Nick Cowley, Managing Director at Endurawood, explains why aluminium plays an important role in making the construction industry more sustainable.
Innovation organisation InnovateUK states that construction, operation and maintenance of the built environment account for 45% of total UK carbon emissions. By 2031, it is predicted that the United Kingdom’s population will exceed 70 million. With a rising population, and an increasing need for buildings and homes, it is imperative that the industry takes action to reduce its carbon emissions.
Concrete is the most common man-made material on earth, used in a variety of construction applications including interior and exterior cladding, but it is also responsible for up to 8% of the world’s carbon dioxide (CO2) emissions — only coal, oil and gas are greater sources of greenhouse gases.
The majority of CO2 emissions are produced during the making of cement clinker, a nodular material that is produced by heating ground limestone and clay at a temperature of up to 1,500°C. These nodules are then ground up to a fine powder to produce cement.
Conversely, aluminium has a much lower environmental impact and possesses many benefits that make it an ideal building material. Its high ductility allows it to be shaped into many different way without weakening. Furthermore, aluminium is nearly as strong as steel while being lighter, which makes it more manageable on site. Compared to other metals, aluminium is corrosion-resistant as its surface is naturally protected by a layer of aluminium oxide — reducing the frequency of maintenance on a building.
From an environmental perspective, perhaps the most significant benefit of using aluminium lies with its recyclable and sustainable possibilities. Although there are sustainable options such as timber, straw and compressed earth, that can be used in the construction industry, these materials do not offer the required strength needed for a buildings structure.
Although 40% of the UK’s annual aluminium production is used in the construction industry, the equivalent of 150,000 tonnes, steel is still the most used metal.
Like all metals though, aluminium production is not a hazard-free process. Aluminium is chemically extracted from bauxite, an ore that must be mined. This is known as alumina, which is then smelted to form pure aluminium. While aluminium production is still impactful on the environment, these effects can be mitigated by the metal’s recycling potential.
It is thought that around 75% of all aluminium produced remains in circulation, in some form or another. Aluminium can be melted and reused without any impact on its mechanical properties. This means that aluminium products can be manufactured over and over again to the same high standard.
The benefits of aluminium make it an ideal building material as it can be applied to different areas of a build, including roofing, wall panels, windows and doors. It can also be used as an alternative material to replace concrete and timber exterior cladding and batten systems, which can be used to enhance the appearance of a building, as well as for structural reinforcement.
Lastly, although aluminium is highly durable, when it is time to replace the cladding and battens, they can be recycled and reused for another building product — ensuring minimal waste.
While there are a number of steps that must be taken to achieve Net Zero emissions in the construction industry, considering a material such as aluminium could make a significant impact. If the industry wants to reduce its carbon footprint, harnessing the benefits of a lighter weight, sustainable material could help to make this possible.