I need to ask about covering previous damp patches with paint. We have a couple of patches that were once prone to condensation and where new plaster is not drying properly in our new kitchen – they are not wet, just more unsightly due to condensation point. I need to point out that the unsightly patches seem to be not a result from lots of penetrating damp.
I have read about Polycell damp sealer paint and it seems that this can be applied to dampish areas before applying an emulsion layer – any other suggestions will be greatly appreciated. Then I have read stories that some emulsion paints can show up the stained areas quite badly but others don't and it seems it comes down to the type of paint (silk, matt), whether it is water-based or oil-based and the manufacturer (we will go for quality, not cheap). it is also for use in the kitchen so obviously there will be steam and moisture in the air.
Can anyone advise on what sort of pain and/or undercoat we will need. one further minor problem is that my wife is quite particular about the colour of the finished walls but I guess we could get colours mixed anyway.
I have just noticed some fine white mould on the exterior wall in the alleyway and now wondering if this has anything to do with the unsightly areas inside – they do seem to mostly be in the same place yet others have no sign inside.
Water stains will almost always bleed through water based paints. An oil based white undercoat which leaves a matt finish can be painted over easily. Alternatively spray THIS on the affected area and it can be emulsioned over in about 5 minutes.
There is a small damp patch in the corner of the kitchen by the door – no problem with guttering or door seals but is about 25cm high by about 20cm wide. It is not damp any more but used to be a site of condensation. Immediately outside this area in the alleyway, there are a few bricks with white mould on them. Another small patch is about 1 metre from the ground and is two circles of about 5cm diameter. Again, not actually wet to the touch but there are bricks immediately behind in the alleyway that have white mould.
i will try thr spary-on damp proof stuff and an oil based paint as an undercoat. I was just worried that any water-based emulsion over the top of the undercoat would bring through the damp patch.