Building a more sustainable future begins with developing innovation for more sustainable buildings.
photo by Ariella Brown
We’re used to hearing bad news about the climate, but there is some very good news. According to the World Green Building Trends 2018 there are more sustainable features going into the building now, though the extent of that improvement does vary by country.
The Whole Building Design Guide (WDBG) explains that the goals “of sustainable design are to reduce, or completely avoid, depletion of critical resources like energy, water, land, and raw materials; prevent environmental degradation caused by facilities and infrastructure throughout their life cycle; and create built environments that are livable, comfortable, safe, and productive.”
WDBG offers several resources for guidance on sustainable design. It also includes a description of buildings that have won Leadership in Energy and Environmental Design (LEED) awards for theirs. Among such buildings are two in New York City that get the message of green across in the most appropriate context possible: a garden.
The Greenest Building in New York City in 2007
In September 2007, the Queens Botanical Garden opened its long-awaited Visitor and Administration Center. The $12 million valued 15,831 square foot building was designed to be a uniquely immersive educational experience, a showcase of beautiful, sustainable design.
The Garden’s site explains that the building was intended to serve “as a veritable encyclopedia of building techniques that conserve water, tap renewable energy, and work with nature.” Its features include the following:
- The green roof is made up of living plants to cut down on heat and water run-off.
- It uses renewable with solar panels powering 17 percent of its electricity and a geothermal system uses 55-degree water pumped from an aquifer to heat and cool the building.
- Water is preserved through two systems, one that captures rainwater, and one that recycles “graywater” from drains to supply the visitor’s toilets after passing through a cleansing biotope.
- The wood used is of the sustainable variety. Most other building materials, including like steel, are recycled and locally sourced.
The Botanic Garden boasts a great number of additional sustainable features to be found throughout the grounds and structures that are mapped out and detailed on its Green Trail.
The Queens Botanical Garden Visitor and Administration Center’s environmentally advanced design made it the first New York City public building to earn platinum certification under the US Green Building Council (USGBC) Leadership in Energy and Environmental Design (LEED), as well as a slew of other design awards.
A Roof Grows in Brooklyn
Once one botanical garden demonstrates what it can do with sustainable design, others have a model to follow. The Brooklyn Botanic Garden completed construction on its own a $28 million visitor center at the end of 2011.
The design by Weiss/Manfredi is LEED Gold–certified. Like the building in the Queens Botanical Garden, the Brooklyn visitor’s center includes geothermal heating, a truly green roof with native grasses and wildflowers growing on it, as well as rain gardens to prevent water run-off, though it doesn’t claim a system of recycling “graywater” or utilize solar panels.
Details of the features that make up the “the 9,690 square foot leaf-shaped green roof” are shared by Greenroofs.com. For example, there are over 40,000 plants on the roof that are intended to take in close to 200,000 gallons of water per year.
Getting down to the foundation: C02 for more sustainable concrete
As innovative and environmentally sound as the buildings topped by green roofs, are, there are other building techniques that are available today for those who are devoted to sustainable buildings. As every building starts off with a foundation, the place to start when thinking of a greener way to build is with the concrete itself.
Sustainable design sometimes results from some surprising additions. In the case of concrete, it’s none other than the compound some have come to associate with the cause of all detrimental climate change: carbon dioxide.
It’s called “CarbonCure Technology.” The way it works is by adding in just the right amount of CO2 into concrete to enable the gas to be transformed into a mineral, and that keeps the carbon dioxide from getting out into the atmosphere.
The chemistry is explained this way: Once it is within the concrete mix, “the CO2 reacts with calcium ions from cement to form a nano-sized calcium carbonate mineral that becomes permanently embedded in the concrete.” In effect, the calcium dioxide mixes with the calcium within the concrete to form CaCO3, solid limestone.
The advantages of using this technique extend beyond the capture of carbon dioxide. As the Lead Innovation blog explains, it also promises produces “greater strength, durability, and lightness than conventional concrete.”
It adds on what makes it a superior product that is worth the higher cost:
- Carbon does not rust. Therefore, in contrast to reinforced concrete, no thick concrete layers are required to protect the carbon. The sand consumption and the CO2 emissions associated with the production of reinforced concrete can be significantly reduced.
- The building material can be produced from any material containing carbon. For example, researchers are currently using lignins, a waste product produced during wood production.
- The load-bearing capacity with carbon is five to six times higher than with reinforced concrete.
- The carbon version is four times lighter and also has a significantly longer service life.
Concrete design that eliminates the need for steel support
While we’ve become used to steel frames in major buildings, there was a time when even massive cathedrals were built without the use of that metal. How did they do it? Revisiting some of those engineering techniques has led researchers at ETH Zurich’s Department of Architecture (D-ARCH) to a new approach to floor design.
As explained here, thanks to incorporating the same trick used to reduce weight in cathedral building, they were able to create “a concrete floor system that does not require steel reinforcement and is 70 percent lighter than conventional concrete floors.”
They key is in the arches, just as it is in the supporting structures of soaring cathedrals. It is that shape that makes it possible to “support very heavy loads and so do not need to be strengthened with reinforcing steel.”
See the technique demonstrated in this video:
As we develop both more innovative thinking in terms of what a building should look like in terms of its shape and what we see of the exterior and turn our minds to rethinking the materials used to construct it and the power sources for its electricity and climate control, we should see even greener results for the future.
Each building that demonstrates new green techniques serves as a model for others to follow to help build a more sustainable future for the planet.
Finead SA