Surprise cavity wall!

Our house was built sometime between 1910 & 1920. It has had multiple extensions since the 1960s all of the extensions have cavity wall insulation fitted. I’ve always been advised that the walls of the original house don’t have a cavity. i.e. That there are two brick walls but with almost no cavity gap between them.

We’re currently having new windows installed and have found that for some reason the front wall of the house does have a 6cm cavity whereas the rear wall as expected is less than 1cm.

So I’m thinking that we should get the cavity in the front wall insulated. I presume the only option will be to blow some sort of insulation in from the top or bottom.

Does anyone have any recommendations of the best type of insulation to use, or of good contractors to use in South Manchester.



My “solid” walled house also has a partial cavity in places but it is not contiguous. This presents a problem with blown insulation.

Notwithstanding the above, any insulation needs to be free draining and vapour permeable, otherwise you risk causing damp in the inner leaf.