How to Beat Mould: A Practical Guide

Winter in Uruguay often brings not only cool weather but also an uninvited guest: mould on the walls. High humidity combined with cold concrete structures creates an ideal environment for fungus. If you notice black spots, there is no need to panic. This problem can be solved if you approach it as an engineering task.

Why Mould Appears

The main cause in Uruguay is condensation. When humid air touches a cold wall, it turns into water. Mould does not choose dirty homes; it chooses homes with no air movement and walls that become very cold.

Step 1: Remove the Surface Growth

First, remove the visible fungus.

• Bleach (Lavandina): the quickest method. Mix bleach with water at a one-to-three ratio and wipe the affected areas. This kills fungus on the surface but does not protect against its return.
• Professional products (Antihongo): at any hardware shop, ask for products marked Antihongo. Brands such as Sika or Brikkol offer compounds that penetrate the wall structure. They are more effective than household products because they address the cause, not only the result.

Step 2: Provide Ventilation

Chemicals will not help if moisture keeps accumulating.

• Air the home: even on cold days, open the windows for 15 minutes a day. A through-draft is needed to drive out stagnant humid air.
• Do not dry laundry indoors: in Uruguayan conditions, this is the quickest route to fungus in the corners. If there is no alternative, be sure to keep a window in that room slightly open.

Step 3: A Technical Solution

If mould returns, natural ventilation is not enough.

• Dehumidifier (Deshumidificador): this is the most effective tool in Uruguay. The appliance collects excess moisture from the air in a container. Many residents note that once they have a dehumidifier, the need to repaint the walls constantly simply disappears.
• Hygrometer: buy a simple humidity sensor. The normal range for a home is 45–60 percent. If the device reads higher, it is time to act.

Step 4: Prevention

Once it has been cleaned, the wall needs protection.

• Anti-fungal paint: use paint that already contains antiseptic additives. This is the standard for Uruguayan renovations.
• Insulation: if fungus appears only in one corner, there is a thermal bridge there. In such cases chemicals are only a temporary measure. Installing a thermal-insulation panel or insulating the wall externally is the solution.

Fighting mould requires a systematic approach. First remove the consequences, then change the microclimate in the apartment. If you face this problem, start by buying a hygrometer and visiting a hardware shop for a product marked Antihongo. That will give you control of the situation and help you spend the winter in a dry, healthy home.