plaster over kitchen sink

[Emil Sjögren]

Anyone know if it works with gypsum plaster over/behind the sink? I'm thinking of plastering and then painting with some sensible paint that is somewhat water-repellent. Or does the plaster need to breathe? Today there's just a standing plank wall behind, quite sparse... Anyone who has an idea of a sensible material to apply the plaster on? Masonite? Renovation plasterboard??

 

[MaxPax]

My immediate thought is that plaster is directly unsuitable there because that plaster does not tolerate moisture. Even if you encapsulate everything with some waterproof paint, it is very likely that a little will seep in anyway.