Munich  - Mould caused by the insufficient airing of an apartment, energy-saving heating and windows and doors that are not properly sealed is a common problem in the autumn.

An initiative for energy conservation based in Darmstadt, Germany said the best way to avoid mould is to air the home frequently for 10 to 15 minutes. Sufficient heating throughout the home also helps prevent it, as does additional insulation of the exterior walls.

In a household of four, up to 15 litres of water enter the air as water vapour through breathing, sweating, cooking and drying clothes. This water vapour must be dispelled by airing the apartment. In the autumn the outside air is moist, therefore it's necessary to air the apartment more frequently than in the winter. Otherwise a moist film of water can condense on the outer walls, ceilings and corners of the home, creating places where mould can grow.

Mould that has built up on walls, wallpaper or tile can be fought off with little effort using isopropyl alcohol or other spirits. Mould on caulk or grout that has already been killed can be removed through steam cleaning. A chlorine cleaner can be used on serious mould, but it is important to also correct the cause of the mould.

Mould occurs less frequently in new apartments. When it does occur, it is usually because the apartment has not been sufficiently aired, said the initiative. In older apartments poor construction and insulation and leaks are usually the causes. Mould spores are invisible in the environment, but they start to grow in moisture. The ideal conditions for their growth are found in wallpaper paste, paper and other organic materials.

Mould causes an unpleasant smell, can damage plaster and lead to health problems. Mould spores can be either breathed in or enter the body through the skin. It is believed that some mould fungi induce respiratory illnesses and allergies.  (dpa)