Since the human race has inhabited planet earth, the sustainable use of the resources provided by nature, the use of hemp, has been a fundamental part of our evolution and well-being, improving our quality of life over time.
However, over the last approximately 250 years and accentuated during the industrial revolution, the deterioration of ecosystems has been occurring progressively and alarmingly. In addition, the amounts of carbon dioxide in the atmosphere have doubled in those years.
Some of the most polluting current industries include oil, paper, cotton, and mining. However, today, the negative impact caused by traditional construction and building is increasing due to various variables (energy consumption in extraction processes, production, manufacturing, transport, pollution from the release of gases and dust into the atmosphere, population growth, energy consumption of each housing unit, etc.) calling for efficient solutions with low environmental impact.
Hemp use in construction[/caption>
Environmental impact of growth and progress
The unbridled economic growth and progress have been fueled by the misuse of hydrocarbons as fuels, and by the petrochemical industry with the plastic polymers derived from them.
The accumulation of greenhouse gases in the atmosphere; deforestation of native forests; soil erosion; tons of waste made with plastic materials that are difficult to degrade in bodies of water and on land; among other evils, strongly impact climate change and other environmental problems that are happening and threatening today.
This form of production is unfeasible in the long term, which is why in the ’70s, various organizations proposed a radical paradigm shift.
According to construction engineer (Univ. Of Valparaiso, Chile) Katia Basaure Rodriguez * the conventional way of construction is a concerning issue to address. “The environmental impact is a complex problem affected by the construction industry due to its high energy demand in the manufacturing of processed materials, contributing to a significant increase in global carbon emissions (CO2), which amounts to 56%. Of this, 47% is generated by the use of buildings (heating, lighting, air conditioning), and 9% comes from the manufacture of construction materials.”
Incorporation of hemp use in construction
Thus, innovation has been achieved within the construction industry with environmentally friendly, green, low environmental impact, highly efficient materials with low energy consumption throughout their life cycle, transforming homes into efficient, healthy, habitable, comfortable places that help combat global warming.
These plant-based materials, which even during their production phase (growth) help reduce the amount of CO2 (carbon dioxide) in the air, absorbing it and exchanging it for O (oxygen).
A crop that meets all these requirements is “hemp” (Cannabis Sativa with almost no THC).
In this sense, Basaure Rodriguez clarifies “Hemp fibers are increasingly used in the industry as a substitute for fiberglass. The advantage of replacing fiberglass with hemp is that the latter is lighter, as strong or stronger, biodegradable, and more cost-effective.”
She adds that “The hemp stem consists of fiber and shives (hurds), which are very light, durable, and very resistant. This is increasingly being used in different construction materials, which have excellent thermal insulation qualities, with very low thermal conductivity, and at the same time, it is the cheapest part of the plant.” For this reason, in recent years, different companies choose to use this material so noble. In fact, many young companies have flourished thanks to the use of cannabis plant for construction.
It’s worth mentioning that most of the hemp stalk consists of shives, which, in turn, the use of hemp is the cheapest part of the plant and, before discovering various construction uses, it was burned in the fields.
Construction, then, was an ideal outlet for the large volume of this material and its low cost. Historically, the cannabis plant had been used to build homes, but in a rudimentary way, not as it is today, proposing design and architectural avant-garde. In the market today, we find, for example, hemp blankets, compressed earth bricks and hemp fibers, rigid prefabricated panels, insulating mortars, hemp felt rolls. Also, hemp concrete is created (lime, hurds, and water).
Industrial varieties of cannabis or hemp are very low in THC content, the psychoactive compound found in large quantities in recreational/medicinal cannabis.
In Europe, there are more than 60 registered varieties of hemp for different uses, either for seeds, resin extraction, or for biomass, as well as according to the climate where it will be cultivated. The hemp plant is appreciated for its long stem with few branches and strong fiber, while the psychoactive variety is chosen for its flowers and sturdier shape.
Industrial hemp is planted at around 200 plants/m2, while smokable varieties are around 1 plant/m2. It could be stated that hemp is agriculture, while that cultivated for its flower is generally horticulture.
This house used hemp in construction
Hemp does not need fertilizers or pesticides for its development. It grows fast, chokes out weeds, and is drought-resistant (it needs 4 times less water than cotton). 10 hectares of hemp provide more useful fiber than 40 ha of forest and do so in five months, reaching 4 meters in height in less than six months, instead of the 10 to 20 years that trees generally take. For some authors, it is the plant that produces the most biomass in such a short time and with zero-kilometer production.
We are in a strategic and exploitable position to use the hemp resource again as it was in the past, adding the acquired knowledge as Basaure Rodriguez says in her research work, it can be deduced that the use of hemp in rendering mortars has good acoustic and thermal results, ideal for application in light constructions.
Continuous technological advances throughout the industry are an advantage for the resurgence of the plant species both for cultivation and manufacturing, allowing an unprecedented rebirth at an agronomic, industrial, and commercial level. It is perfect for community, family, or small-scale agriculture due to the low input costs and high yields. There is innovation and local professionals with the capacity, grounded in the hemp history of the region. The future is being built.
By Germán Pereira (RecetasCañameras)
<a href="https://www.youtube.com/channel/UCr
