--- Met History <[log in to unmask]> wrote:
> On the rare occasions the subject of a building's
> lifespan (which indirectly relates to future
> maintenance) was broached in the architectural &
real
> estate press (1890-1940), it was widely opined that
> steel framed buildings -could- last for a thousand
> years, but that they wouldn't last more than
> thirty, because of economic obsolescence.

So now, after 70-100 years, we have problems with
corrosion of the steelwork causing the masonry to
crack, spall and be displaced, but the heritage
community require the building owners to ignore the
economic obsolescence and spend exorbitant amounts of
money deconstructing, repairing and reconstructing the
facades of these buildings.

Today, we design buildings for a service life of as
little as 20 years, because that is 2-3 times the
length of the financial return period the investors
are interested in, but knowing from our experience
with older buildings that there is a very high
likelihood that the building will still be there in
30-40 years, which means that the next generation will
have enormous maintenance requirements to keep the
building safe and comfortable (let alone looking
reasonable).

So much for sustainability.

Cheers

david

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