In article ,
Tony Bryer writes:
On 08 Jan 2008 23:01:14 GMT Andrew Gabriel wrote :
Yes -- until about 1970, houses in the UK were built with a
life expectancy of about 200 years.

A bit optimistic, I think: without any evidence I would have
thought that the majority of pre-1880s properties have long since
been demolished.

Yes, but mostly through social engineering, not contruction
failures (although there are some I'm sure).

From that point, a wide
diversity of construction changes has appeared, which is
likely to lead to a number of shorter lived houses. As a
surveyor pointed out to me, this isn't something the public
have taken on board yet when considering the value of a
property, which means many houses are built using cheaper
shorter life materials in the knowledge they will still
sell for the full price.

What's happened since 1970 is the price of land has escalated
dramatically as has the cost of repairs and maintenance, new build
- which has been deskilled - less so. Thus knocking down a 1930s
house and building a new one to modern tastes and needs may make
economic sense, which would not have been the case a few decades
back. If the house is listed or in a Conservation Area it may well
sell for less than the cleared site value - IOW the building has a
negative value.

That's an argument for not bothering to design houses to
last 200 years, as other factors will render them obsolete
before then.

--
Andrew Gabriel
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