Which paint goes over previously painted wood?
Which paint goes over previously painted wood?
Clean it, key it and spot-prime bare areas — and find out first whether the existing paint is oil or water based.
Adhesion failures on repainted joinery come from three causes, in order: grease, gloss and incompatibility. Kitchen and bathroom woodwork carries an invisible film of cooking grease and body oils that no amount of sanding removes, so degreasing with sugar soap or a detergent comes before abrading, not after. Gloss needs a physical key, which means abrading until the shine is gone rather than a token pass. Incompatibility is the sneaky one: modern water-based paint over old oil-based gloss can look perfect and peel off in sheets a year later, and the test is simple — rub a hidden area with methylated spirit on a rag, and if paint comes off on the rag it is water-based. Pre-1990s paintwork should be tested for lead before any sanding.
The options, ranked
| Option | Good at | Bad at |
|---|---|---|
| Water-based acrylic eggshell or satin | Low odour, fast recoat, keeps its colour and does not yellow in dark rooms. | Needs a bonding primer over old oil-based gloss, and it takes weeks to reach full hardness. |
| Oil-based (alkyd) gloss | Flows out to a hard, wipeable film that is still the toughest option on skirting and doors. | Yellows over time, particularly out of daylight, and is slow. |
| Bonding or adhesion primer | The bridge between old oil-based paint and new water-based topcoats. | An extra coat and an extra day. |
| Stripping back | The only real answer where the existing paint is failing, flaking or has too many layers to detail. | Slow, and a lead hazard on older paintwork. |
Technique that changes the outcome
- Wash with sugar soap or detergent, rinse, and let it dry
- Abrade with 120-180 until the whole surface is dull, then dust off
- Spot-prime any bare wood or filler
- Use a bonding primer if going water-based over old oil-based paint
- Test old paintwork for lead before sanding
What goes wrong
- Sanding before degreasing, which grinds the grease into the surface
- Painting over flaking or blistered paint rather than removing it
- Water-based over oil-based gloss with no primer
Compiled practical guidance rather than a published standard. Product formulations vary by brand and market, so read the label — and where the work is structural, electrical or gas, the regulations that apply where you are govern rather than anything here.
Other paint questions
| For | Use |
|---|---|
| Bare wood | Knotting solution on the knots, a wood primer, then your topcoat — and prime end grain twice. |
| Plastic | Any paint, provided an adhesion promoter goes on first — and on polypropylene or polyethylene, the promoter is not optional. |
| Kitchens | A scrubbable acrylic eggshell or satin on the walls — and for cabinets, degrease, prime and use a proper cabinet enamel. |
| Bathrooms | A moisture-resistant acrylic in a satin or eggshell sheen with a mould inhibitor — but ventilation, not paint, is the actual fix. |
| Metal | Remove the rust, apply a rust-inhibiting primer the same day, then an alkyd or a direct-to-metal acrylic. |
| Ceilings | A flat matt emulsion — and if there is a water stain or nicotine, seal it with a shellac-based stain block first. |
| Tiles | Tile paint over an epoxy or adhesion primer on a thoroughly degreased and abraded glaze — and expect a limited life in a shower. |
| Fences | A penetrating stain or fence treatment rather than a film-forming paint — and let new pressure-treated timber weather first. |
| Floors | Two-pack epoxy on concrete after a moisture test and a proper grind; floor-grade varnish or floor paint on timber. |
| Radiators | A radiator enamel — water-based acrylic ones no longer yellow, which ordinary gloss on a hot surface always will. |
| Exterior masonry | A breathable mineral or masonry paint — and on an old solid wall, breathability matters more than any durability claim. |
| Galvanised metal | A mordant wash, a self-etch primer or a purpose-made acrylic primer for galvanising — ordinary oil-based primer peels off in sheets. |
| UPVC | A uPVC-specific paint or an adhesion promoter with an acrylic topcoat — and avoid dark colours, which can distort the frame. |
Common questions
- Which paint goes over previously painted wood?
- Clean it, key it and spot-prime bare areas — and find out first whether the existing paint is oil or water based.
- What should I avoid?
- Sanding before degreasing, which grinds the grease into the surface Painting over flaking or blistered paint rather than removing it Water-based over oil-based gloss with no primer
Related pages
- Which paint should I use on bare wood? Knotting solution on the knots, a wood primer, then your topcoat — and prime end grain twice.
- Which paint sticks to plastic? Any paint, provided an adhesion promoter goes on first — and on polypropylene or polyethylene, the promoter is not optional.
- Which paint should I use in a kitchen? A scrubbable acrylic eggshell or satin on the walls — and for cabinets, degrease, prime and use a proper cabinet enamel.
- Which paint should I use in a bathroom? A moisture-resistant acrylic in a satin or eggshell sheen with a mould inhibitor — but ventilation, not paint, is the actual fix.
- Which paint should I use on metal? Remove the rust, apply a rust-inhibiting primer the same day, then an alkyd or a direct-to-metal acrylic.
- Which paint should I use on a ceiling? A flat matt emulsion — and if there is a water stain or nicotine, seal it with a shellac-based stain block first.
- Which paint can I use on tiles? Tile paint over an epoxy or adhesion primer on a thoroughly degreased and abraded glaze — and expect a limited life in a shower.
- Which paint should I use on a fence? A penetrating stain or fence treatment rather than a film-forming paint — and let new pressure-treated timber weather first.
- Which paint should I use on a floor? Two-pack epoxy on concrete after a moisture test and a proper grind; floor-grade varnish or floor paint on timber.
- Which paint should I use on radiators? A radiator enamel — water-based acrylic ones no longer yellow, which ordinary gloss on a hot surface always will.
Sources
- Typical range compiled from manufacturer specifications — At One Place