Algal and Fungal Resistance of Silicate Mineral Paints

One of the biggest problems that is routinely faced in façade maintenance is biological fouling that is either algal or fungal in nature. Fungal infestations (diffuse black patches) are less common outdoors as fungus growth is hampered in well-lit areas. Algae (Fluorescent to Dark Green patches) however thrives on sunlight and wet conditions and requires very little food for growth as it derives most of its mass from carbon dioxide in the atmosphere through photosynthesis.

The most common approach is to incorporate algaecides and fungicides in the paint film itself that works by leaching out and actively killing the algae or fungal infestation from establishing itself or propagating. The problem is that the leaching process depletes them over a period of time making it a temporary solution. Further, these chemicals are toxic and pollute the environment around us.

The root cause of algae is moisture in the form of dampness or constant wetness resulting form continuous rainfall (See our article on “The Unusual Intensity of the Indian Monsoon”).

Another factor in biological fouling on walls is excess dirt pick up. Dirt does not always mean only soil particles but algal and fungal spores as well. Further, organic matter lodged with dirt contributes to food for these micro-organisms. There is a strong correlation between dirt pick up and biological fouling. Acrylic paints typically tend to pick up dust due to their tackiness and organic nature (See our article on “Dust Resistance of Silicate Mineral Paints”)

Zydex Silicate Mineral Paints are highly resistant to algae and fungal attacks due to their naturally high alkalinity (See our article on “What is Potassium Silicate”) which hinders their growth. Further their breathability ensures that structures dry out quickly depriving them of moisture and hence further hindering their growth (See our article on “What Is Paint Breathability and Why is it Important?”). A lack of organic content combined with their superior dirt pick up properties further deprives microorganisms of carbon sources hindering them further. Ultimately this results in facades painted with Zydex Silicate Mineral Paints remain clean and fresh looking for decades!