Recently countries across the globe have repealed bans and have been starting to use hemp for manufacturing building materials such as hempcrete and hemp wool. In the US hemp was legalized in 2018 by the Farm Bill (Kuar & Kander, 2023). In addition, Michigan released the ‘The Industrial Hemp Growers Act’ in 2020. This act outlines the rules and regulations for growing hemp in the state of Michigan (2020). East Michigan in particular, has seen an increase in support for buildings made from hemp materials. This research examines the views of farmers, builders, and city planners located in East Michigan. Farmers' stance on incorporating hemp into their crop production, builders' views on switching from traditional concrete insulators to hempcrete, and city planner’s stance on integrating hempcrete into planning policy will all be considered.
Hempcrete is a building material that is used for non load bearing structures. In a home hempcrete can be used for walls, linings, and roofs. It can also be used to insulate these structures
Hempcrete has been reintroduced into society to replace concrete as a more sustainable material.
The first hemp house in Michigan was built by an East Michigan company; FiberFort. This company has worked alongside Planet Detroit, noticing the environmental injustice issues of public housing within Detroit city, and advocating for hempcrete to be fostered in Detroit (Lugo-Thomas, 2023).
Hempcrete is made from three materials: the wooden core of the hemp plant, water, and lime.
1.) Hemp:
Little to no fertilizers and pesticides (Kuar & Kander, 2023).
Used for crop rotations to improve soil health (Kuar & Kander, 2023).
Its long tap root keeps soil in place and improves top soil quality (Kuar & Kander, 2023).
Used for bioremediation tactics (Kuar & Kander, 2023).
The cultivation of the plant results in negative CO2 emissions as the plant takes in an immense amount of carbon during the growth period (Scrucca et al., 2020).
2.) Water:
One cubic meter of hempcrete = 180 liters of water is required (Step By Step Guide About The Use Of Hemp Lime Binder In Hempcrete).
320 less liters of water per cubic meter, compared to manufacturing concrete.
3.) Lime:
Mining the raw material limestone emits CO2 and other pollutants into the atmosphere. It also disrupts ecosystems and contaminates groundwater (Rhydwen, 2018).
Manufacturing
Manufacturing the lime, water and hemp results in CO2 being released during the calcination process. CO2 then gets taken in during the carboination process. Hempcrete takes in so much carbon during this process that the manufacturing of the product results in a carbon negative impact (Arrigoni et al., 2017).
Transportation
Hempcrete is eight times lighter than concrete resulting in less energy needing to be used to transport the material (Northey, 2022).
End of Life Cycle
Hempcrete can be composted as it is able to biodegrade without emitting any CO2 or harmful chemicals into the atmosphere (Lugo-Thomas, 2023).
Overall, the process of manufacturing hempcrete from using less water, to no cement mixture, to the material going through a carbonation process, this material is more sustainable for populations to use moving forward.
. Concrete is made from aggregates, water, and cement (Gregory, 2021).
1.) Aggregates Three Methods of Procuring:
Quarrying - open pit mining which results in habitat destruction and soil erosion (UK Green Building Council, 2024).
Marine and River Dredging - the removal of sediment on a sea or river bed which results in the disruption of aquatic habitats and pollutants being released into the water (UK Green Building Council, 2024).
2.) Water:
About 500 liters of fresh water is used to manufacture a cubic meter of concrete.
Additional water is used for cleaning aggregates and for curing the concrete (Harshit et al., 2021).
3.) Cement:
Portland cement is the most common cement used in concrete, is the source for 90 percent of the carbon dioxide (CO2) emissions affiliated with concrete in the world (Olsson et al., 2024).
Their cement is a mixture of three parts limestone to one part clay (2021).
Limestone is extracted through mining which releases CO2 into the atmosphere and disrupts ecosystems and groundwater supplies (Rhydwen, 2018).
Clay is extracted through open pit mining and results in habitat destruction and soil erosion (UK Green Building Council, 2024).
Manufacturing
Creating the cement involves pouring crushed lime and clay into a kiln. The kiln must be heated up to 2600 degrees fahrenheit which releases CO2, then while in the kiln the chemical reaction that occurs will also release CO2. This results in cement production generating seven percent of the world's greenhouse gasses (Gregory, 2021). Once the water, aggregates, and cement are acquired they are mixed and cured into concrete.
