Condensation, infiltration, leaks… Several reasons can be at the origin of the humidity which attacks your house. Sometimes they even combine… -The leaks It is probably the best known cause, but it is not the most widespread. It invites itself into your home through the roof and attacks the walls before generally attacking the walls. Originally, very often the roof is weakened and lets in rainwater as well as that resulting from the condensation of dew. Have your home's roofing professionally inspected. Once the faulty tiles are repaired, a waterproof paint specially provided for this purpose should effectively protect you. -Hair lift Water infiltrates through the ground and rises in the walls. It mainly affects old houses that are not equipped with anti-humidity systems. By installing a hydrophobic barrier less than a meter from the ground, water should no longer come into your home. -L'infiltration Coming from the facade or more generally from the roof, rainwater and dew condensation take advantage of the failures of your exterior insulation to trickle down the walls and then into your interior. -The condensation It can be of two types: - interior condensation: every time we cook food with steam, that we take a shower and even when we breathe, we give off water vapor. In closed rooms, this water vapor does not escape, it stagnates and ends up depositing on walls and windows. In most cases, it is enough to ventilate regularly by opening the windows to stop it. -external condensation: The temperature difference between the exterior and the interior creates a thermal shock. Condensation is the result of the meeting between its two masses of different temperatures. In winter, its presence on the tiles is easily explained by the large temperature difference between the exterior and the interior. It is more in Summer that the condensation must alert you. Note that warm air supports more moisture than cold air. If you cannot distinguish the origin of the humidity in your interior, the observation of possible molds could help you: -the presence of saltpetre, a whitish foam indicates in most cases a problem of capillary rise or d 'infiltration. -The mold that appears in the corners of rooms and on damp objects (toilets, taps, sinks, etc.) is often due to a condensation problem. - As for the orange mosses and mushrooms, they are the testimony of a water leak.