Humidity in your house may appear due to the penetrations of rainwater, increased humidity coming from the soil, as well as from air rich in water vapor (4 people in the house produce approximately 10 liters of water per day, preparing or doing washing, breathing and sweating ).
Excess humidity can provoke the deterioration of walls, blisters in paintings, peeling wallpaper and the appearance of mold. It can help increase the consumption of woven. But mainly, it can provoke health problems (allergies and asthma).
Ventilation remains the simplest and most effective solution to eliminate humidity. Good ventilation also eliminates the smells and pollution accumulated in the house.
But widely open windows, while creating drafts, cannot be damaged and properly dried to dry the room. You should either create a ventilation system in the house, or think over the holes for ventilation in the main rooms, moisture sources (bathroom, toilets, kitchen), or equip the house with a system of control of mechanical distribution. This system is equipped with an electric motor that launches the fan. The air is set in motion and is constantly resumed in the house without losing heat.
It should still be known that in case of water penetration, even good ventilation will not be enough: it will be necessary to improve the tightness of the house.