GROW YOUR COMMUNITY: HEMP AS A CONSTRUCTION STANDARD
Serving as an industrial resource far back past the foundation of our country, hemp could be the answer to making American communities more sustainable. Residential construction is of great importance because the rapid growth of our communities and massive urbanization bring a demand for diverse and affordable housing. The natural properties of hemp open up the possibilities of a healthier built environment for both the occupant and its surroundings. By accessing the properties hemp offers, a community can become more resilient to fire, pest, and increase the overall quality of life.
THE FIRST STEP: INTEGRATION OF HEMP IN MODERN BUILDING MATERIALSWhen considering the sustainability of a building, many overlook the energy that is expended in transportation and assembly as an important factor. Concrete, a building staple is a material that requires a lot of energy and is not forgiving, as in mistakes cannot be made without destroying and rebuilding. A study conducted by Iowa State University Center for Transportation Research and Education found that most of the waste produced in concrete assembly ends up wasted in landfills (16). In steps Hempcrete, a product that utilizes the bonding properties of natural hydraulic lime with the woody fibers found in the hemp core (21). Hemp can be grown locally and mixed on site, greatly reducing energy expended in the processes of production (18). Additionally, products such as plastics, wood paneling, even roofing materials can be integrated with hemp to take advantage of its properties. In fact, according to an economic study of industrial hemp conducted by the University of Kentucky in 1998, "plastics were originally developed using an agri-base that included industrial hemp". (19)
One of the more interesting properties of Hempcrete, specifically, is it acts as a natural insulator. This means that space does not need to be made for an extra layer of insulation as many buildings require. A separate application of hemp insulation can be sprayed on walls that are not Hempcrete as well. This means that new homes aren't the only buildings that can benefit from this super crop. (20) |
At BRE's Innovation Park, the Renewable House attempts to demonstrate that sustainable housing is efficient and can be affordable. Here, the natural carbon locking ability of Hempcrete, which is used in the walls of The Renewable House, is being explained.
This video is documents a study conducted in Ireland by local architects to test sustainable material alternatives, and in this case, Hempcrete. As stated in the beginning of the video, the goal of building with hemp is to provide a low energy method of making buildings energy efficient. To discover more from the producers of the video, please visit http://www.sustainandbuild.com.
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Did You Know...
This year, the U.S. Green Building Council reported that 38% of all CO2 emissions come from buildings. Green Buildings on the other hand, require 25% less energy and have 34% lower greenhouse gas emissions. http://www.usgbc.org/articles/green-building-facts
This year, the U.S. Green Building Council reported that 38% of all CO2 emissions come from buildings. Green Buildings on the other hand, require 25% less energy and have 34% lower greenhouse gas emissions. http://www.usgbc.org/articles/green-building-facts
HOW CAN HEMP CONSTRUCTION IMPROVE THE QUALITY OF LIFE?
As it has been stated, building with hemp can vastly improve the health of its inhabitants and the overall quality of life for the whole community. How, and does it really matter when compared to current building standards? One of the more attractive features of hemp-based materials is its ability to sequester carbon. Previously referred to as its "carbon locking ability", sequestration involves the process of removing carbon emissions from the air and locking it in the Hempcrete mixture (21). After the energy cost of transportation, one square meter of hemp-lime wall stores 35.5 kg of CO2 (22). Absorbing carbon from the environment is just one way hemp materials can improve the quality of life in the community setting. Additionally, the mixture is known as "vapor active", meaning is is able to control the amount of moisture in the air by absorbing and releasing it (22). This means that the interior of a building is more breathable and the temperature is controlled by the amount of moisture in the air. This, along with the natural insulation properties, help greatly reduce the amount of energy used for internal temperature.
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Above is the CDL Green Gallery, an extension to Singapore's Botanic Gardens Heritage Museum. The exterior is clad with hempcrete which was selected for its durability and thermal performance which is ideal for the required internal temperature. Hempcrete helped this building become Singapore's first zero-energy building. http://www.dpa.com.sg/projects/cdl-green-gallery/
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Concerning the safety of a community, hemp is naturally thermal resistant. In the video to the left, author of Building with Hemp, Steve Allin, demonstrates the resistance to fire that Hempcrete has. At the end of the video, the brick has barely suffered cosmetic damage (23). Additionally, since the hemp plant doesn't require any type of artificial pesticides, a home is protected from termites or other pests. These features help increase the resiliency of the community that hemp is used in.
A highlighted feature of building with hempcrete is its biodegradability. When the product is done being used, it can be saved for later reuse, or added to the soil. Instead of being demolished and sent to a landfill as waste, the mixture will biodegrade over time and release nutrients into the soil, according to a document prepared to make a case study on Irish construction that integrated hemp materials (24). |
THE NEXT STEPS: HEMP NOW
The possibilities of hemp construction practices should leave no question to the legalization of the resource. Currently, using Hempcrete in the US is not cost effective because it is illegal to grow here. By using hemp, local farms will be stimulated and receive support from nearby communities. This increases sustainability by decreasing energy expended for transportation. Many countries like Ireland, the UK, Australia, and Canada have taken a lead with hemp building. Because other countries have had time to experiment with different methods, the US will be able to know what has worked and is most effective. Now is the time to take an active role in the fight for hemp.