Under the right conditions, both mould and mildew can grow in our homes. They’re commonly found in bathrooms and high-humidity areas and must be cleaned away, both for aesthetic and health reasons.
However, knowing which you’re dealing with is crucial to effectively deal with the problem.
This guide looks at the four key differences between mildew vs. mould. By the end, you’ll know how to identify mould and mildew, the health risks of each, and the best cleaning practices.
Are Mould and Mildew the Same?
The words “mould” and “mildew” are often used interchangeably, leaving many people believing they’re the same thing.
Mould and mildew certainly have many similarities. Both are types of fungi commonly found in indoor and outdoor environments, often thriving in damp and humid environments like bathrooms.
However, while they share similarities, they are distinct types of fungi.
Mildew is the less invasive and troublesome of the two, often described as an “early-stage mould,” whereas mould is known for its severe adverse health effects.
In the section below, we look closer at the differences between mould and mildew and help you identify which you’re dealing with.
What’s the Difference Between Mildew and Mould?
There are four key differences between mildew and mould:
Colour and texture
Location of growth
Associated health risks
Cleaning methods
1. Appearance
One of the easiest ways to tell the difference between mould and mildew is to look at their appearance.
Mildew is typically a powdery or fluffy growth with a flat pattern on the surface, often resembling a stain. It is usually light grey or white in colour but can darken during the later stages.
On the other hand, mould tends to appear as fuzzy or slimy patches with irregular patterns and a textured surface.
It can exhibit various colours, such as black, green, white, or brown. Some moulds are so dark that they’re often mistaken for dirt and overlooked.
2. Location
Both mould and mildew thrive in poorly ventilated areas that have lots of moisture. They rely on a damp, high-humidity environment.
Lack of sunlight and dirt can also encourage both mould and mildew to grow. However, they tend to develop in different places around the home.
Mould requires higher humidity levels and tends to grow on organic materials like wood, paper, and fabric.
It commonly emerges in areas with water leaks, flooding, or inadequate ventilation, making basements, attics, and crawlspaces susceptible.
Mould can also develop on walls, furniture, ceilings, and around leaky pipes, as well as on materials like damp carpets, insulation, and wooden surfaces.
On the other hand, mildew commonly appears on bathroom tiles, shower curtains, and damp clothing.
Additionally, mildew can be found on indoor plants and their soil, as well as on paper materials like books or documents exposed to humidity.
3. Health risks
Both mould and mildew can have negative health consequences. However, mould is the more harmful of the two.
Exposure to mould spores can lead to allergic reactions, respiratory issues, and worsened asthma symptoms.
If you have mould in your home, you might suffer from sneezing, coughing, and wheezing.
Additionally, some moulds produce mycotoxins as byproducts as they grow. These mycotoxins can be harmful if ingested or inhaled, potentially causing severe health problems over extended exposure.
More than 200 mycotoxins have been identified, and research into the health consequences is ongoing. However, exposure should be avoided wherever possible.
Health effects from mildew exposure are generally milder compared to mould exposure.
However, while less harmful than mould, mildew can still trigger allergies and respiratory irritation, particularly in individuals sensitive to such irritants.
4. Cleaning methods
To get rid of mould or mildew from home surfaces, you’ll need to use potent cleaning agents such as bleach (be careful not to mix it with anything else), white vinegar, mould wash concentrate, or commercial mould removers.
Because of the health risks, you must wear protective gear (gloves, masks, goggles, etc.) when cleaning.
These products can be used to eliminate both types of fungi. However, mildew is typically easier to clean than mould.
This is because mildew grows on the surface of a material, whereas mould growth can occur within porous materials.
Take a bathroom tile as an example. Mildew will cover the surface of the tile, whereas mould can penetrate into the tile itself.
Hannah has a passion for cleaning. She worked her way around Australia by cleaning hostels in exchange for free accommodation and used her cleaning skills to bag a job as a chalet host for a luxury ski company in France.
