How do you paint rendered exterior walls?
By J. James Painting Contractors. Updated . 8 min read.
Short answer
You paint rendered exterior walls once the render has cured and the surface is clean and sound. Dulux and Taubmans both say new cement render needs at least 28 days before paint. Old render needs a wash, a tape test on the old paint, any white salt cleaned off and holes filled. Then it gets an exterior topcoat. Dulux's Render Refresh, for one, goes on in two coats over painted render and three over bare.
On the Sunshine Coast, our instant estimate puts a basic rendered home at $7,000 to $14,000 including GST for a standard repaint. That's a guide range, not a quote. We've painted up here since 1985, and the firm price comes after a free site visit.
Yes, you can paint straight onto render, once it's sound and clean
Yes, as long as what's underneath is firm. The makers' prep steps deal with salt, chalky old paint and a flaking coat underneath. Fresh render also needs time to cure first.
Both big makers cover render in their own instructions. Dulux's Weathershield Low Sheen page has a prep section for bare masonry, and Taubmans lists rendered masonry among the surfaces for its All Weather paint, which it calls self-priming. So a primer isn't always a must. It depends on the product and the wall.
One catch worth knowing. Dulux's Weathershield guarantee terms say it doesn't apply to substrate failure, so if the render under the paint is breaking down, new paint won't save it. Our exterior house painters walk the house first.
New render: wait at least 28 days, longer if you can
Fresh render should cure for at least four weeks before paint goes on. Dulux's 1Step Prep page says freshly laid masonry and cement-based surfaces should cure for a minimum of 28 days. Its Weathershield Low Sheen page says the same for unpainted masonry. Taubmans also says at least 28 days for new render.
Some advice runs longer. Dulux's Render Refresh instructions say four to eight weeks, depending on how thick the render is and how it dries. Dulux's trade advice says at least 30 days and ideally a full year.
The wait is about lime. Dulux explains that fresh masonry is likely to hold lime, which is very alkaline. Until that lime reacts with carbon dioxide in the air, it can attack the paint film. The result is colour loss and paint that breaks down early.
If the builder can't wait that long, Dulux's fix is an alkali-resistant sealer or water-based primer first, then a top quality 100% acrylic exterior paint.
Prep for old render: wash, test, clean, fill, prime
Old render needs more prep than new. Here's the order, drawn from the Dulux and Taubmans product instructions.
- Wash it down. Dulux says to wash masonry with water and a stiff brush to shift loose material.
- Tape test the old paint. Cut an X with a sharp knife, press 10cm of tape firmly over it and rip it off fast. If paint comes away, the loose paint has to come off before you repaint. Try it in a few spots around the house.
- Deal with chalk. On a chalky surface, Dulux says to sand back to a firm surface and dust off.
- Clean off white salt. Taubmans says a wire brush or pressure wash. Dulux suggests a wipe with a 5% acetic acid solution (white vinegar) or its Concrete and Paving Etch & Clean.
- Fill holes. Dulux's Render Refresh instructions say to fill holes in masonry with grouting cement.
- Prime bare or patched spots. Dulux 1Step Prep is a water-based primer, sealer and undercoat. Outside, Dulux says the topcoat should go on within a week of it.
- Pick your day. Dulux says it has to stay above 5°C while the paint goes on and dries, and rain or overnight dew on wet paint can damage it.
On our own jobs the order is wash, scrape, sand, fill, seal, undercoat, then topcoat. Sanding, filling and sealing take most of the days on an exterior.
A two-storey wall can need scaffold, and that part is a job for a painter. If your render goes up that high, stop the DIY at ground level.
Which paint and how many coats: an exterior acrylic, two coats or more
For fresh masonry that can't cure long enough, Dulux's trade advice is an alkali-resistant sealer or water-based primer, then a top quality 100% acrylic exterior paint, because the acrylic binder resists alkali. Coats depend on the product and the wall: Render Refresh, for one, goes on in two coats over painted render and three over bare. Here's what each maker says, straight from their own pages.
| Product | What the maker says it's for | Coats and key notes |
|---|---|---|
| Dulux Weathershield Low Sheen | Exterior topcoat, with prep steps for bare masonry | Bare masonry cured 28 days first. On very porous walls, thin the first coat with up to 100mL of water per litre |
| Dulux Weathershield Render Refresh | Previously painted brick, concrete, fibre cement and masonry. High build, helps fill and bridge fine cracks | Two generous coats on painted walls, three on unpainted |
| Taubmans All Weather | Self-priming exterior paint. Listed surfaces include rendered masonry | Touch dry in 30 minutes, recoat in 2 hours |
| Dulux 1Step Prep (water based) | Primer, sealer and undercoat for interior and exterior walls | One coat. Outside, topcoat within a week |
| Taubmans Armawall Primer | Acrylic primer and sealer for cement render, with efflorescence and alkali resistance | Preps the surface for the Armawall Texture System |
Dulux Weathershield and Taubmans All Weather do most of the work on our exteriors. We're a Dulux Accredited Painter and Taubmans Endorsed. Coast-facing and canal-front walls usually get a sealer pass first.
Dark colours can need extra coats, which we price at the site visit. For help picking a shade, see choosing exterior house colours.
