there are some spots, like where an old chimney ran, which just don't clean
could this be because the brick is actually burnt there? rather than having burnt stuff stuck to it.
Probably.
There was a lot of belly scratching from the stone mason at the time saying none of it would come out and they should plasterboard. But in the end most if it came clean and the bits that didn't just looked characterful.
@hugo7 started
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could this be because the brick is actually burnt there? rather than having burnt stuff stuck to it.