; energy efficiency; materials selection; and indoor environmental quality" (Bauld). The LEED system offers four different types of ratings based off of its green features and construction practices.  The system's "platinum" rating is the highest, then gold, followed by silver, and finally certified (Padalka).

Green roofs, a standard in any building that wants to achieve LEED certification, offer multiple benefits versus the standard black-top roof. A green roof is a roof of a building that is partially or fully covered with soil and planted vegetation across a waterproof membrane. Green roof functions include reducing the amount of storm-water run-off and lowering the amount of energy needed to keep a building at a comfortable temperature.  Other benefits that a green roof provides are added green-space to the urban environment, minimized urban heat-island effect, increased air-quality levels, and elongating the life-span of the roof (Oberndorfer).

Storm-water run-off can be devastating to a local eco-system.  Sewage overflow during periods of rain contains high amounts of pesticides and petroleum residues that contaminate drinking supplies and hurt local wildlife.  Green roofs reduce the amount of storm-water run-off by retaining water during rainstorms.  The system will then discharge that water slowly into the sewage system or recycle the water for other purposes.  Studies in Portland, Oregon and East Lansing, Michigan have showed that green roofs retain 66% to 69% of run-off for a roof with more than ten centimeters of substrate.  Other studies have shown that green roofs can reduce the storm-water run-off effect by 60% to 79% as compared to other normal roofs (Oberndorfer).

During the typical summer months, the amount of energy needed to keep the building at a comfortable temperature increases. Studies have shown that green roofs cut down the amount of energy needed to keep the building cool by about 10% -- lowering the stress on the building's cooling system.  In general, green roofs have the greatest effect on energy usage for buildings with a high roof to wall ratio (Oberndorfer).

Green roofs reduce the heat flux by three mechanisms: evapotranspiration, physically shading the roof from the sun's rays, and increasing insulation.  In the summer of 2002, Penn State University did a study on the amount of water vapor that a green roof would actually evaporate and transpire as compared to other vegetative areas.  The study concluded that a green roof acts comparably to a wet habitat (i.e. a bog), showing that evapotranspiration is the most important contributor of reducing the heat flux.  Green roofs, in addition to better insulation throughout the building, can lead to a building that can reduce its energy consumption (Oberndorfer).

Green roofs are not the only thing that awards buildings LEED points. The LEED certification board looks at all scopes of the project for green aspects, including the early construction stages and choice of materials.  Construction practices require that construction waste be recycled, and that materials used in the buildings development be part of the building's "sustainable development."  Construction companies have resorted to using materials such as recycled steel, concrete made of recycled materials, and bamboo.  These substances are environmentally sensitive as well as economically advantageous.

In the long run, concrete uses fewer natural resources than any other building material.  Concrete can be recycled, and a lot of recycled materials are used in concrete production.  In addition, concrete's thermal mass properties, and its ability to be a good insulator, make it attractive.  Concrete buildings are said to decrease temperatures by about five degrees Fahrenheit and cut air conditioner usage by 18% in the summer months (Popovich).

The Helena, located on West 57th and 11th Avenue in Manhattan, pursued a silver ranking from the U.S. Green Buildings Council. This 37-story, 600 unit, residential building, owned and funded by Durst Organization Inc., gave contractors three main problems in construction.  The first problem was the issue of waste management.  LEED standards require that paper, plastic, wood, and metal are segregated so that they can be recycled and diverted from the landfill.  The construction corporation hired a waste management company to haul these materials and then take them away from the construction site.  This earned the Helena LEED points for diverting material from landfills.  The second problem that had to be addressed was erosion and sedimentation control.  To prevent soil from leaving the construction site and entering into the sewage system, and eventually dumping out into rivers and streams, the contractor installed gravel-pit systems.  The third problem encountered was to maintain the indoor air quality of the building during construction.  This was solved by carefully covering ductwork so that contaminants from the outside did not affect the indoor air quality of the building (Choi).

The apartment units in the Helena were constructed using renewable materials. For example, the floors were made of bamboo and the cabinets were made of wheatboard.  Bamboo and wheatboard are both more environmentally sensitive than the traditional pine or oak used in constructing floors and cabinets.  The glass used for the windows are of high-quality, and there is little heat penetration or heat lost through the windows, conserving heat in the winter and cold in the summer (Choi).

The LEED also awards points if the building reduces water usage up to 20% and then 30%.  One way this is done, is by using grey-water for use in toilet flushing or urinal flushing.  Grey-water is collected storm water run-off and water from showers.  Other fixtures include using low-flow shower heads, which flow at only 1.5 gallons per minute.  In addition, the standard toilets and urinals use 1.6 gallons per flush (gpf) and 1 gallon per flush respectively.  Newer urinals, aiming to cut water consumption use in half, and newer toilets aim to get around 1.35 gallons per flush instead of the typical 1.6.  With these simple measures, for a 100,000 square foot office building with 650 occupants each using on average 20 gallons per day, water use can be cut by about one million gallons per year (Allen).

