Major cause of algae concerns using low-quality paint which is not algae-resistant or not water-resistant. The environment of area also causes the existence of algae, such as the surface which is rich in moisture or water, or situated near spot with high humidity including plumbing or wall with leakage. Area with low ventilation or exposure to sunlight, such as bathroom or ceiling board under the rooftop, is also prone to algae buildups. As well, coating old wall with algae without cleaning with proper fungicidal treatment is a cause of algae. Air-conditioning system is likely to cause algae as closed wall within air-conditioned room normally get cold and damp.
Characteristics of algae
Algae can be identified as black or brown spots which grow on paint film. Algae can exist on both exterior and interior walls, ceiling board and fence walls. Algae tend to grow with three conditions, which are appropriate humidity, appropriate food such as cellulose which is a composition of paint that suits well as algae’s food, and the existing buildup of algae.
In case the leakage exists, fix it first. Alternatively, if algae are found in air-conditioning system, remove algae in air-conditioning system first, such as cleaning the air-conditioner with sanitising agent. Improvements of the affected area, including enhancement of the ventilation and adding more sunlight, are recommended. For cleaning, sanitise the surface, prepare with primer and refinish.