Why You Should Never Simply Paint Over Mould | How to Help Keep Mould From Coming Back

October 16, 2026

Don't Paint Over Mould: Why Surface Preparation Comes First

Seeing spotty patches of mould on walls or ceilings is a common frustration for many Australian homeowners. It often pops up in damp, poorly ventilated areas where steam and moisture like to linger, making bathroom mould and kitchen mould frequent household headaches. When it appears, your first instinct might be to grab a roller and cover it up with a fresh coat of paint. However, reaching straight for a tin of antimould paint without proper prep will only lead to bigger issues down the track.

Understanding how to remove mould correctly and preparing your walls is the most critical part of the job. If you want a lasting, fresh finish, you need to clean it, treat it, and use the right protective coatings to keep it away for good.

MOULD DESTROYING AND PREVENTATIVE SOLUTIONS

Why You Should Never Simply Paint Over Mould

It might be tempting to slap on a fresh layer of paint to hide unsightly marks, but painting over mould does not kill the underlying spores. Mould is a living fungus that thrives in humid environments. If you cover it up, the fungi will continue to feed on the surface underneath, eventually breaking through the new paint layer and causing it to bubble, peel, or discolour.

Proper mould removal is also essential for maintaining a clean living environment. As detailed in our guide on how to remove toxic mould and keep your family healthy, keeping indoor spaces free from active spore growth is vital for your home’s overall freshness and comfort. Covering up the issue only hides the trouble temporarily while allowing the underlying moisture and fungal growth to persist.

Step 1 – Remove and Treat the Mould

Before you open a single paint tin, you need to completely eliminate any active growth on the surface. Washing the area with regular soap or water isn't enough, as it leaves dormant spores behind that can easily reactivate.

Using a targeted mould killer is the best way to tackle the problem at the source. Applying a specialized formula, such as Mould Destroyer – Mould & Mildew Killer, helps break down the fungal growth on affected interior surfaces. Treating the area thoroughly ensures that the spores are neutralised before you move on to any cosmetic fixes or surface painting.

Step 2 – Prepare the Surface Before Painting

Once you have treated the growth, thorough surface preparation for painting is your next step. Paint requires a clean, stable, and completely dry foundation to adhere properly.

Clean away all residue: Scrub the treated area to remove all dead fungal traces, dirt, and soap scum. Use sugar soap for this.
Ensure the surface is dry: Never paint over damp walls. Allow the room to dry out completely using fans, dehumidifiers, or open windows.
Inspect for damage: Check if the previous paint is flaking or peeling. Scrape away any loose material so you are left with a smooth, solid surface. Patch and repair with a filler as needed.

Every major paint manufacturer emphasizes that all traces of mould must be entirely removed before applying new coatings. Skipping this prep work will compromise the performance of your new topcoat.

Step 3 – Add Mould Protection

Once your wall is clean, dry, and free of contaminants, you can focus on preventing future growth. If you have a favourite interior paint line that doesn't feature built-in resistance, you can upgrade standard finishes using a specialised anti mould paint additive.

Mixing an additive like Mould Defence directly into your chosen paint helps provide an extra line of defence against fungal growth. It is an easy way to boost the mould-resistant qualities of standard interior paints, helping to keep surfaces cleaner in areas prone to dampness.

Step 4 – Choose Paint Designed for Humid Areas

When painting high-moisture rooms, choosing the right topcoat makes all the difference. For spaces subject to constant steam and condensation, using a dedicated mould resistant paint provides the best long-term durability.

An excellent option for these demanding spaces is Haymes Ultra Premium Kitchen & Bathroom Interior Low Sheen. Formulated specifically for high-humidity wet areas, this paint offers several key benefits:

Provides integrated bacteria, mould, and mildew resistance.
Features exceptional washability for easy maintenance on interior walls and ceilings.
Requires a standard two-coat application for complete coverage.
Includes a 10-year mould and mildew protection guarantee (subject to the manufacturer's terms and conditions).

To benefit from product warranties like the Haymes 10-year guarantee, correct surface preparation is essential. The guarantee does not apply if all traces of mould have not been completely removed prior to application, or if the surface prep instructions weren't strictly followed.

How to Help Keep Mould From Coming Back

While using a high-quality mould treatment and protective coatings builds a strong barrier, long-term mould prevention relies on managing the environment inside your home. Mould needs moisture to survive, so controlling humidity is essential.

Improve ventilation: Always run exhaust fans during and after showers or cooking, and leave them on for 10–15 minutes after you finish.
Promote airflow: Open windows on clear days to let fresh air circulate through bedrooms and living areas.
Wipe down wet surfaces: Don't let water pool on bathroom walls, tiles, or kitchen splashbacks.
Control humidity: Consider using a dehumidifier in naturally damp rooms or during long periods of wet weather.

Keep Your Surfaces Mould-Free

Dealing with fungal growth on your walls requires a complete approach rather than a quick cover-up. By following a clear, step-by-step process—treat the growth, thoroughly clean and dry the surface, and apply a quality antimould paint or protective additive—you can enjoy a fresh, clean finish that lasts.

If you are planning your next painting project or need expert advice on selecting the right surface preparation products, the team at Crockers Paint is here to help. Drop into your local store or explore our full range of coatings and prep supplies online today.