Structural strength after dampness

[Ian34]

Anyone know anything about this?
I have had a fairly substantial water leak from a shower pump, unnoticed for a few months probably, in my the base of my airing cupboard (its a bungalow and I thought the water was coming down from the top of the chimney as it has in other properties of a similar design across the road) which used to house the main heating system with a chimney above it.
The dampness has permeated about 3 feet along the base wall blowing the plaster and soaking the wood work around the door frame and skirting.
My main concern is if this may have damaged the structural strength of the base of the chimney as the external part of it is a fair few tons of Purbeck Stone potentially making it top heavy and unstable. Anybodies field?

 

[big-all]

brick stone wood plastic are very unlikley to be affected by damp unless the mortar gets washed out
wood will only rot if the correct moisture level is maintained over a long period off time around 22% i think it is
there is probably a 3% chance off damage that needs repair over 3 months

 

[^woody^]

Walls in the foundations of every building seem to cope OK with being soaked all year round