Cracks, chalking and white salt marks: fix the cause before you paint
Each of these faults has its own fix, and each one gets fixed before new paint goes on.
Fine hairline cracks. These are the easy ones. Dulux says Render Refresh is high build and helps fill and bridge fine cracks, so it suits a wall with plenty of them.
Wide cracks, stepped cracks or cracks that keep growing are a job for a builder or engineer to look at before anyone paints. Dulux pitches Render Refresh at fine cracks, not big ones.
Chalking. Paint won't grip a chalky surface. Sand back to a firm surface first, as Dulux says.
White salt marks. That's efflorescence. Taubmans describes it as white, powdery deposits on render, caused by moisture moving through the wall and carrying salts to the surface. It says this is a frequent issue in coastal homes. Dulux's Render Refresh instructions say it must be treated before painting.
Colour loss or breakdown on new render. Dulux calls this poor alkali resistance. Dulux says it happens when solvent-based paint goes on new masonry that hasn't cured, while the lime in it is still very alkaline. For peeling on older paint, read why exterior paint peels.
Once it's painted, keep it clean. Dulux recommends washing Weathershield every 6 months in coastal areas and every year in sheltered or inland areas. Our guide to how long exterior paint lasts covers the rest of the upkeep.
What painting a rendered house costs on the Sunshine Coast
A standard repaint of a basic single-storey rendered home starts at $7,000 to $14,000 in our instant estimate. Condition and storeys move it from there. These are guide ranges for the standard tier, including GST and rounded to the nearest $100.
| Job | Guide range (inc GST) |
|---|---|
| Single storey, render in good condition | $7,000 to $14,000 |
| Single storey, render in poor condition | $8,800 to $19,600 |
| Double storey, render in good condition | $8,400 to $19,600 |
Most full exteriors run five to ten working days depending on access. For how render stacks up against weatherboard, see exterior house painting cost. We work right across the Sunshine Coast, and we're QBCC licensed (licence 1281728). We quote after a free site visit, so the number you get is the real one.
Common questions
Questions people ask
Can you paint directly onto rendered walls?
Yes, as long as the render is cured, clean and solid. Some exterior paints, like Taubmans All Weather, are self-priming and list rendered masonry as a surface they suit. Bare patches, chalky spots or fresh render may still need a primer or sealer first. If old paint lifts off in a tape test, strip the loose stuff before you paint over it.
How long should new render cure before painting?
At least 28 days, going by both Dulux and Taubmans. Dulux's Render Refresh instructions stretch that to four to eight weeks depending on thickness and drying, and its trade advice says a full year is ideal. If you can't wait, Dulux says to use an alkali-resistant sealer or water-based primer, then a top quality 100% acrylic exterior paint.
What do you put on render before painting?
Clean water and a stiff brush first, to shift dust and loose grit. Salt deposits come off with a wire brush or a weak white vinegar wipe. Then a primer or sealer where the wall needs one. Dulux 1Step Prep and Taubmans Armawall Primer are two water-based options, and Taubmans lists cement render among the surfaces Armawall suits, and says it has efflorescence and alkali resistance.
What is a good paint for exterior rendered walls in Australia?
For fresh render that hasn't had time to cure, Dulux's trade advice is an alkali-resistant sealer or water-based primer, then a top quality 100% acrylic exterior paint, because the acrylic binder resists alkali attack. We mostly use Dulux Weathershield and Taubmans All Weather. Dulux also makes Weathershield Render Refresh, a high build coat that helps fill and bridge fine cracks in previously painted render. Which one suits your house depends on the wall's condition and how much salt and sun it cops.
Can you use Dulux Weathershield on render?
Yes. Dulux recommends the Weathershield range for exterior surfaces, and the Weathershield Low Sheen instructions include prep steps for bare masonry, with 28 days of curing first. For render that's already painted and has fine cracks, Dulux makes Weathershield Render Refresh, which goes on in two generous coats over painted walls.
How do I paint an old rendered wall on a two-storey house?
The prep's the same as any old render: wash, tape test, clean off salt, fill, prime. The difference is height. Upper walls can need scaffold, so that part is a job for a painter. In our estimate a double-storey rendered home starts at $8,400 to $19,600 for a standard repaint, with the firm price after a free site visit.
Do you paint rendered homes across the Sunshine Coast?
Yes. We've been painting Sunshine Coast homes since 1985, render included, and our crew works from Caloundra to Noosa. Coast-facing and canal-front walls usually get a sealer pass before the topcoat. Check our locations page for the suburbs we cover, then grab a guide price from our instant estimate.
Where to next
Keep reading
Sources
- 1Step Prep Water Based Primer, Sealer & Undercoat, Dulux. Accessed 4 October 2026.
- Weathershield Low Sheen, Dulux. Accessed 4 October 2026.
- Weathershield Render Refresh, Dulux. Accessed 4 October 2026.
- How to Fix Poor Alkali Resistance Problems, Dulux. Accessed 4 October 2026.
- Preventing Substrate Failures: Bleeding, Efflorescence and Mould, Taubmans. Accessed 4 October 2026.
- Taubmans All Weather Exterior Paint, Taubmans. Accessed 4 October 2026.
- Armawall Primer, Taubmans. Accessed 4 October 2026.