I kept noticing these formations on the rising damp of the kitchen wall after the flood. I searched 'white mould on damp wall'.
I was surprised when I read a possible explanation :
In chemistry, efflorescence (which means "to flower out" in French) is the migration of a salt to the surface of a porous material, where it forms a coating. The essential process involves the dissolving of an internally held salt in water, or occasionally in another solvent. The water, with the salt now held in solution, migrates to the surface, then evaporates, leaving a coating of the salt.
Source
My photos were not that clear this evening. I will try to take more photos during the day and see how much it expands. It is definitely worrying and unsightly to see it, but at least it's not mould... we've got enough of that to deal with elsewhere.
Of course I also looked at whether one could eradicate it completely. I found this website where it says that waterproofing is really the answer, but you can also just :
brush off the salt from the surface. Depending on the amount of salt, it can sometimes be done with an old paint brush or it may require a stiff scrub brush.
We're not builders or house DIYers so that it's probably the option we'll take; I'll just hoover it until the wall dries up enough and then we'll paint over it.
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