Not all mould is the same. Some varieties are relatively harmless, while others can damage your property or pose real risks to your health. Learning to recognise the different types of mould that appear indoors makes it easier to know when a quick clean-up is enough and when you need professional help.
The Three Classifications of Mould
Allergenic Moulds
Allergenic moulds are the most common and the least dangerous. They can trigger allergic reactions and asthma symptoms, particularly in children and people who are already sensitive, but they rarely cause serious illness in healthy individuals.
Pathogenic Moulds
Pathogenic moulds can cause infections, especially in people with weakened immune systems. While a healthy person may not be badly affected, those who are already unwell should avoid exposure entirely.
Toxigenic Moulds
Toxigenic moulds are the most hazardous because they produce toxic compounds called mycotoxins. Exposure has been linked to serious health effects, so these moulds should only ever be handled by trained professionals.
Common Types of Mould Found in the Home
Acremonium
A toxigenic mould that often develops in humidifiers, drain pans, and window sealants. It usually starts small and moist before drying into a fine, powdery growth.
Alternaria
The most common allergenic mould, typically found in damp areas like showers, sinks, and around leaks. It spreads quickly if moisture isn’t addressed.
Aspergillus
A very common indoor mould that can become toxigenic. It grows on walls, insulation, and stored food, and some strains produce harmful mycotoxins.
Aureobasidium
An allergenic mould often found on wooden surfaces, painted walls, and behind wallpaper. It appears pink or black and can irritate the skin and eyes.
Chaetomium
Commonly found in water-damaged buildings, this mould has a musty odour and can change colour as it matures. It thrives where there has been chronic moisture.
Cladosporium
An allergenic mould that grows in both warm and cool conditions, often on fabrics, carpets, and wood. It can trigger respiratory irritation.
Fusarium
Both allergenic and toxigenic, fusarium can grow even in colder temperatures and is often found in carpeting and fabrics after water damage.
Mucor
An allergenic mould that typically grows in thick patches near HVAC systems and areas with condensation. It can cause breathing difficulties.
Penicillium
A fast-spreading allergenic mould found on materials damaged by water, such as carpets, wallpaper, and insulation. It has a distinctive blue-green appearance.
Stachybotrys
Better known as “black mould,” this toxigenic variety is dark green or black and slimy. It grows on constantly damp materials and is associated with serious health effects.
Trichoderma
An allergenic mould that grows on wet surfaces and inside HVAC systems. Some strains also produce compounds that can break down building materials.
Ulocladium
Found in homes that have suffered significant water damage, ulocladium thrives in bathrooms, kitchens, and basements with high humidity.
Stop Mould Before It Grows
Identifying the type of mould in your home is an important first step, but removal should be handled carefully. If you suspect a toxigenic or widespread infestation, contact Mold Removal Winnipeg. Our certified technicians can test, identify, and safely remove mould from your property.
