Painting over the top can work. It can also go very wrong. The difference is almost always prep. Below is a simple guide to help you spot common problems, decide if you can paint over them, and choose the right fix before you open a tin.
If you would rather skip the guesswork, our team can handle it for you. Large offices, clinics, restaurants and roof projects are our daily bread. See how we stage commercial work with minimal disruption on our pages for office and tower painting, medical clinic painting, restaurant painting and roof painting.
Quick checks before any repaint
- Wash the surface with sugar soap and warm water. Rinse and let it dry.
- Do a cross-hatch adhesion test. Lightly score a small grid, press painter’s tape over it, then pull. If paint lifts, you need deeper prep or a bonding primer.
- Know your base. Oil over water and water over oil behave differently. If you are unsure, rub with methylated spirits. If colour transfers, it is likely water based. For a deeper dive, read oil vs water based paints.
1) Glossy enamel and previously oil-based trim
Can you paint over it? Yes, with proper dulling and the right primer.
Fix
- Degrease, then sand to a uniform dull finish with 120 to 180 grit.
- Wipe clean.
- Spot prime bare patches, then use an adhesion primer designed to grip glossy surfaces.
- Topcoat with a hard wearing waterborne enamel for low odour and fast cure.
If you are doing kitchens, also scan common kitchen painting mistakes before you start.
2) Flaking, peeling or blistering paint
Can you paint over it? Not until it is sound.
Fix
- Scrape all loose edges. Feather sand.
- Check for moisture. Roof leaks and bathroom steam are frequent culprits.
- Prime with a sealer that locks down chalk and edges.
- Patch, sand, reprime, then paint.
Repeated failure usually points to moisture or the wrong previous system. If this is external, see best exterior paints for Brisbane homes for systems that survive our sun and storms.
3) Mould and mildew
Can you paint over it? No. Paint will not kill mould.
Fix
- Treat with a mould wash. Rinse and dry fully.
- Improve ventilation.
- Prime with a stain blocking primer if shadowing remains.
- Use a bathroom-grade or scrubbable finish.
For healthcare spaces that need low odour and antimicrobial options, see painting medical clinics.
4) Nicotine, smoke and water stains
Can you paint over it? Only with a proper stain blocker first.
Fix
- Clean thoroughly.
- Seal stains with shellac or dedicated stain blocking primer.
- Two finish coats.
Skipping the blocker causes yellowing to bleed through within days.
5) Chalking exterior paint and oxidised Colorbond
Can you paint over it? Not until the chalk is neutralised.
Fix
- Wet scrub with a stiff brush. Rinse until runoff is clear.
- Allow to dry.
- Apply a chalk-binding sealer where needed, then topcoat with a high UV acrylic.
For roofs, our roof painting process covers cleaning, repairs, priming and heat reflective options suited to Brisbane’s sun.
6) Timber tannin bleed and knots
Can you paint over it? Yes, with the right blocker.
Fix
- Sand smooth and remove dust.
- Spot seal knots and any brown bleed with shellac-based primer.
- Prime all bare timber, then finish coats.
On cabinets and furniture, consider a tougher system. Our cabinet painting page explains two pack and waterborne enamel options.
7) Laminate, melamine and tiles
Can you paint over it? Yes, with bonding products and careful prep.
Fix
- Degrease thoroughly. Scuff sand lightly.
- Use a dedicated adhesion primer for laminates or a tile primer.
- Apply durable topcoats in thin, even layers.
Skipping the primer is the most common reason these jobs fail.
8) Render and masonry with hairline cracks or efflorescence
Can you paint over it? Yes, after you stabilise the surface.
Fix
- Brush off salts. If efflorescence returns after drying, solve moisture ingress first.
- Fill hairline cracks with flexible masonry filler.
- Prime alkaline or fresh render with a masonry sealer.
- Use an exterior acrylic designed for high UV areas.
9) Rusty metal and galvanised steel
Can you paint over it? Yes, once rust is treated and the surface is keyed.
Fix
- Remove loose rust and scale.
- Treat remaining rust with a converter if required.
- Prime bare steel with an anti-corrosive metal primer.
- Galvanised needs an etch or dedicated galvanised primer before topcoating.
10) Grease and steam in kitchens
Can you paint over it? Not until every trace of grease is gone.
Fix
- Degrease twice, rinse and dry.
- Lightly sand to degloss.
- Prime stains where needed.
- Use a scrubbable finish that tolerates frequent cleaning.
For hospitality projects, see restaurant painting for coatings that survive heavy service and clean-downs.
11) Silicone, old sealants and failing caulk
Can you paint over it? Pure silicone, no. Paint will bead off it.
Fix
- Cut out silicone and replace with paintable sealant.
- Allow cure as directed, then paint.
12) Lead paint and unknown old coatings
Can you paint over it? Only with correct containment or encapsulation.
Fix
- Do not dry sand. Use safe methods or call a licensed professional.
- Encapsulation systems exist, but the base must be sound.
If you are preparing a property for sale, this guide on painting before selling covers simple value wins that stay compliant.
Brisbane climate tips that save repaints
- Watch humidity. High humidity slows cure and can trap moisture. Aim for dry, mild days or use after-hours windows with airflow.
- Respect recoat and cure times. Hard wear areas like benchtop edges and doors need a proper cure to resist sticking.
- Specify UV stable systems outdoors. Our sun is unforgiving. If in doubt, start with best paint for commercial properties in Brisbane and best exterior paints for Brisbane homes.
- Plan around service hours. For offices and towers we stage floors and lobbies so tenants keep moving. See office and tower painting for how we schedule.
- Dispose of waste correctly. Leftover tins and wash water need care. Use this local guide to disposing of paint in Brisbane.
Simple product cheat sheet
- Adhesion primers for glossy trim, laminate and tiles.
- Stain blockers for water marks, nicotine and tannin.
- Masonry sealer for fresh render and alkaline surfaces.
- Anti-corrosive metal primers and galvanised etch where needed.
- Waterborne enamels for doors, trims and cabinets where low odour matters.
If you want help picking the brand, this comparison of paint brands for Brisbane is a useful starting point.
When not to paint over
- Active leaks, rising damp or salt attack that is still visible after drying.
- Failing substrates such as crumbling plaster or rotten timber.
- Contaminants like silicone, heavy grease that will not shift, or chalk that keeps returning.
Fix the cause first. Painting over problems only hides them for a short time.
Need a second pair of eyes?
If you have one room that never cooperates, or a high traffic area that always scuffs, we can take a look and specify a system that lasts. For homes, this guide to planning a realistic paint timeline helps with sequencing. For commercial sites, a maintenance plan often costs less than a crisis repaint and ties in with why regular commercial painting saves money.