Additionally, green buildings provide for an economic advantage.  At first, building green was considered a desired, but unreachable, goal. Today, the stamp that a building is green provides a nice little attribute that developers like to tout to consumers (Padalka).  Green buildings have created their own tiny marketplace within society.  The reasons are political, consumer-based, and lower costs.
 
The creation of the LEED rating system has provided some accountability as to what a green building is in the market.  The programs popularity has increased exponentially.  In New York City, five buildings are already certified by the United States Green Building Council, while another 91 buildings are waiting for approval  (Neuman).  Another driving force for the green building marketplace is the laws that have been passed by local governments, in particular, Battery Park City. The passing of the mandate that any future buildings in Battery Park City must be green puts contractors at their heels.  Ashok Gupta, director of the Natural Resources Defense Council's air and energy program, believes that the market impacts will be huge, and that an, "increase in ecofriendly construction will drive down costs and encourage more private developers to go green" (Engquist).

According to various reports, apartment buildings with the green stamp attract consumers more so than apartment buildings without the green stamp.   Today, according to Daniel Tishman, CEO of Tishman Construction explained that consumers are willing to pay a premium for living a green lifestyle.  Tishman goes on to explain the current trend in green lifestyles, "We are starting to see that tenants understand that living in a green building is living in a healthy building" (Padalka).  Mrs. Brandenmeyer, a tenant in the Solaire, at first didn't pay notice to the fact that their building was environmentally sensitive, but viewed it more as a novelty.  She and her husband pay 6,500 dollars a month for their three-bedroom, three bath apartment, which is above the average rent for the building.  However, Mrs. Brandenmeyer's views have changed drastically, "the green part of the building is the most important to me.  I think it should be the standard.  It's night and day different, the quality of living" (Neuman).

The cost of building green has also gone down significantly over the years, making it more feasible for contractors and developers to build green.  Albanese Corporation spent 120 million dollars on building the Solaire, the first residential Green Building.  From those 120 million dollars, 15 to 17 percent of the money went towards making the Solaire green. However, after the Solaire, the Albanse Corporation went on to build the Verdesian, where only 8 percent of the added costs went towards the building's green features (Neuman).  Since then, added green costs tend to average from two to eight percent of a premium (Padalka).  The reason for such a price drop is mostly due to the fact that construction materials for green buildings have also decreased.  At first, according to Mr. Albanese, materials such as chemical free paints, sustainable harvested wood, and photovoltaic cells for solar power were not only difficult to come by, but expensive as well (Neuman).  Now, prices for these materials have dropped significantly.  Chemical-free paint can be found in Home Depot, and bamboo is constantly being utilized to build green ("The Helena").  The biggest example can be seen in the growth of the photovoltaic industry.  According to altPOWER, a sustainable energy consultant in New York City, the photovoltaic industry has grown 20 to 30 percent over the past few years.  The increase in business has also led to price drops across the board for solar power being introduced into green buildings.  With price drops and a better understanding of the cost of green materials, construction companies and developers can better estimate the costs of a green building, making the task seem more desirable and less daunting (Padalka).

Not only have there been price drops in materials, building green has given developers tax breaks that add to the amount of money that can be saved.  New York State's Green Building Tax Credit started in 2000 and offered state tax credit for builders that built sustainable, or built green.  The program called for $3.75 per square foot for interior work that met green standards, and $7.50 per square foot for exterior work on the building that met green standards.  In addition, the New York State Energy Research and Development Authority provides for further economic compensation for green buildings (Padalka).

Sustainable development in engineering is an important principle that must always be considered when starting a new project.  Green buildings fit the definition of sustainable development.  The importance of preserving the environment, especially in such an urban setting like New York City, should always be an important factor.  However, sometimes the goal of "saving the planet" is too lofty and even more important, too expensive.  That is not the case in green buildings.  They are environmentally friendly and economically sound.

Works Cited

Allen, Jim. "Water Efficiency." Environmental Design + Construction. Troy: May 2004, Vol. 7, Iss. 4. 65.

Bauld, Stephen. "LEEDing into the Future." Summit. Ottawa: Oct 2007, Vol. 10, Iss. 6. 12.

Choi, Amy S. "The Helena; Silver and Green Are the Colors in Question." New York Construction 51.8 (Jan. 2004): 25.

Engquist, Erik. "Ambitious 'Green' Law Will Overhaul how City Builds." Crain's New York Business 31 July 2006: 26.

Gissen, David. Big and Green. New York: Princeton Architectual Press, 2003.

Neuman, William. "It's Getting Easier to be Green." The New York Times 13 Aug 2006, late ed.: 11.1

Oberndorfer, Erica, et al. "Green Roofs as Urban Ecosystems: Ecological Structures, Functions, and Services." Bioscience. Washingtion: Nov 2007, Vol. 57, Iss. 10. 823.

Padalka, Alex. "Green Economics." New York Construction 52.8 (Mar. 2005): 39.

Popovich, Charles M Jr. "Building Green with Tilt-Up." Concrete Concepts. Fort Atkinson: Sep/Aug 2005, Vol. 4, Iss. 6. 22.

"12 The Helena." New York Construction 51.12 (June 2004): 83.