I have 2 bedrooms both experiencing slight back mold in the corners of each room - one room at from of houe and other at back. The house is totally rendered and the both walls in the back room are experiencing salt wet and marks from corners outwards. My 4 yr old sleeps in this room and always sems to have a cough. any suggestions greatly appreciated. :?
You have to find out whether the problem is rising damp or condensation. You say the dampness is in the corners, so it may be you have furniture of some sort in the corner of the rooms affected. If so and the black mould patches are behind the furniture it could be condensation as this can seriously affect the flow of air and condensation will always occur first on the coldest wall, usually north facing. If this is the case you should try to reposition the furniture or at least pull it back from the wall a little to allow the air to circulate. Then you have to deal with the mould which should be treated with an anti fungi wash solution obtainable from places such as B@Q's Homebase etc. Having done that reline the wall first with polystyrene or similiar before re-decorating.
If this doesn't resolve the problem, bearing in mind if you put the furniture back in the same place it will re-occur, then you really need to get a dampness check from a surveyor with a damp meter before you will really know for sure. If it rising damp you will have to get a professional company to carry out the necessary works to the damp proof course.
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