What is a fungicide?

A fungicide is a fungus-inhibiting, or anti-fungal, agent. In construction, fungicides are used to prevent mould, algae and moss growth on and within materials.

How it works

A fungicide kills fungi or inhibits their growth by interfering with their metabolism or cell structure. In construction, fungicides are added to or applied onto materials such as paint, timber, jointing compound, plaster and facade coatings. This keeps the surface clean for longer and slows down deterioration caused by biological growth. It is especially important in damp locations, for example in bathrooms, on north-facing facades that receive little sun and in cellars. Timber is treated with a fungicide by impregnating or preserving it, making it more resistant to wood rot and mould.

Application

Fungicides are used both preventively and curatively. Preventively, they are incorporated into building materials or coatings to stop growth; curatively, they are applied to an already affected surface after the mould or algae has first been removed. Because fungicides belong to the biocides, rules apply to their use and environmental impact. Sensible use always combines a fungicide with removing the underlying source of moisture.

Related terms

• Wood rot
• Impregnation
• Primer
• Mould

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