Barrie Evans is right ('The Greening of steel', aj 9.4.98) to advocate a comparative appraisal of steel, concrete, timber and masonry construction. The steel-versus-concrete debate rather polarises what is a complex picture and, as most designers know, materials are chosen for primary and secondary benefits (practical, environment and aesthetic). What was gained from the Orlando conference was the advantage of composite construction - of valuing mongrels over thoroughbreds - itself a good ecological principle. Steel and concrete can co-exist, and there is a place also for brick and timber. Doxford Business Park in Sunderland is a good example.
The greening of construction is also about more than the relative energy costs of materials. Embodied and in-use energy equations are useful but other resources need to be considered. What about water, which is fast becoming tomorrow's oil? Buildings are responsible for half of all uk water use (just like energy) and water pollution is a major by-product of the manufacture of construction materials. The models we are developing for energy could be applied to water - then we will have genuinely useful models of life cycle assessment.
University of Huddersfield