6 min read
Learning how to prepare walls for painting is the difference between a room that looks sharp for years and one that shows every flaw the moment the light hits it. In Dublin homes we spend roughly two thirds of interior painting time on preparation and one third applying paint, and this is the sequence we follow on every job from a single bedroom to a full house.
Clean before you fill
Walls collect cooking grease, hand marks, dust and, in older houses, nicotine. Filling and painting over that traps the contamination under the new coat, and it eventually bleeds or causes adhesion failure. We wash with sugar soap, rinse, and let the wall dry fully before anything else happens.
Fill, caulk, sand — in that order
Cracks and holes get filled proud and sanded flush; deep holes are filled in two passes so the filler does not sink. Caulk goes into the junctions — skirting to wall, architrave to wall, coving lines — because those shadow gaps are what make a decorated room look unfinished. Then everything is sanded and dusted off.
Sanding is not optional on previously glossed woodwork or on shiny old emulsion. Fresh paint needs a key to grip, and thirty minutes of abrasive work prevents a coat that peels off with the masking tape.
- —Sugar soap wash and rinse
- —Fill cracks and holes, two passes on deep ones
- —Caulk all junctions and shadow gaps
- —Sand flush and remove all dust
- —Spot-prime filler, bare plaster and stains
Prime and stain-block the right places
Filler and bare plaster absorb differently to painted wall, so they flash through the topcoat unless they are primed. Water marks, smoke damage and marker pen need a dedicated stain-blocker — emulsion, however many coats, will not hold them back. New plaster needs a thinned mist coat first so the finish coats bond instead of peeling.
Frequently asked questions
- Do I need to remove wallpaper before painting?
- In almost all cases yes. Painting over paper looks acceptable at first, then seams lift and bubbles form as the emulsion wets the paste. Stripping, washing off the residue and repairing the plaster is the durable route.
- How long should filler dry before painting?
- Follow the product, but deep fills need longer than the tub says. If filler is still cool to the touch it holds moisture and will flash through the topcoat.