On the road to sustainability
When David Morley and his merry men moseyed into town, it was time for the latest in the Corus-sponsored series of sustainability roadshows. Paul Finch reports
It is probably the closest thing I will experience to a rock and roll lifestyle: chairing a series of sustainability roadshows around Britain and Ireland on behalf of Corus and the AJ. That is to say, those parts of the lifestyle which involve repetition of content in front of different audiences and staying in hotels.
The purpose of the half-dozen evenings was simple: to offer observations on the nature of sustainable architecture and construction, to introduce research work by Corus in relation to a range of its cladding products, and to give an architect's perspective on how an interest in low-energy design can produce a range of fine buildings.
Our 'band' line-up was Michael Sansom from the Steel Construction Institute, Rod Rice from Corus, and David Morley of David Morley Architects.
Sansom was always first up, beginning with a quick reminder on where government policy is taking us regarding sustainability: not just prudent use of natural resources and effective protection of the environment, but an underlying ambition in respect of social progress, and 'high and stable levels of economic growth and employment'. That is to say, sustainability within the context of a modern economy rather than back-to-the-land zealotry.
For those who wanted to be frightened by graphs, here they were: world population growth (the best we can hope for is that the near vertical rise in growth over the last century plateaus out to produce a classic 'S-curve'); biologically productive areas, exploited on the basis of current western consumption levels, suggest we need a planet three times the size of the one we've got (ecological foot-printing). Global warming is, of course, a matter of some near-philosophical dispute, but at least we can agree on what temperatures have been doing recently, and what they will imply for millions of people if very modest average increases continue on the current trend. Oh, and 89 per cent (honestly) of our energy is still supplied by the burning of fossil fuels.
What does this mean for construction?
Sansom first suggested why the sector is important: it represents 8 per cent of UK GDP, employs 1.4 million people, has a predicted growth rate of 5 per cent in the decade to 2012, and of course provides the envelopes in which we spend 90 per cent of our lives.
From the viewpoint of the Department of Trade and Industry, sustainable construction makes good business sense, and it has laid down a series of themes for sustainable construction, including designing for minimum waste, preservation and enhancement of biodiversity, conservation of water resources and minimisation of energy in use.
These aspirations are being tackled partly through Building Regulations and fiscal measures (eg the 2001 climate change levy);
and on a European scale by directives on landfill, packaging waste, construction products and energy performance of buildings.
Energy and onwards A useful reminder of where we stand on energy policy was concisely covered: 10 per cent of UK energy is used in production of construction materials, and 50 per cent in the operational use of buildings. Sansom made the point that the ratio of embodied to operational energy use is 1:8.
This is a fundamental point in current UK national energy policies: 60 per cent reduction in CO 2emissions by 2050; 50 per cent savings achieved through energy efficiency; certification of buildings; and regular inspections of HVAC systems.
A run through the use of steel in construction included the fundamental point that this metal is 'the world's most recycled material' - not surprising given its long history of reuse, the local and global markets in scrap, and the fact that melting down and reuse involves no change in inherent properties. Some 354 million tonnes are recycled annually, of which 10 per cent is reused without a visit to the arc furnace.
This was a suitable link for Rod Rice, who presented the Corus 'Insite' programme on environmental impact of steel products via a case study on life-cycle assessment covering the entire supply chain. The study was in 2roof, assuming a building life of 40 years and end-of-life recycling. Three products were compared: Corus HPS200, and PUR and PE equivalents, and assessed for global warming, resource depletion, photochemical oxidant formation, acidification and eutrophication.
Further studies showed life-cycle cost analysis of a mixture of roofing materials, thermally efficient cladding, and innovation.
Refreshingly, Rice did not pretend that steel was always the best option for every situation, but presented its virtues in the round.
Moving towards the 'delight' part of the evening, we then heard about the Corus 'Repertoire' colour programme, which allows pretty much any colour a designer may want for steel roofing and cladding, available to view on screen with automatic samples produced by electronic order. The Celestia metallic-finish colour range was outlined, developed in conjunction with Tom Porter of Oxford Brookes, and ambitious in terms of its 21-year guarantee. The same might be said in a different context of the 'Assure' product, developed to incorporate 'Microban' antibacterial protection - highly useful in food processing plants, for example.
A Morley moment A final word on modular construction, and then we were on to the David Morley presentation. Although Morley has designed many buildings in steel, like any good architect he chooses what is appropriate for the purpose.
And ideas about buildings may derive from almost any source.He began his talk by reviewing the design of a spoon by Josef Hoffmann from 1910, which to Morley represented a proposition about evolution (the shape of the 'spoon' part), revolution (the steel technology which gave strength without weight), and balance (the end piece). The entire spoon represented integration of ideas - the basis of the buildings that were to follow. These ranged from a hospital in north London to an Oxford College student block, to the Liverpool Biosciences Centre now nearing completion, with a wealth of buildings and projects in between.
His fundamental proposition about energy design related to the way in which 'conventional' buildings generally use onethird of their energy for heating, one-third for cooling and one-third for lighting.
Designs which therefore increased natural lighting and were designed through materials and orientation to hold or repel heat ought, he suggested, to be capable of cutting the energy requirement by 50 per cent.
A fascinating example was the much-celebrated indoor cricket school at Lord's, where an initial request for a black-box facility was amended by Morley to use diffused light in a way that he has been able to modify and exploit in other projects. He has rewritten the rules about indoor sports centres of all descriptions, produced lovely buildings, and slashed energy costs.
Sports buildings with natural lighting and long roof structures lend themselves to the inherent advantages of steel structures, but the principles on display worked well for other building types. A school building exploited clear double-glazed rooflights, with the other part of the modified 'sawtooth' covered in thin-film photovoltaic tiles - 10 square metres provide enough electricity for one classroom. A residential project next to an elevated mainline railway also used PVs for the entire roof, above a highly insulated envelope with glass louvres on the non-rail side; the scheme incorporating heat-recovery units above 'service zone' kitchens and bathrooms. The scheme could not be funded unless the cost of the PVs was drastically reduced.Why aren't PVs subsidised?
In the Liverpool Biosciences Centre project, Morley seemed able to combine his ideas about energy design with construction principles of speed and repetition.
Questions and comments differed at our various locations, but there were some common themes. For example, the importance of location in the overall analysis of energy cost:
an exemplary green building complex which can only be reached by car is a hopeless environmental case. Another simple point: the embodied energy of timber is a lot less than steel. So it is, though the importance of energy use was much more significant; there was desire for more information from Corus, not just about steel, but about its virtues in relation to other products (actually, the BRE guide on the environmental performance of materials does a fair bit of this).
I reminded audiences of the first-rate work undertaken by the RIBA 30 years ago on the subject of energy-conscious buildings, under the aegis of then-president Alex Gordon.
The report, Long life, Loose Fit, Low Energy, is surely worth revisiting and updating as appropriate. An understanding of the virtues of longevity (what about Stewart Brand's How Buildings Learn? ) is as good a starting point for an attitude to sustainability as any (it might encourage government to subsidise PVs). And steel, of course, is a very long-life material indeed.