Hempcrete

Hello everyone!

So I did a project for Sustainability that I would like to share with you all. In this project, I am discussing the hemp plant and how truly wonderful is.

The material that has been chosen for the following piece is hempcrete, hempcrete is an alternative to traditional concrete, it is made from the hemp plant which is dried out and added to water to form a strong concrete-like material that is environmentally sustainable and has a much smaller carbon footprint than traditional concrete mixtures, it contains no toxic ingredients and is cheaper and stronger than concrete. 

The following project will aim to demonstrate all the relevant and necessary information on hempcrete to formulate a conclusive and educational opinion on the subject. The piece will include how hempcrete is made and where it comes from. The study will also show the cost and process involved in creating hempcrete as a material. Next, the study will ask the question of what the difference between hempcrete and concrete is. After this, the report will show the carbon impact of hempcrete. This section will be rounded together in a piece known as the prebuilding process.to formulate a proper answer both the pros and cons of this section will be thoroughly evaluated.

The next section of the piece will look at the construction process of hempcrete, here we will see how builders interact with the product. The next stage in this process will be seeing if there is extra training needed to use this material. Then we will look at the safety side of hempcrete, see how it’s used and if new or additional machines are used when building with hempcrete.

Finally, we will look at the aftercare of the product we will look at the lifecycle of hempcrete and see what is needed to preserve and get the best out of the product. We will compare the lifecycle of hempcrete versus concrete and conclude with a piece showing all we have learned in the research piece.

How Hempcrete is made? (Pre-building):

Hemp plants usually grow up to 4876mm tall, these plants also naturally help tidy up thrives best in drained fields with a great level of natural material. Hemp plants are easy to grow and no need any special treatments as the plant is more itself resistant to weeds and pests. (That's Farming, 2020)

The hemp plant seeds can be used for a variety of goods for different uses such as Fuel cosmetics, moisturizers, paints, protein powders, animal feed, healthy oils (CBD) and many more. (That's Farming, 2020)

From hemp plants, straw can be used for the manufacture of insulations, strings, building materials such as concrete replacement (hempcrete), clothes, fabrics, animal bedding and more. (That's Farming, 2020)

Hempcrete was founded in the mid-1980s, in France, where people tried to find a suitable alternative for insulation and for deteriorated wattle in the old-fashioned timber-frame houses.  (Mother Earth News, 2020)                                          The image was accessed from Google Images on 20/02/2020.

Hempcrete is a similar material to concrete, except for it’s made by mixing water with a wet lime-based blinder and hemp hurds, this leads to more sustainable and economical insulation but also as finishing, by reducing the costs and making the building process easier and faster. As well as this hempcrete can be used as floors, roof insulation, and walls.

What makes hempcrete sustainable is that hempcrete absorbs and emits moisture to regulate internal humidity, it is breathable, and it avoids mould growth. Hempcrete is reducing construction cost, it’s environmentally friendly and is a very light material. (Critical Concrete, 2020)

Differences between Concrete and Hempcrete

Concrete is a combination material that is made from a mixture of cement and water + (fine sand, thick of course as gravel may be used too). (Quora, 2020)

Hempcrete is an Eco-friendly material produced of the deep wooded core of hemp that is then mixed with a lime-based binder. (Mother Earth News, 2020)

Both images were accessed on 20/02/2020 from Google Images.

·         Concrete is used extensively in buildings, dams, bridges and, roads. However, hempcrete is not used to construct load holding structures. (Quora, 2020)

·         Concrete is much heavier in weight than hempcrete. (Quora, 2020)

·         Concrete can be withstood against direct exposure to rain or other weathering agencies, but hempcrete cannot. (Quora, 2020)

·         Hempcrete is often used for sound insulation. (Quora, 2020)

Hempcrete is also easier to work with than concrete with its lime-mixes and acts as a moisture regulator as well as an insulator, it also lacks the brittleness of concrete and does not need expansion joints. Hempcrete material is suitable for nearly all climates as it combines insulation and thermal mass. (Quora, 2020)

