We have patches of white spores forming on a kitchen (exterior) wall. They are appearing in sections where the paint has bubbled up (almost blister-like). The pattern is similar to a snail's trail. They can be wiped clear, but then reappear.
The section of wall is between our back door and the kitchen window, which has a radiator underneath it.
Does this sound like condensation? (incidentally the kitchen widow is largely condensation-free).
Any thoughts/tips gratefully received!