5 min read
Ceiling painting looks like the simplest part of a decorating job until a water stain reappears through three coats of brilliant white. In Dublin houses, old leaks, bathroom overflows and chimney staining are extremely common, and no amount of emulsion will hold them back — stain blocking is a separate step with a separate product.
Why emulsion never covers a water stain
Water marks contain soluble salts and tannins. Water-based emulsion re-dissolves them, and they wick straight up through the wet film — sometimes immediately, sometimes weeks later. A dedicated stain-blocking primer forms a barrier the stain cannot travel through. One coat of blocker beats five coats of emulsion every time.
- —Fix the leak first and let the ceiling dry
- —Apply a proper stain-blocking primer to the affected area
- —Then two full coats of ceiling emulsion across the whole ceiling
- —Never spot-paint a ceiling — it always shows
Whole ceilings, not patches
Even with a perfect colour match, a patch on a ceiling shows as a different sheen under daylight. Once a ceiling needs attention it is painted corner to corner. It is also the reason we cut in and roll in a consistent direction and keep a wet edge — a ceiling shows lap marks more than any wall.
Artex, cracks and older Dublin ceilings
Many Dublin ceilings from the 1970s and 80s carry textured artex. It can be painted as it is, skimmed flat by a plasterer, or filled and smoothed where the texture is light. Cracks along the wall-ceiling junction are usually movement rather than damage and are best caulked rather than rigidly filled, so they do not simply reopen.
Frequently asked questions
- Can you paint over a water stain without fixing the leak?
- You can block it cosmetically, but if the leak is live it will return and the plaster may fail. We always advise fixing the source first.
- Do ceilings need two coats?
- Yes, in nearly all cases. One coat over old emulsion looks patchy under daylight, especially in rooms with a window on one side only.