| Concrete has traditionally endured a poor reputation | | | | commonplace. The material offers flexibility and |
| as a fundamental building material due to perceptions | | | | seemingly redundant concrete structures can be |
| concerning its reliance on virgin raw materials and the | | | | worked on, redesigned and rebuilt with new |
| energy consumption and emissions associated with its | | | | up-to-date specifications. However, if demolished, the |
| production process. Based on recent developments, | | | | resulting aggregate can also be used for a number of |
| CEMEX UK’s Technical Director, Steve Crompton, | | | | applications as a ready-made and important recycled |
| argues that concrete should, instead, be viewed as a | | | | material. |
| sustainable, strong, long-lasting, versatile and | | | | Contrary to popular belief, all rubble does not end up |
| economically important construction material that has | | | | in landfill after a building’s demolition. Anything up |
| a vital part to play in the UK’s development of | | | | to 95 per cent of a building’s components can in |
| more sustainable communities. | | | | fact be recycled, including the most heavily reinforced |
| Concrete is the most widely used construction | | | | concrete. |
| material in the world. It is all around us; from offices | | | | Indeed, recycled concrete aggregates (RCA) has |
| to schools, roads to railways and dams to homes. Its | | | | proven performance characteristics and is being used |
| powerful economic sway sees over 40,000 people | | | | in the ongoing production of new concrete – thus |
| directly employed in its UK manufacture, and it | | | | completing its life circle. New European Standards |
| supports a construction industry employing seven per | | | | have cleared the way for greater use of recycled |
| cent of our population. However, when it comes to | | | | concrete aggregates in the manufacturing process, |
| considering its sustainable credentials, which will | | | | supporting UK Government targets of increasingly |
| ensure that we balance our current rate of | | | | meeting construction demand with material from |
| development with the resource requirements of | | | | secondary and recycled sources. |
| future generations, it is important to look at | | | | From an economic point of view, concrete and its |
| ready-mix concrete from several angles: its | | | | sustainable credentials are well matched. To improve |
| environmental and lifecycle aspects, its economic | | | | their sustainability credentials, products should be |
| impact and its contribution to our society in general. | | | | consumed as near to the place of production as |
| Taking the environmental aspect first. There is clear | | | | possible. This country’s self sufficiency in |
| evidence that improvements in environmental | | | | providing the core materials required for concrete |
| performance are underway to minimise the impact of | | | | production means that inbound raw material transport |
| concrete production. These changes include actively | | | | and import levels are kept to a minimum. More often |
| reducing the emissions associated with the concrete | | | | than not, the concrete industry uses locally sourced |
| manufacturing process, and lower the reliance on | | | | materials for local construction projects, thereby |
| virgin raw materials by increasing the use of | | | | minimising transport related impacts. Compare this to |
| by-products in concrete. Add in better management | | | | timber, which imports over 98 per cent of the total |
| of waste, the use of more recycled aggregates and | | | | volume used in UK construction. |
| alternative fuels, as well as the thermal mass of | | | | With increased pressure on conserving fossil fuels, |
| concrete, which in the face of climate change, can | | | | such as coal, for future generations, rising energy |
| help keep future housing cooler in summer than | | | | costs and changes to our climate, concrete can |
| lightweight houses, whilst also saving heating fuel in | | | | contribute positively by offsetting the heating up of |
| winter, it is clear that concrete has a fundamental | | | | buildings (especially in summer). Concrete’s high |
| part to play in helping to deliver the energy efficient | | | | thermal mass can help absorb the heat generated by |
| buildings of the future. | | | | people, computers, lighting and electrical equipment, |
| While total construction industry impact accounts for | | | | and keep internal temperatures lower. |
| 10 per cent of total UK CO2 emissions, concrete is | | | | The thermal mass in concrete walls and floors stores |
| responsible for just 2.6 per cent of this. Compared to | | | | energy from the sun and the building’s own |
| the 33 per cent generated by transport, this is a | | | | heating system, and releases this at night, thereby |
| relatively small amount, especially considering its | | | | sustaining warmer overnight temperatures and |
| importance as a basic construction material. Concrete | | | | reducing the need for heating. |
| also comes out favourably when compared to | | | | Finally, from an economic standpoint, as a |
| structural steel, where the amount of CO2 generated | | | | self-sufficient producer of this material and a UK net |
| per tonne is approximately 10 times greater than that | | | | exporter of concrete and component materials, |
| of reinforced concrete. | | | | concrete more than holds its own against other |
| The use of waste products from other industries, | | | | important materials. |
| such as ground blast furnace slag or fly ash, either as | | | | Concrete offers many virtues to our society as a |
| a mixer addition or incorporated in factory-blended | | | | whole. It produces natural light when used in exposed |
| cement significantly reduces the overall greenhouse | | | | areas within a structure, and reduces the need for |
| gas emissions, and means that this essential building | | | | artificial lighting. It is naturally inorganic and inert, and |
| material is, and will continue to make, a significant | | | | does not need treatment with additional toxic |
| contribution to the Government’s UK Climate | | | | chemicals. It has inbuilt fire resistance and offers |
| Change Programme of driving down CO2 emissions | | | | secure characteristics due to its strength and |
| by 60 per cent by 2050. | | | | robustness, and will last for a minimum of 60 years |
| In addition to actively consuming waste products | | | | with little or no maintenance. There is no process of |
| from other industries and processes, the industry is | | | | natural decay, which bodes well for future predicted |
| working towards improving production plants and | | | | environmental changes, and as a material for buildings |
| compliance with international standards, such as ISO | | | | is well regarded by designers and the public alike, who |
| 14001, to prevent pollution and ensure continual | | | | according to research, view masonry built houses as |
| improvement through the implementation of | | | | having the longest life expectancy of all construction |
| environmental management systems (EMS). Use of | | | | options. |
| recycled water at production plants is also on the | | | | Sustainability is no longer an issue of choice, but must |
| increase and is increasingly commonplace. | | | | be considered at the very heart of ongoing |
| It’s not only the environmental aspects of | | | | development for our society. Assessing the |
| concrete that should be assessed as sustainable and | | | | sustainable credentials of products is a complex |
| positive, however, so let’s consider its overall | | | | business and must take into consideration their |
| lifecycle. | | | | combined environmental, economic and social impact |
| Like other building materials, concrete has a life span. | | | | and performance. |
| When compared to other commonly used | | | | As illustrated here, concrete is a fundamental building |
| construction materials it is by far the most durable, | | | | material which combined environmental, economic and |
| with a typical design life of at least 60 years. It | | | | social performance is strong. It therefore has a critical |
| essentially has three phases of life. Its creation, its | | | | role to play in delivering more sustainable |
| use in buildings and structures, and its reuse through | | | | communities, by reducing emissions and providing |
| recycling once the building comes to the end of its | | | | long-lasting, secure as well as cost and energy |
| life. | | | | efficient buildings for the future. |
| It is far more likely that a modern concrete building | | | | We in the cement and readymix concrete industries |
| will be deemed obsolete due to no further perceived | | | | are proud of the essential role we have played in |
| usage, than the concrete fabric of the structure | | | | creating Britain’s built environment and are |
| having failed due to age. With this in mind, and with | | | | positive that our industry has a lot more to |
| cost-efficiency and sustainability now to the fore, | | | | contribute in the future to the further development |
| reuse of concrete buildings is ever more | | | | of sustainable building materials. |