Environmental information
Aluminium is arguably the most environmentally friendly building material. It is the most abundant metal on Earth. After oxygen and silicon, aluminium is the third most common element, making up 8% of the earth's crust. This means, with the fact that aluminium is endlessly recyclable, that supplies of aluminium are effectively inexhaustible.
Aluminium's primary source, bauxite, is mined from reserves close to the earth's surface, so habitat disturbance is temporary. Whilst isolating aluminium from bauxite consumes a large amount of electricity, two-thirds of this is now generated through hydroelectric power thus avoiding any CO2 emission.
Recycling reduces energy consumption by 85-95% in comparison to production from ore. Recycling produces high quality aluminium without loss of properties and there is no requirement to mix recycled metal with 'new' aluminium from ore. Recycling rates for used aluminium products are over 80% in building and over 95% in transport and 30% in packaging. With an ever-increasing proportion of recycled metal in use, aluminium can be accurately described as the ultimate sustainable material.
Non-toxicity means that aluminium is safe for plants, animals and humans.
Aluminium in Building
The physical properties of aluminium make it an ideal material for construction. It is light, strong, durable and requires minimal maintenance.
Light weight means less strain on supporting structures, easier handling and reduced transport costs.
High strength means less mass for a specific performance.
Resistance to corrosion means a longer building life even in aggressive environments. Common industrial pollutants such as ammonia, carbon monoxide and carbon dioxide all have very little effect on aluminium. Aluminium is also excellent to use in coastal and marine environments because the effect of sodium chloride on the metal is minimal.
Formability means that architects have an infinite range of design possibilities. It can be cast, rolled and forged as well as extruded to be formed into an unlimited number of shapes. Extruded sections are particularly well defined with clean edges and fine detailing. It can be curved, tapered, welded and cut to the most challenging and dynamic geometries.
Durability means that buildings have a long life with reduced maintenance requirements.
Non-toxicity means that aluminium is safe for plants, animals and humans.
Like most metals, aluminium does not burn and can be used to help provide fire resistance where appropriate.
Physical properties
Principal amongst aluminium's properties is its low density, and thus its lack of weight. Aluminium is one-third the weight of steel yet when it is alloyed its strength to weight ratio is superior to that of steel.
Other key properties are corrosion resistance and formability. Aluminium has a natural oxide film that provides resistance to corrosion and which reforms itself if damaged.
It is naturally durable and maintains its strength even when very cold.
Environmental considerations highlight other unique benefits of aluminium. It is non-toxic, safe to handle, causes no adverse run-off to groundwater and is endlessly recyclable.
In addition aluminium does not burn, is non-magnetic and has good electrical conductivity.
UK Average Annual Usage of Aluminium in Building Systems
| New build |
Refurbishment |
| 31,000 tonnes |
15,000 tonne |
Recycling
30% of the 1.9 million tonnes of aluminium used in Europe in 1997 came from recycling.
Aluminium used in construction
In the UK, over 150,000 tonnes of aluminium are used by the building and construction industry each year, a large proportion of which is in the form of extruded and rolled products
