Nothing is more frustrating than repairing a damp wall, repainting it, and then seeing a patch reappear or look different from the rest of the room.
First step: fix the source, not just the symptom. If the leak from a pipe, terrace, or neighbour’s bathroom isn’t properly resolved, any repainting is just temporary makeup.
Once the wall is dry (properly dry, not just “looks dry”), scrape off loose paint, bubbling areas, and damaged plaster if needed. Sometimes, the affected area needs fresh plaster, not just putty.
Use a good quality primer, ideally one made for stain blocking or damp-treated areas. This helps prevent previous stains from bleeding through your new paint.
When repainting, feather the paint out beyond just the patch area—cover the whole wall or at least a wide section. Painting only a tight square makes the difference more obvious.
If your last paint job is old and faded, a full-room repaint might be the only way to truly blend everything.