Small changes on a large scale make a huge impact. This is a simple concept and if applied it will improve the countless number of buildings that make up our total global infrastructure. NYC claims around 975,000 buildings and they account for 79% of this cities green house gas emissions. When it comes to residential and commercial infrastructure we can improve it in two ways, through few but very large projects such as the one billion dollar Bank of America building at 1 Bryant Park, or with a higher number of smaller projects, for example $700,000 Brooklyn brownstones. Either way, the idea is to improve our infrastructure by implementing building practices that maximize efficiency and reach for the ideal of sustainability.
Brownstone green renovation is a concept that provides solutions to the many brownstone building owners in NYC. By specializing in a particular type of building a contractor becomes equipped with all the solutions that work in that specific case, and efficiency in the process is maximized. Striving to create net zero brownstones is a goal not easy to achieve, but as time goes on and our incipient green technology begins to bloom, this ideal will become the standard. Anything short of a net zero brownstone is relatively brilliant and each renovated and retrofitted brownstone will be part of the sum that makes a real difference. Equally but vertically, superstructures are embracing this philosophy, and NYC’s first platinum trophy is occupying the two acre lot at 1 Bryant park.
The first LEED platinum sky scrapper in the United States was completed last year and is located on 42nd street and 6th avenue. The Bank of America tower at 1 Bryant Park was the vision of Richard Cook from Cook + Fox Architects, but the hard work of many union tradesmen, designers, and construction managers made it a reality. The goal of the project was to create a building that uses 50% less energy than a building of comparable size. Some creative energy saving features, resourcefulness in allocating material, and beauty in design make this tower a 1,200 foot symbol of the construction industries new priorities.
Most of the materials were sourced from within a 500 mile radius. Also a high priority was placed on using recycled materials. The greatest amount of material used in such buildings is in the form of steel, concrete and glass. Of the 26,000 tons of steel used on the structure at least sixty percent of it was recycled from scrap metal. The blast furnace slag, a byproduct of steel production, is usually discarded but for the Bryant Park site this slag was reused to make up 45% of the concrete mix. By using recycled slag to make a stronger mixture it reduced the amount of cement needed thus saving 56,000 tons of CO2 emissions from being released into the atmosphere. Just to make this fact more relevant let us compare a passenger car driven by an average driver in the USA; such a vehicle puts out just under six tons of CO2 emissions per year. Recycling the slag had the same effect as the equivalent of taking around 9,000 cars off the road for one year. The tower is covered and outfitted with eight thousand panels of crystal and glass. The exterior glass panels have a special coating that keeps heat and UV out, while letting light in. This implement saves money on cooling costs, and by reducing the heating up of the building it also reduced the tower’s contribution to the heat island effect.
This building has some neat systems and I will only describe some of them. The HVAC system was designed to minimize energy usage and ensure high air quality. The air intake located on the upper floors pulls in air and moves it through the filtration media, this air is then circulated throughout the building and released to improve air quality in the building’s immediate surroundings. It would be interesting to test air samples along an increasing distance from the building in order to observe its effects on ambient air quality. Radiant floor heating in the lobby heats the floor and air 5-6 feet above it instead of all 30 feet of vertical space in the foyer. I’m thinking warm air moves up away from the floor anyway but I hope it lingers long enough to keep the passing crowd warm. Forty four frozen water tanks act as batteries that store cooling power. During off peak hours energy is put in to freeze the water and during peak hours the frozen tanks are used to cool the building. This timing of energy usage relieves the energy grid during peak hours. The buildings gray water system collects and reuses almost all rainwater and most waste water. It stores gray water in five different tanks that can hold a total volume of almost 78,000 gallons. Estimates show a potential of saving 127 million gallons of water per year, that much water adds up to savings of about $500,000 annually. The gray water system is also a substantial relief to our sewage system which has enough trouble processing NYC’s 1 billion gallon per day usage rate.
A design that reduces energy and water usage in such a megastructure becomes very powerful since those reductions pile on. I can’t find the exact number but there must be thousands of brownstones in Brooklyn and if so then they add up to millions of square feet of infrastructure. Each square foot is waiting to become more healthy to live in, more energy efficient, and in general more sustainably built and managed. Minor changes on all this square footage adds up to real changes in our infrastructure. Its up to the New York green contractors to provide the methods and solutions that work, and the building owners to select the most forward looking contractor they can afford.