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clot

wrote:
On 13 Mar, 13:49, "Mary Fisher" wrote:
"Tony" wrote in message

o.uk...

Hi,
Thanks for the replies.
The house has a cavity but I have been cautioned against getting
cavity insulation as it alows moisture to bridge from the stone
layer through to the inner brickwork.

Who told you that?

We've had it for years and hzve been 100% satisfied with it on all
counts.

Mary

Dear All
It all depends on the insulation! The whole idea and purpose of the
cavity is to prevent water going from outer to inner leaf. So.....any
form of insulation that bridges this permanently in such a manner that
water can get thru is not appropriate. Ideally, as with most building
alterations, it is best to be reversible i.e. you can suck out the
insulation as in beading or rockwool blown fibres etc as opposed to PU
foam or the like which sets and that is it!
In other words - chose the right product and application method and
its fine to do

I share your concern. In our previous house, I had blown in mica which did
not cause a problem. Our current house which had blown in rockwool from new
did have problems with bridging, but whether that was due to initial
construction I'm unsure (was not able to be about when the issues were
resolved). The issue to me with blown in stuff is the collapse that occurs
when one wishes to make adjustments such as putting in a vent for a clothes
dryer or new gas boiler.