What Is Mould?
Mould is a common problem in Australian homes, particularly in bathrooms, showers and other areas where moisture tends to linger. But what exactly is mould, why does it keep appearing, and what does it mean when you find it around your tiles, grout or silicone?
Mould is a type of fungus. It occurs naturally in the environment and plays an important role outdoors by helping break down leaves, plants and other organic matter.
Mould reproduces by releasing tiny particles called spores. These spores travel through the air and are present almost everywhere, both indoors and outdoors. Usually, this isn’t a problem. However, when the spores settle on a surface with enough moisture and suitable material to feed on, mould can begin to grow.
In simple terms, mould needs three main things:
- Moisture
- A suitable temperature
- A source of organic material, such as dust, soap residue, body oils or other surface grime
Moisture is usually the most important factor. This is why controlling dampness is essential when trying to prevent mould growth.
Why is mould so common in bathrooms?
Bathrooms provide almost ideal conditions for mould. Showers and baths generate heat, steam and condensation, while wet surfaces may take a long time to dry – particularly in rooms with limited ventilation.
Mould is commonly found:
- Along silicone joints and seals
- On or around grout lines
- In shower corners and recesses
- Around windows and ceilings
- Behind fixtures or fittings
- In areas affected by leaks or failed waterproofing
Tiles themselves are generally easy to clean, but grout lines and ageing silicone can hold moisture and collect the residues that mould needs to grow. Once silicone becomes deeply stained, damaged or begins separating from the surrounding surface, ordinary cleaning may no longer restore its appearance.
Is all black discolouration mould?
Not necessarily. Dark marks around grout and silicone may be caused by mould, but they can also result from dirt, soap residue, mineral deposits, degraded silicone or staining that has penetrated the surface.
Mould can appear black, green, grey, brown or even white. It may look like spots, patches or a powdery or fuzzy growth and can sometimes produce a musty smell.
If discolouration repeatedly returns after cleaning, there may be an underlying moisture problem that needs attention.
Can mould affect your health?
Some people can be more sensitive to mould spores than others. Possible reactions include a blocked or runny nose, irritated eyes or skin, coughing and wheezing. Mould exposure may also trigger symptoms in people with asthma or allergies.
Large or persistent areas of mould should be approached carefully, particularly where water damage, flooding or hidden moisture may be involved.
Why does mould keep coming back?
Removing visible mould does not necessarily remove the conditions that allowed it to grow.
Recurring mould may indicate:
- Poor ventilation
- Regular condensation
- Surfaces remaining wet for long periods
- Leaking plumbing
- Failed or deteriorating silicone
- Cracked, damaged or missing grout
- Water entering behind tiled surfaces
- An unresolved waterproofing or building issue
The key to controlling mould is controlling moisture. Cleaning the surface may improve its appearance, but unless the moisture source is addressed, the mould is likely to return.
What can you do about mould around tiles and grout?
Good ventilation, regular cleaning and allowing wet areas to dry fully can help reduce mould growth. Exhaust fans should be used while showering and, where practical, left running afterwards. Shower screens, tiles and silicone can also be dried with a squeegee or cloth.
Where grout or silicone has deteriorated, professional attention may be needed. Replacing failed silicone, repairing damaged grout and thoroughly cleaning tiled surfaces can help remove affected material and make the area easier to maintain.
However, if the mould is widespread, located behind walls or tiles, or connected to a significant leak or building defect, a specialist mould remediator, plumber or building professional may be required.
A healthier, fresher-looking tiled area
Mould is more than an unsightly mark. It is often a sign that moisture is remaining in an area for too long. Understanding why it forms is the first step towards managing the problem properly.
If mould and staining around your grout or silicone are making your bathroom look tired, your local Tile Rescue specialist can assess the tiled area and recommend suitable rejuvenation options.