Carbon Footprint

Hempcrete is “Better -than-zero-carbon” material, by growing of the hemp plant more carbon is actually taken out of the atmosphere as a result of this production and application onsite. In UK manufacturer of hempcrete materials has suggested a figure of 110 kg CO2 sequestered per m3 for spray applied-hempcrete, and of 165 kg net CO2 sequestered per m3 shuttered and hand-placed hempcrete.  (UK Hempcrete, 2020)

Hemp plant absorbs a lot of carbon dioxide because the plant grows tall, as well as this it’s fast-growing which needs to create a hard, strong stem to support itself when it’s fully grown. The hemp plan can fully grow in just four months in the UK climate.  (UK Hempcrete, 2020)  

The strong part of the stem is chopped up and used for building, no ways the whole plant can be used so nothing goes to waste. (UK Hempcrete, 2020)

The image showing the stem of the plant was accessed from Google Images on 20/02/2020.

Hempcrete is also more sustainable than wood, varying on how many years it takes for the tree to grow, as well as the species. Because hempcrete is a rapidly growing plant, it is an extremely renewable material. (UK Hempcrete, 2020)

Pros and Cons:

The main focus behind every building being built today is simple: to use more sustainable materials because it helps to reduce the pressure on natural resources and it also reduces the negative impact that humans create on the environment. Try using more recycled or reused materials so there will be less waste too. (Erdas, 2020)

 The most important benefit of hempcrete is that it helps the environment. By using hempcrete in the construction it reduces carbon footprint by decreasing the number of toxic gases that are left free into the air. By using sustainable materials like hempcrete climate change is slowed down, and a positive contribution to saving our planet is made.  (The Creative Axis, 2020)

The image is from Google Images, accessed on 20/02/2020.

By using green building materials less damage is made, this means getting away from bad toxins and having the ability to be able to breathe clean fresh air. Research shows that having a good indoor environment it enhances tenant’s quality of life by reducing the inhalation of toxic substances and avoids serious illnesses. (Indoor Air Quality, 2020)

Studies have shown that employees that have been working in green built properties improving their work performance, have better concentration and focus abilities. They also enjoy working in improved quality offices, not even that by using green materials are beneficial to humans, but by increasing productivity in work leads to a better economy. This shows that using green materials increases work performance in offices, but it saves money and slows global warming too. (Indoor Air Quality, 2020)

Hempcrete is a breathable material, that allows being regulating indoor humidity and temperature. It is also one of the best materials to caption the sound. Hempcrete absorbs acoustic to allowing larger comfort. Current standards of ideal absorption are given a coefficient of 1 NRC, while hempcrete acoustic absorption is about 0.69 NRC.   (Acoustic absorption of hemp-lime construction, 2020)

The image compares the NRC of hempcrete to other common materials. The image was accessed from Google images on 23/02/2020

Even though hempcrete has many good advantages it also has a few disadvantages that make is less traditional as a construction material. For example, hempcrete increases its capability to retain water and decreases its mechanical performance. This leads hempcrete for strong limitations regarding what it can be used for. (Barbour Product Search, 2020)

Poor mechanical performance is hempcrete’s biggest difficulty as this leads hemp from being used as a weight-holding material. The reason for this is that hempcrete is an absorbent, causing a weak bond to a lime binder which leads to an elastic-like performance. (Quora, 2020)

Studies have been developing a recycled high-density polyethylene (rHDPE) to improve the mechanical potency of hempcrete. An alkali treatment was used that contained in soaking the hemp fiber in a 5% NaOH solution, it was then treated with polyethylene mixture, which resulted in increased surface area and surface thickness. This made much better adhesion to the binder of the process. Composite 60% rHDPE volume and 40% hemp fiber surrendered an ultimate tensile strength of 60.2 MPa. (Research Gate, 2020)

 The image shows the Flexural stress of rHDPE/hemp multiple at several fiber fractions with purerHDPE, the image is from Google images, was accessed on 23/02/2020.