Bathrooms are notorious for mould growth due to high humidity and condensation resting on walls and ceilings. Hot showers and baths create lots of moisture giving mould a foothold in your home.
Paint alone is not enough, ensuring adequate ventilation to reduce humidity is essential. The best anti mould paint for bathrooms is one that will work to help regulate the moisture rather than creating a plastic filled barrier.
Conventional wall paints rely on synthetic biocides sealed into a plastic paint film. In bathrooms, this can trap moisture behind the surface and lead to mould returning once the chemicals lose effectiveness.
We’re passionate about natural paints, and in this article we’ll explain why our anti mould paints will out perform plastic and chemical laden conventional paints by working in harmony with your home.
Why Bathrooms Are Prone to Mould
Bathrooms combine high moisture levels with short, intense humidity spikes. If there’s inadequate ventilation after a shower, the moisture will linger in the air - creating the conditions for mould spores to thrive.
Every shower releases warm water vapour into the air. When that moisture meets colder surfaces such as external walls, ceilings, window reveals, or the edge where tiles meet painted plaster, it condenses.
Where mould typically grows in bathrooms:-
- Ceiling corners and above the shower or bath.
- Around window frames and reveals.
- Along the top edge of tiled areas.
- Cold external wall sections behind towel rails or shelving.
Paint is only part of the solution to bathroom mould. Making sure you have an extractor fan installed or opening a window during and after showering is a key part of keeping your bathroom pristine and mould free.
Best Anti Mould Paint for Bathrooms
The best anti mould paint for bathrooms is a highly breathable mineral paint, such as a silicate based or lime based paint, which allows moisture vapour to escape and creates a naturally mould resistant surface without relying on short term synthetic fungicides.
Bathrooms place far greater demands on paint than other rooms in the home. Daily steam, rapid temperature changes and frequent cleaning mean that paint must cope with high humidity while still allowing walls and ceilings to dry effectively. When moisture is trapped behind a paint film, mould is far more likely to return.
Our hero anti mould paints are:-
AURO High Grade Silicate Paint No. 303
Auro 303 is the premium option for bathrooms where mould repeatedly returns and you need a durable, breathable finish that can cope with condensation and regular wipe down.
Key properties:
- Highly breathable with an SD value < 0.01, allowing moisture vapour to escape quickly after bathing or showering.
- Natural mould resistance from alkaline silicate chemistry rather than added synthetic fungicides.
- VOC < 1 g/l, preservative free, low emission and low odour, making it suitable for enclosed bathroom spaces.
- Matt finish with strong opacity and wet scrub resistance Class 2, which is particularly practical in bathrooms where surfaces need to be cleaned more often.
Auro 303 is our premium anti mould paint and one of our bestselling products, especially for bathrooms with poor ventilation or persistent condensation issues.
AURO Anti Mould Paint No. 327
Auro 327 is a traditional lime based anti mould paint with excellent vapour permeability, designed for mineral surfaces where breathability is the priority.
Key properties:
- SD value < 0.05 m, providing high vapour permeability for moisture-prone walls and ceilings.
- Pure lime formulation with high natural alkalinity, creating a surface environment that naturally inhibits mould growth.
- Trace VOC content. The Technical Data Sheet for Auro 327 lists VOC at 0 g/l. Due to UK regulatory requirements we avoid terms like VOC free, but this is about as clean as paint can be.
- Matt finish with a classic lime character, well suited to traditional bathrooms and older buildings.
This paint is ideal for mineral walls, lime plaster and solid masonry where moisture needs to move freely through the wall, but where heavy scrubbing is not required.
Which should you choose?
- Choose AURO 303 if you want the best overall performance for most bathrooms, particularly where durability, wipeability and resistance to recurring mould are important.
- Choose AURO 327 if your bathroom has lime or mineral substrates, you want a traditional finish, and maximum breathability is the priority. Note: Auro 327 has a lightly textured finish due to inclusion of natural lime in the formulation.
Why Natural Anti Mould Paint Works Better in Bathrooms
Natural anti mould paint can be more effective than synthetic chemical based alternatives and offers superior long term performance in high humidity environments like bathrooms.
Our natural mould resistant paints use breathable mineral based formulas. Here’s why that matters in bathrooms:
- Breathability - Breathable paints allow moisture vapour to pass through the paint layer rather than sealing it into the wall. In bathrooms, this helps walls and ceilings dry more quickly after showers and baths, reducing the damp conditions mould needs to thrive.
- Naturally high pH - Silicate and lime paint systems are naturally alkaline. This creates a surface environment that inhibits mould growth through natural fungicidal and algicidal properties.
- Low VOC content - Our anti mould paints contain trace VOC levels, helping to protect indoor air quality in bathrooms where ventilation may be limited.
- Long lasting mould resistance - Because this approach relies on breathability and alkalinity rather than synthetic biocides, it does not depend on synthetic chemical additives that degrade over time. This makes it a more durable and reliable solution for bathrooms where conventional anti mould paints often fail.
Before Repainting a Mouldy Bathroom
Even the best anti mould paint will fail if it is applied over active mould or a damp surface. Before you grab a paint brush, you need to tackle the underlying causes of mould and eliminate any active spores.
Any visible mould must be fully removed before repainting. We recommend a simple two-step approach using our own natural anti mould cleaning system:-
- AURO 412 Mould Remover to clean and remove existing mould and surface spores.
- AURO 413 Mould Stop to inhibit regrowth before repainting.
Once treated, allow the surface to dry properly. Painting over residual moisture traps damp behind the coating and undermines even the most breathable paint.
Natural Solutions for Mould Elimination
Bathroom mould is not solved by stronger chemicals or by sealing walls. It is solved by moisture management.
When correct preparation is combined with a genuinely breathable, naturally mould resistant paint, the conditions mould needs to survive are significantly reduced. That’s why mineral systems perform so well in bathrooms.
Need advice? Contact us and one of our paint experts will be happy to help!
