You might wonder why the word carbon-capturing has been used a lot lately. Carbon-capturing solutions have become extremely relevant and i’ll give you an example on why.
Just 25 years ago, the forests in Austria captured 18.6 million tons of CO2 per year and constituted the biggest carbon sink. Globally, forests were able to sequester 25% of human carbon emissions annually. Unfortunately, this changed in recent years, as the Austrian forests have become a source of greenhouse gases. In 2023, the Austrian forest emitted 5.4 million tons of CO2 instead of sequestering. How come? The main reasons are extreme weather conditions and large-scale tree-killing bark beetle outbreaks (also known as the bark beetle lps typographus). Droughts make trees more vulnerable to bark beetle outbreaks and these outbreaks have occurred globally within the last two decades. These beetles destroy the wood and decrease the amount of CO2 the forest can absorb. Also, in addition to that, due to climate change, forest conditions are drier and less CO2 can be absorbed in these conditions.
The fact that forests turned into a source of emissions is not only happening in Austria, but is a global trend, also to be found in other parts of Europe and North America.
So what are the consequences for the building sector? Well, firstly, the outbreaks mean that the timber production could be jeopardized by climate change, as bark beetles damage the timber quality is damaged and the volume of timber that is able to be used in industry is negatively impacted. This is problematic, as many policies state that the timber production should increase roughly fivefold to meet the demand of the residential construction industry in Europe by 2030. Also, the production of engineered timber was already under pressure due to the growing demand for this bio-based material in various sectors, where the construction industry will have to fight for its share.
The second massive dilemma is that spruce forests were seen as an important carbon-neutral raw material. As this is not the case anymore, this means that the timber industry is not a carbon-sequestering bio-based material. This has massive implications for plans to reach carbon neutrality and reduce greenhouse gas emissions. Take for example the Metabolic forecast (by the European Union) looking at the impact of timber construction in Europe. This climate report suggests that to reach the target of having 50% of Europe’s residential construction being bio-based in 2030, this would correlate to an 18% drop in carbon emissions in the construction sector. Here, the assumption was made that pine wood has a carbon sequestration rate of 715 kg CO2 eq. per cubic meter of wood. This means the suggestions, targets, and goals of past reports and studies need to be revised to account for forests being a source of emissions. Furthermore, France requires all new public buildings to contain a minimum of 50% wood, Amsterdam requires 20% of new homes to be built with timber or other bio-based materials; all with the assumption that the timber is a carbon sink. On the bigger scheme of things, this has a big effect on the climate policies such as the Paris climate goals, which relies on the forest as being a carbon sink and offsetting some of the emissions.
This means we need to find alternatives to sequester CO2 in buildings, which is where hemp in particular can play a massive role. It’s a powerful plant that is carbon-sequestering and can partly solve the problem of dry soil.
Hemp can be used in crop rotation to increase biodiversity, and is already being done by regenerative farmers (e.g. Alfred Grand on his GRAND Farm in Lower Austria). In a multi-crop system, the roots enhance the soil quality and don’t require any pesticides. Monoculture spruce forests are risky when it comes to pests and disease, and we’d say diversification is the solution.
Another reason for why hemp should be grown more widespread in addition to spruce trees, is that these two materials are complementary. Hemp’s lightweight characteristic combined with timber’s load-bearing capacities allow for a whole new set of voluminous elements to be created, such as walls, roofs, floors, and ceilings. Another reason for how hemp and timber can complement each other is due to the fire resistance of hemp when in the form of the biocomposite hemplime.
Hemp production in Europe is currently dominated by France, as it accounts for 70% of Europe’s hemp production. Austria produces less than 1% of hemp within Europe. We as a start-up are increasing the demand for hemp by making it one of the primary raw materials in our products. We hereby want to shape and embrace the potential of the Austrian hemp value chain to increase the use of biogenic raw materials by choosing hemp as the ultimate crop to improve soil health, biodiversity, and carbon sequestration.
More specifically, hemp sequesters carbon during the plant’s growth and captures more carbon during the carbonation phase of hemplime. This message of using bio-based materials in the building sector to offset the emissions needs to be spread. And this is exactly what we are doing at Hempstatic, promoting all the benefits that hemp has for both the people and the planet. We specialize in pre-fab panel manufacturing of hemplime biocomposites. The added value of our biocomposites is the improved safety and healthy indoor environments we provide. Our biocomposites create great indoor air quality and low/no VOCs. We also provide one of the few bio-based materials that is fire resistance, where no chemicals are used.
So I hope to have given multiple reasons for why including more hemp into the Austrian agricultural system will result in a win-win-win for inhabitants, the building sector and the environment.
Whether you are in the building sector or not, I invite you all to raise awareness of how it is not guaranteed that timber is a carbon-sequestering building material. In addition, spark the conversation of which bio-based materials should be used more to combat the climate crisis.