Transportation
The transportation on concrete requires more fossil fuels than hempcrete as the product is heavier.
Hempcrete provides a variety of social benefits to a homeowner.
1.) Mold Resistant (Lugo-Thomas, 2023).
2.) Insect Repellent (Karche & Singh, 2019).
3.) Fire Resistant (Karche & Singh, 2019).
4.) The installation of hempcrete is currently more expensive than concrete, however the energy consumption costs for the homeowner is lower due to its superior insulation (Karche & Singh, 2019).
Currently the industrial supply chain of hemp in East Michigan is lacking.
1.) No processing facilities located within the state of Michigan.
2.) Not a lot of growth in Michigan with cultivating the plant and manufacturing the product since the Farm Bill of 2018
3.) Potential barrier to the hempcrete market is if farmers in East Michigan would be willing to grow the plant
To begin looking into a green economy this research will dive into:
East Michigan farmers' views and willingness to grow hemp.
East Michigan manufacturers views and willingness to produce hempcrete.
East Michigan urban planners views and willingness to incorporate hempcrete into city planning.
Detroit is home to five of the twenty-five most polluted zip codes in the state (2013).
Detroit, Warren and Ann Arbor ranked 13th in the country for the worst particulate pollution (Mondry & Ignaczak, 2021).
This air pollution is what leads Detroit to have the highest childhood asthma rates of all U.S. cities (Mondry & Ignaczak, 2021).
15 percent of Detroit’s homes are at risk for flooding.
Most of Detroit's homes were built before 1978 (the year lead paint was banned) and when flooding occurs not only does mold begin to grow but lead paint chips (Mondry & Ignaczak, 2021). Wayne County (the county Detroit is within) has been examined by University of Michigan Researchers and the homes purchased in this county have been linked to elevated lead blood levels in children (Eisenburg et al., 2020).
Detroiters are a lot more vulnerable to severe weather. The old homes lack insulation and air conditioning, this leads to less protection from the elements during the summers with heat waves, and during the winters with extreme cold.
While hempcrete can’t resolve companies releasing toxic chemicals into the air or prevent the severe weather events that are frequenting the city more and more due to climate change, it can give residents a buffer. I hypothesize that if urban planners were to investigate renovating these homes to have hempcrete, the draft and insulation problems would be fixed. The health conditions that residents face would not be resolved, but they would be mitigated when they are within their own homes. The hempcrete could also mitigate the exposure residents have to heat waves and cold periods when they are within their homes. It is also mold resistant so when flooding occurs residents would not have to face the expenses of removing the spores. While the hempcrete cannot do anything for the lead paint situation, by renovating homes in Detroit with hempcrete the paint would be trashed in the process. This is how hempcrete can create healthy homes.
The Resource System can be split into the ‘Three E’s of Sustainability’ (Economy, Environment, and Equity). The economic side would be investigating the potential for a hempcrete market in East Michigan. The environmental side focuses on how hempcrete has the potential to be more sustainable than traditional materials used, like concrete. On the equity side of things the Resource System is the theoretical health and cost benefits hempcrete can provide to individuals living in low-income housing.
Resource Units
The Resource Units can also be split into the ‘Three E’s of Sustainability.’ On the economic side, the cost of production versus the profits of hempcrete would be considered. On the environmental side, the farmers who would/ could cultivate hemp on the east side of Michigan are who would be looked at. On the equity side, low-income housing programs and the people who are suffering in unhealthy living conditions are who would be analyzed.
The Government System in this research is the laws by which farmers must abide by when farming hemp. It is also the rules and regulations the different cities planning boards decide to enforce in relation to hempcrete.
The users can be split into the individual level, the community level, the state level, and the national level. On the individual level the users would be the low-income individuals who are currently suffering with unhealthy, expensive housing. On the community level these users would be the urban planners, the building companies, and the manufacturers of the hempcrete. On the state and national level, the users would be the policy makers who determine the circumstances in which hempcrete is used.
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