During the winter months, partly due to the wet, cold climate, one of the most common problems to rear its head in our homes is the issue of mould.
Ventilating the rooms may prove useful, to avoid having air saturated with damp, but it may also worsen the situation, encouraging further rising of the water.
First and foremost, it is important to recognise that there are different types of mould, with different causes and solutions. Mould from condensation is what mainly forms on ceilings. It features black marks created due to the relation between hot, humid air in the environment and the cold wall surfaces. The causes may lie in faulty heat insulation due to thin exterior walls, excessive humidity levels in rooms, lack of ventilation or airtight windows that do not allow the damp air to flow out.
The first point involves an adaptation of our family habits. We should therefore avoid: - drying laundry in the home; - washing without ventilating the steam from the bathroom; - keeping bedroom doors closed at night; - keeping windows always closed (they should be opened at least 5 minutes, twice a day). In addition to this, chemical solutions are also available, such as sprays or water-repellent paints. If we take action immediately as the winter comes to a close, the wall can go back to its normal appearance, otherwise water-repellent paints will be required. One of the most natural methods used includes washing the wall with bleach or sodium hypochlorite.
For rising damp, i.e. that seen in the bottom corners, the above advice is of no consequence. Ventilating the rooms may prove useful, to avoid having air saturated with damp, but it may also worsen the situation, encouraging further rising of the water. In most cases, this type of mould derives from infiltrations from the ground or leaks of water associated with poor wall quality. In the first case, the solution is to repair the leak and then evaporate the water contained in the wall. The second is far more difficult to solve: complex mechanical and electro-osmotic works are required, and you are best seeking the advice of a surveyor/builder. Only afterwards, can water-repellent or evaporating paints be used.