Bio-based insulation materials: a more sustainable alternative for civil construction.
Made from agricultural by-products or recycled materials, bio-based insulation emerges as a promising alternative for civil construction, as it provides a variety of benefits for people's health and also for the environment.
At the present moment, in the European Union, a high percentage of the energy consumed by buildings is spent on controlling their temperature. Heating and cooling accounts for half of the EU's energy consumption, making it the largest energy end-use sector ahead of transport and electricity . This fact highlights the need for insulation materials in constructions, in order to improve their energy efficiency and reduce the environmental impact of the building stock in Europe.
There are various types of insulation materials available in the market. Yet, not all of them are equally sustainable. To achieve a better environmental performance of the building, it is fundamental to select its materials by taking into consideration not only their insulating properties, but also their complete life cycle. It is necessary to consider issues related to the resources that go into their production, their manufacturing processes, their recyclability and impact on indoor air quality.
Currently, the most used insulation materials are mineral or fossil-based, such as polystyrene, closed-cell polyurethane, fiberglass and mineral wool batt insulation, although it is proved that their production process has a high energy consumption, causes the depletion of limited resources and pollution resulting from mining. These materials can also emit volatile compounds that are a health threat to humans .
Bio-based insulation materials are emerging as a promising alternative in building envelope applications. They are made from agricultural by-products (e.g. cork) or recycled material (e.g. waste paper). A research developed by Jan van Dam and Martien van den Oever at the Wageningen University (2012) points out that the technical performance of several renewable insulation materials, such as cellulose and fibers from hemp and cotton, is comparable to that of the mineral benchmarks. According to the researchers, renewable insulation materials could easily replace traditional products without loss of performance .
When compared to common insulation materials, the bio-based present several advantages. As a renewable resource, natural insulations require much less energy than the conventional ones to be produced. They are also CO2 neutral or negative, as they naturally bind CO2 during their growth phase. Furthermore, many bio-based insulating materials come from regional agriculture and forestry, reducing transport distances, decreasing import dependency and strengthening local economy .
Another advantage of natural insulation materials is their circular life-cycle. Some of them, like cellulose flakes and sea grass, can be reused. Some others, like hemp mats and sheep wool can be recycled.
Scientific research has also shown that most bio-based insulation materials can accumulate and conduct moisture. This moisture-regulating effect contributes to a comfortable indoor climate throughout the year. It also has a positive effect on people's health, especially those with respiratory diseases, for whom constant indoor humidity is important . In addition, natural insulation effectively protects against noise from inside and outside a building. Research shows that flax and cellulose, for instance, are comparable to glass wool and rock wool in terms of sound absorption properties .
Bio-based Insulating can keep up with conventional materials in terms of quality and insulating properties. In addition, it has a better performance in view of the overall environmental impact assessment. Nevertheless, Insulation made from renewable raw materials still plays a secondary role for consumers. But according to the Building Centre (UK), the Bio-Based Insulation Market is growing.
Author: Danielle Khoury Gregorio
Led by: Anna Juda
* Article originally published on the website bambouimmobilier.com
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