Mould Removal Products That Actually Work (and Those That Don’t)
Walk down the cleaning aisle of any Melbourne supermarket and you will find a dozen products screaming “KILLS MOULD!” in bold letters. Online, the advice is even more overwhelming: bleach, vinegar, tea tree oil, hydrogen peroxide, baking soda, clove oil. Everyone has a favourite. The problem is that many of these products either do not work the way people think, work only on certain surfaces, or create a false sense of security while mould continues growing beneath the surface.
Here is an honest breakdown of what actually works, what does not, and when you need to stop reaching for products and start reaching for the phone.
Products That Work (With Limitations)
Hydrogen Peroxide (3%)
Hydrogen peroxide is one of the more effective household products for surface mould. It has antifungal and antibacterial properties, works on a range of surfaces, and does not produce toxic fumes. Apply it undiluted to the mouldy surface, leave it for 10 to 15 minutes, and scrub with a brush before wiping clean.
Limitation: It is a surface treatment only. It cannot penetrate porous materials to reach mould roots embedded in plasterboard, grout, or timber.
Commercial Mould Removers (Chlorine-Based)
Products containing sodium hypochlorite (the active ingredient in bleach) in a gel or spray formulation designed for mould removal can be effective on hard, non-porous surfaces like tiles, glass, and sealed benchtops. The gel formulations, in particular, cling to vertical surfaces like bathroom walls and shower screens longer than liquid sprays.
Limitation: Chlorine-based products do not kill mould on porous surfaces. On plasterboard, timber, and grout, they may bleach the visible discolouration without killing the underlying fungal network.
Concrobium Mould Control
This non-toxic, commercially available product works by creating a physical barrier that crushes mould spores as it dries. It can be used on a wider range of surfaces than bleach-based products, including porous materials, and it leaves a residual protective layer.
Limitation: It is more effective as a preventative treatment and for light contamination. Heavy mould growth on compromised building materials still requires physical removal.
Products That Do Not Work (or Not How You Think)
Household Bleach (Neat or Diluted)
This is perhaps the most widely recommended and most misunderstood mould treatment. Bleach is effective at removing mould staining on non-porous surfaces, but its ability to kill mould on porous materials is limited. The chlorine component sits on the surface while the water component soaks in, potentially adding moisture that encourages regrowth. Many people bleach their walls, see the mould disappear, and believe the problem is solved, only to watch it return weeks later.
White Vinegar
Studies have shown vinegar can kill some mould species, but its effectiveness varies significantly depending on the mould type and the surface. It is not a reliable broad-spectrum treatment. It also does nothing to address mould embedded in porous materials. The widespread belief that vinegar “kills 82% of mould species” traces to a single informal study that has never been replicated under controlled conditions.
Essential Oils (Tea Tree, Clove)
Tea tree oil and clove oil have demonstrated antifungal properties in laboratory settings. However, the concentrations required for effective mould killing are impractical for household use, and their effectiveness on real-world building surfaces (as opposed to petri dishes) is unproven. They may help as a mild deterrent on cleaned surfaces but should not be relied upon as a primary mould removal solution.
Baking Soda
Baking soda is a mild abrasive that can help scrub surface mould and may slightly raise surface pH, making conditions less favourable for mould. But it does not kill mould and is essentially a cleaning aid rather than a mould treatment.
When Products Are Not Enough
The fundamental limitation of every product on this list is the same: they treat the surface. Mould that has penetrated porous building materials, established within wall cavities, or colonised structural elements cannot be resolved with any spray, wipe, or application. These situations require physical removal of contaminated materials by qualified professionals following proper remediation protocols.
Consider getting a professional mould removal quote if any of these apply:
- The mould covers an area larger than one square metre
- Mould keeps returning after cleaning, which is covered in detail in our guide on preventing bathroom mould
- The affected material is porous (plasterboard, timber, carpet)
- You can smell mould but cannot find the source
- Household members are experiencing health symptoms
We connect Melbourne homeowners with qualified mould removal specialists who use professional-grade equipment and techniques that go far beyond anything available in a spray bottle. For small surface mould on hard surfaces, the right product can help. For everything else, professional remediation is the only reliable solution.
Take Action Today
If you have been battling mould with supermarket products and it keeps coming back, the problem is deeper than the surface. Use our free assessment tool to evaluate your situation and find out whether you need professional help.