Consider opening up the area around the house to improve air flow and sunlight. The restriction/obstruction of one or both of these 'natural things' promotes the growth of mold and mildew.
I agree w/Steve: Have the walls washed w/a fan-tipped washer. Brick and morter that's 60+ years old could be easily loosened by too much water pressure coming out of the nozzle.
My best to ya and hope this helps.
Jay J -Moderator
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