The future lies in green performance
According to Martin Clarke, the biggest challenge for the industry in the current recession is to maintain and improve on current high standards for environmental management, and health and safety. “A better sustainability record enhances profit performance. The green companies will most likely live through the recession, not only because they are green, but because they are the most efficient ones.” Although the whole construction market is depressed, the market for sustainable construction is growing, and the market share of the companies with a good sustainability profile is going up. In Britain the sustainability of the industry is supported by a brand new scheme for responsibly sourced construction materials BES6001 issued by the BRE. It covers both up and downstream production. The concrete industry published sector guidance last December, and the first certificate for concrete products was granted in March 2009 to Aggregate Industries, part of the Holcim Group.
The three segmetns of sustainability
The key areas that make a building green are the manufacturing supply chain, the energy efficiency of the performance of the building, its maintenance, and its end-of-life performance. In the UK, the precast concrete industry has been mainly addressing environmental issues upstream from the construction phase: that is the materials used, the products manufactured, and the energy efficiency of the factory. “Probably we have not done enough to improve the performance in the use – and the end use – of the building. We should also focus more on the design of deconstruction, and the future re-use and recycling of the materials. And we have done even less in terms of how the buildings are designed for optimum environmental performance,” Clarke admits. “We employ architects in making the product fit for purpose, but we don’t normally get intimately involved with the optimization of design. It’s probably in this area where we have the most to do.”
Precast concrete element is a great product platform: the industry has been working hard on minimizing waste in the factory, including wasted materials and wasted energy. Now it needs to minimize the amount of energy used during the lifetime of buildings and to maximize the flexibility of structures and their ability to respond to global warming. Clarke says that Southern European designs are beginning to be applied in Central and Northern European projects in anticipation of ever hotter summer temperatures. This, of course, is good for precast concrete. “We should continue to cooperate closely with designers, but we should also be more involved with facilities management teams in order to create a better working environment, in particular for office and retail workers. We need to ensure the delivery of fresh air, for example. Precast concrete can play a major role by building intelligence and systems into our designs,” Clarke states. “We can reduce the strain on eyes by using white concrete to improve internal lighting. And we need to be aware of formaldehyde and other emissions that can come out of construction materials as well as office furnishings. Most people agree that precast concrete is a benign building material.” The advantages of concrete really shine when looking at the life-cycle performance. A well made and appropriately designed concrete building will last almost an infinite length of time, providing there are no major changes – for example in its use and loadings. “We can also contribute greatly to environmental performance and our carbon footprint by improving efficiency in the use of Portland cement. We should move away from prescription standards to performance standards for concrete where we can - without compromising the reliability and safety of the building. We are already making great progress in precast in using CEM2 and mixing in supplies of fly ash and slag cement, and the use of the great admixtures that are now available."
Added green value
Clarke calls for electronic technologies that would add value to the buildings made of precast, and which would make the concrete elements easier to maintain and recycle. “In my dreams a precast element going into a building would have its own history embedded into it. If it would become overstressed because of an accident or overload, it would automatically warn the facilities manager. Another future possibility would be new jointing and coupling systems that would better allow releasing, taking apart and reusing the precast elements.” Technologies like these add to the sustainability of the precast concrete, but might also change the way buildings are procured. “Instead of selling the precast concrete once, we might be able to rent or lease it, and get a rental stream coming in for its lifetime, in return for the provision of support and service,” envisions Clarke. “We know how to make precast concrete and we can predict its behavior, so we should focus much more on the added value that we can get out of it. That is where the profit is going to be made.” Caption: Martin Clarke predicts that precast concrete has a really exciting future. “We’ve got the best product, which is a green product, and we have the potential to add even more sustainability to it.”
is Chief Executive of British Precast, the trade federation for concrete products in the UK. He is mentor to the UK Concrete industry Sustainable Construction Forum and is Chairman of the Modern Masonry Alliance. He worked for ARC, now Hanson, from 1972 to 1990 before joining the British Cement Association as Director of Market Development. He joined British Precast in 2002. His best day was spent with Oscar Niemeyer in Rio in 1997. He is 58, married to Linda, and has two adult children, Catherine and Thomas. His hobbies are photography, concrete, music, gardening, and more concrete.