Many believe high humidity is the cause of mould but it takes several factors for mould growth to appear. Temperature and Relative humidity are the two major factors but not independently. In the attached Psychrometric chart you will see the relationship between temperature,(bottom of chart) Relative humidity (the curved lines ranging form 10% to 80% RH . On the right hand side you will see g/kg. This related to grams of moisture in the air per kilogram of dry air.. You will see the same RG (say50% and thickest line,) can hold differing weights of moisture depending on the temperature
