In article , John Laird
wrote:
However the nice new extension that you get built will have to
comply with building regs and will have a good deep foundation.
Then you are bound to get cracking cos the two bits of houses
will have differential movement

Don't follow this - if the existing structure is presumed not to
be going anywhere anymore, and the extension has foundations
sufficient to stop it also going anywhere, then the two are going
nowhere together, no ?

It's more likely to be the other way round. The extension, on 2004
foundations, will settle a little then stop. Meanwhile if the
existing house is on shallow foundations on shrinkable clay it will
move up and down over the seasons as it has done for 100 years.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
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