In article , Simon wrote:
an anyone give some historical details of when/where etc. houses
started to be built with cavities in party walls in British
terrace/semi houses ?

In my former BCO patch of New Malden, SW London, we did find
a late Victorian cottage with cavity walls and flat iron ties,
but most spec builders will still using 9" external walls
throughout the 1930's. Party walls though were almost invariably
9". In my BCO days (1976-84) party walls were sometimes solid,
sometimes cavity: both complied.

Also, is a modern party wall much more sound proofing that the 9"
brick ?

Workmanship has far more to do with it, also whether or not the
wall is wet plastered.

If so, this could be a factor in future home purchases.
Unfortunately you cannot tell how well the wall has actually been
built. Some of the 30s walls are very dodgy when you remove the
plaster, since they were never intented to be seen.

I've told the story about the house built of 1/2 bricks. For a party wall
the vital thing is that the mortar joints are properly filled so that
there are no air leakage paths.

Check out the ODPM website for the current regs (tightened up because
of perceived failings in this area)

http://www.odpm.gov.uk/stellent/grou...ge/br0046.hcsp

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