The list of benefits of hemp is a biobased raw material. How long do we let the mass application of Still holding back hemp lime as a building material through prejudice?
Hemp lime
Hemp has no equal as an agricultural crop. However, many people automatically make the link with cannabis cultivation. A prejudice that still stands in the way of the development of this renewable resource. Fortunately, producers of biobased building material hemp lime are making good progress, also in the Netherlands.
Biobased building based on hemp
Hemp as an agricultural crop has a long history. The strong fibers have been used for all kinds of purposes over the centuries. However, during the twentieth century, cannabis smoking was introduced to Europe and the hemp crop became increasingly associated with drug use. This negative image overshadowed the many beneficial properties of the plant, which led to less and less cultivation of hemp.
Hemp as raw material
With the increased attention for sustainable materials in recent years, hemp is once again in the spotlight. Objectively viewed, hemp is a very versatile renewable resource. Some interesting facts:
- A hemp harvest yields roughly four times as much raw fiber as a tree plantation of the same size.
- Trees take about 20 years to reach adult size. Hemp takes 14 weeks to do this.
- No insecticides are needed because insects do not like hemp.
- No herbicides are needed because hemp grows too fast for weeds to compete with.
- Hemp grows in almost every climate and type of soil. It is very suitable for planting on land that is unusable for other purposes.
- Between 1.7 and 1.9 tons of CO2 are absorbed from the atmosphere for every ton of hemp fiber produced. On average, one hectare produces up to 10 tons of hemp straw.
- The product
- Given the strength of this natural raw material, building with hemp is a promising sustainable way of building. The production process differs per producer, but in general it consists of hemp wood, water and a natural binding agent. Currently, hemp lime is mainly used in ecological construction to form the walls in timber frame construction projects. A wall made of hemp lime provides excellent heat and sound insulation due to the natural properties of the plant. In addition, it is vapor permeable, resulting in a healthy and comfortable indoor climate without mold or high air humidity Furthermore, it is resistant to fire and vermin and weighs a lot less than traditional alternatives.
All these positive properties and yet hemp lime is not yet widely used. Apparently the drug image still clings to this crop, despite the fact that the hemp variety grown as a raw material for building materials contains a very low level of the mind-altering substance THC. A completely different product than the stuff that is sold in coffee shops. It is time to ditch prejudices and look purely at the facts. These undeniably show that hemp has tremendous potential as a sustainable raw material.