Learning from longevity.

When architects design buildings, how often is duration an explicit part of the programme? This is a grey area largely avoided by clients and designers. And it is true that longevity will depend to a large extent on maintenance regimes, and long-term beneficial occupation. Unless there is certainty about these factors, is there any point in worrying about the future? The answer must now be a resounding 'yes'. There is increasing concern about the use of resources in respect of natural and manmade environments, and a concomitant desire to minimise waste, in terms of energy and materials, in both construction and subsequent use. The inevitable creation of new buildings in a healthy economy makes the exploitation of existing resources of more than passing interest. As we have argued here before, the idea that a building should have a first use and then be demolished to make way for the next big fashion is offensive. It is absolutely at odds with architectural thinking interested in doing more with less (or with the same). On this basis, demolition should be, if not the last resort, at least a conclusion reached only after thoroughly analysing the possibilities of refurbishment, extendability, or giving new life based on a different sort of use.

We can apply to new architecture the lessons we have learned about buildings that are incapable of lasting more than thirty or forty years. Those lessons should inform what we create today; certain buildings (for example Germany's Federal Environment Agency headquarters in Dessau, AR July 2005) can become exemplars of what we should expect, albeit in dilute form, from any significant new building or collection of buildings. Another example, the Richard Rogers Partnership National Assembly for Wales, featured in this issue, has been designed to have a minimum life of one hundred years. A question that arises from such a programme is whether we should be creating any new buildings without such a life expectancy; and were we to adopt such a strategy, what would be the architectural and specification consequences? The answers might form the basis of more intelligent regulatory regimes for buildings than the usual mish-mash of outdated and uncoordinated rules.

Elsewhere in this issue, we review buildings that have found welcome new leases of life in one way or another. Architectural ingenuity in knitting together past and present shows no sign of diminishing and, in some way, is increasing as a result of stricter requirements from those interested in conservation and heritage protection. It is a great pity that an antipathy to new architecture has too often informed conservationist ideology. A fundamental case for respecting any existing heritage concerns the intellectual, physical and economic investment already made in it; this is nothing to do with what the building or area looks like. Rem Koolhaas has recently made the case for protecting 'hutongs' in Chinese cities rather than pursuing a policy of careless demolition and compulsory export of their communities to sites that are miles away, and comprise dumb high-rise blocks that tenth-rate Modernism gave the world. Understanding the past, and paying it the compliment of appropriate technical upgrades, can perfectly happily sit alongside a vibrant programme of new architecture and construction designed to last. Respect is not a synonym for sentimentality.