BARCELONA – ‘Fast fashion’ ensures that everyone can wear the latest trends every week. But the phenomenon also leads to endless mountains of clothing that are no longer used. There are said to be 100,000 tons of discarded clothing in Chile’s the Atacama Desert.
Worldwide, between 35 and 95 million tons of clothing waste are produced annually. Besides the fact that used clothing represents a huge amount of waste, the added difficulty is to separate the different sewn elements such as buttons and zippers, but also to separate different fibres according to their composition. That is why most textile waste ends up in landfills or incinerators.
Catalan researchers from the TECTEX research group at the Universitat Politècnica de Catalunya wanted to do something about this and have reached a process to use this clothing waste as a new building material.
In this scenario, the research group proposes a new construction material that uses textile waste. The material (developed on a laboratory scale) includes its composition, in addition to textile waste, binders, and mineral fillers. Its characteristics and properties are optimal for use as cladding for ventilated facades. The recycled material can also be used as a floating floor, false acoustic ceilings, drywall, and other similar applications.
The ventilated facade is a modern building solution derived from the cavity wall. The facades are made up of several continuous layers, like an onion. They normally have an inner layer, an insulation system against moisture and temperature, a ventilated air chamber, and an outer layer of protection. The latter coating damps thermal changes and prevents solar radiation.
Due to its location, this layer must be constructed from a light and resistant material, so that the required supporting structure can be kept to a minimum.
The great potential of new material
In this context, the material developed by TECTEX has great potential. It combines lightness and resistance due to the textile reinforcement. This reinforcement also improves the thermal insulation capacity and acoustic absorption. In addition, the material may also have other functions, such as self-cleaning or thermal absorption, which can be obtained by adding special additives.
Shredded Garment Waste
The material developed is based on shredded clothing waste that forms a thin felt after energy-efficient mechanical processing and without the addition of chemical products. It can also be made into a paste based on cement and mineral fillers. Then the fibre layers are mixed with paste and layered, forming laminates with thicknesses between one and two centimetres, depending on the final application.
For ventilated facade panels, cement is the ideal binding agent, because it is more resistant to weather influences. However, research is being conducted into other more sustainable binders such as lime or mineral polymers.
Result: very light material
The result of this process is a very light material with good resistance to bending and impact.
Environmental awareness in the construction industry
Like other economic sectors, the construction sector is also becoming more environmentally aware and is increasingly focusing on sustainability. This is necessary because construction is responsible for about 35% of CO2 emissions, 40% of energy consumption, and 45% of solid waste in the European Union.
Building use phase most environmentally harmful
This calculation includes the entire life of buildings, from construction to demolition, as well as use. The use phase is the one with the greatest environmental impact. Much is already being done in this regard. Regulations for air conditioning and energy consumption of buildings are stricter. This has led to an improvement in thermal insulation, greater use of renewable energy sources, and a reduction in electricity consumption.
How to make the construction sector more sustainable?
One way to continue to improve the sustainability of buildings is to also reduce the impact of building materials. The current strategy is aimed at reducing the energy of production processes and using more sustainable materials such as those proposed by the Catalan research group. These materials include renewable raw materials, recycled or from the re-evaluation of waste. The latter option allows waste to be reprocessed. This allows the environmental benefits to be multiplied.
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