Mould growth in a home is often more extensive than what is visible on the surface, which is why professional remediation involves more than simply cleaning a visible patch with household products. Small areas of surface mould, typically under about one square metre, can sometimes be addressed with proper cleaning and improved ventilation, but larger infestations usually require professional assessment to identify the underlying moisture source. Addressing the moisture problem itself is essential, since cleaning visible mould without fixing a leak or ventilation issue simply means the mould returns within weeks or months. Professional remediation typically involves containment to prevent spores spreading to unaffected areas during cleanup, along with specialised equipment for air filtration during the process. Health considerations matter too, particularly for households with respiratory conditions or young children, where even moderate mould exposure can worsen existing symptoms, making prompt action more important than in an otherwise healthy household. After remediation, a follow-up inspection confirming the underlying moisture issue has been resolved is worth insisting on, rather than assuming the problem is fully solved once visible mould is removed.