Causes/and triggers for mould and moder

Humidity indoors has several reasons. It is created by damp masonry, rising humidity or increased room humidity. Especially in the cold season, warm air often settles in cold corners of the room in the form of condensation. Heat meets cold, creating condensate. Consider a bottle taken from the fridge. As soon as this happens, the bottle will be smashed in the same way!
Humans react to mold not only with visual discomfort, but often suffer health effects from the fungal spores, such as allergies, respiratory problems.

Where the moisture comes from


Old, historic buildings can have a damp masonry, especially due to rising humidity. New buildings still carry the building moisture in the masonry, especially in the first winter, because the “built-up” water could not yet evaporate. Subsequently built-in dense windows and doors no longer allow air exchange, condensation and soon mold!

Residential behaviour

Changing living behavior, such as frequent showers, tumble dryers, large leaf plants, insulated walls inside and outside, produces increased humidity. In order to avoid mould, it is necessary to ventilate more often when the humidity in the rooms is no longer adequate.

What can be done preventively against mould

Airing in case of humidity in rooms

The best orientation for ventilation is provided by a hygrometer. Especially in old buildings (until about 1980) during the winter (below +5 °C) when exceeding approx. 50 relative humidity must be ventilated. Rule of thumb: Cold air is dry air, warm air is rather humid air. It follows that airing is “more successful” in cold air, which can be early in the morning, in the evening, at night. This applies not only to living and working spaces, but above all to cellars.

Heat all rooms

Room temperatures should never fall permanently below 18 °c. Close doors to less heated rooms. Cold rooms are at risk for mold. Complete cooling and heating increases heating costs.

Absence during the day is not a problem

It is best to ventilate thoroughly before leaving the apartment. Close the windows and do not allow rooms to cool below 18 °c. Please do not leave the windows tilted – even risk of burglary.

Furniture away from exterior walls

5 to 10 cm distance from the wall allow air circulation; prevent the mould! Exterior walls are very cold, especially in old buildings. This is not a construction defect, but due to the age/material of the building. The worse the thermal insulation of the outer walls cooler and more humid living climate, the greater should be the distance of a piece of furniture from the wall. In extreme cases up to 20 cm, so that the air can circulate.

Examples of solutions for moisture and mould

Please note that you should have a moisture and dew point measurement performed by a competent professional. So that the situation can be assessed conclusively.

Here are a few suggestions for what they can do when mold is formed.

Mold on small areas

For a quick, short-term solution to small areas of mold, use our Mold Stop product. And remove and treat the mold.

In the longer term, it is also possible to treat the surface with MKL UltraLow paints. Remove the mold damp beforehand, then paint over with UltraLow paint without further pretreatment. We give you a 5-year warranty.

Heavy mould infestation in room corners and behind built-in, cabinets

For small areas of mold, you can use our Mold Stop product to remove and treat.

For larger mould surfaces
Application of a temperature control controlled by sensors in the interior as soon as partial areas are below the dew point. Application of Sump lime filler MARMOSANO Verde, – in all shades.

Alternative: AERO-dry sanier cleaning system, with standing air layer of approx. 1.8 cm

Damp, salinated masonry on the ground floor or higher, in the basement, in areas in contact with the ground, garages …

In the case of damp or salted masonry, a plaster exchange is usually necessary. The existing old plaster does not allow the masonry to breathe and thus dry. To ensure the drying of the masonry, we recommend our product MicroPore dehumidification plaster®. This allows the masonry to breathe and dry again. A long-term solution and you never have to worry about the masonry again.

If thermal bridges are the main problem, it should be fixed with the AERO-dry cleaning system.

In order to maintain the breathability of the masonry, the colours and spatula must also be breathable in the further processing steps.

For this purpose, we offer the appropriate color and/or lime coating in the system. Application of temperature control controlled by sensors in the interior and exterior as soon as partial areas are below the dew point. Application of Sump lime filler MARMOSANO Verde, – in all shades.