We’ve been having some trouble with brown spots on a (freshly) painted wall.
- Moved in a few months ago and had decorator repaint guest bedroom (Dulux primer then Leylands trade waterbased emulsion)
- Brown spots and damp started to emerge in the corner of the room - this wall/arch faces the outside. Had a roofer treat the outside wall to make sure no water leaks through.
- Treated stains on inside wall with Zinsser stain blocker spray. Stains are gone but stain blocker is visible.
- Few hours after fully dried, a new coat of the water based emulsion was applied. Shortly after, brown spots started to emerge again? They appear randomly and not consistently, have attached some pictures.
Possible explanations that I have come up with:
- Outside wall was treated poorly and root cause has not been fixed. Less likely in my opinion because it hasn’t rained in over a week.
- Wall emulsion doesn’t react well with Zinsser stain blocker and causes paint bleed? Not sure how likely this is because the spots emerged at placed where I didn’t use the Zinsser.
- Underlying plaster is damaged/wet/has mould?
- Repaint entire wall with non-permeable and stain blocking paint. Possibly the Zinsser spray was not enough.
Any thoughts, ideas and tips would be greatly appreciated. I am not sure how best to proceed or what the actual issue is.
Also note: I’m an amateur and not a professional.