I grabbed these photos from the internet for a family that has a house that is affected by mould.
Due to housing shortages they have been told they have to stay put for the time being.
There are a few pictures of the house where the mould continues to form on the walls that they continue to clean without actually stopping the problem.
There must be a rising damp problem somewhere but what is missing from this house from houses in the past is there is no ventilation panels in walls these days aside from external weep holes. Perhaps part of solving this problem is to reintroduce ventilation panels?
Could this simple modification speed up drying up the wall cavities as well as drainage piping/gravel around the external perimeter of the property?
And/or adding webbing to the flooring if there is rising damp issue and managing this by putting a barrier on top of the concrete slab tinside the house?
Have added a few of the pictures below