Mould thrives in damp, humid environments. Common causes include condensation, poor ventilation, water leaks, and high humidity levels.

Mould often appears in bathrooms, kitchens, around windows, behind furniture, and in areas with poor airflow or water damage.

Some types of mould can trigger allergic reactions, respiratory issues, and other health problems, especially in people with asthma or weakened immune systems.

Probably not. You need to address the underlying moisture problem to prevent regrowth. This is why RBT have developed a powerful specific product to kill mould roots and spores.

Keep rooms well-ventilated, especially bathrooms and kitchens.

Use extractor fans or open windows when cooking or showering.

Dry clothes outdoors or use a vented dryer.

Fix leaks promptly and wipe away condensation regularly.

Use a dehumidifier in damp areas.

Yes, several types of mould can grow indoors. The most common include black mould (Stachybotrys chartarum), Aspergillus, Penicillium, Cladosporium, and Alternaria.

Black mould, also known as Stachybotrys chartarum, is a toxic type of mould that grows in damp, humid environments. It typically appears as dark green or black patches and can release allergens and irritants that may affect health, particularly in individuals with respiratory conditions. Exposure to black mould has also been linked to symptoms such as fatigue, difficulty concentrating, and mood changes, meaning it can potentially impact mental well-being as well.

Aspergillus can appear in various colours—green, yellow, or black—and often grows on walls, insulation, and food. Some species can cause allergic reactions or infections in people with weakened immune systems.

Penicillium is usually blue or green and spreads quickly. While some species are used in antibiotics, indoor growth can trigger allergies and asthma symptoms.

Cladosporium is a common mould that appears black or olive-green. It can grow on wood, carpets, and fabrics. It’s less toxic than black mould but can still cause respiratory irritation.

Alternaria is a dark mould that often grows in damp areas like showers and under sinks. It spreads quickly and can aggravate asthma and allergies.

Not all moulds are toxic, and some actually have beneficial uses. While many moulds can trigger allergic reactions, irritate the eyes, skin, or throat, and cause respiratory issues—especially with prolonged exposure—others are essential in medicine and food production. For example, certain moulds are used to make antibiotics like penicillin and foods such as cheese and soy sauce. Despite these benefits, mould growth in homes can negatively impact health, so it’s best to remove any visible mould promptly and fix the underlying moisture problem to prevent regrowth.

Mould comes in many colours, textures, and growth patterns, but identifying the exact type can be tricky without professional testing. While visual clues can help you spot mould, determining the species (like black mould or Alternaria) often requires lab testing. Regardless of type, any visible mould should be cleaned promptly, and the source of moisture should be addressed to prevent regrowth.