How mould grows in the home

Favourable environment

To grow, mould needs a favourable environment, which is characterised by:

• a high level of moisture;
• an appropriate temperature;
• a source of food.

Any organic matter, such as wood, cardboard, wallpaper, synthetic materials, dust, etc., can serve as food for mould. Eliminating the moisture or the source of food will prevent the growth of mould.

Mould also spreads in non-visible places, such as under floor coverings, behind skirting boards or wallpaper, etc.

Construction defects

Construction defects often result in the growth of mould. Damage and defects that can cause mould growth include the presence of thermal bridges (ineffectiveness of the thermal protection envelope of the materials used to insulate a building), a lack of watertightness, a burst pipe or other damage that causes water to run or seep in (water comes up through the foundations). Remember that, depending on the materials used, new constructions can contain excess moisture, which will only disappear over time.