Effectively prevent mould in winter

Root cause analysis and prevention with functional colours

Mould growth in living and working spaces occurs mainly in the autumn and winter months. Even with regular heating, traces of moisture or mould stains can appear on walls, ceilings and corners of rooms. The causes are mainly to be found in the physical relationships between surface temperatures, room humidity and thermal bridges. A sound understanding of these factors is crucial in order to prevent mould effectively and sustainably – also with the help of wall paint.

Physical causes of mould formation

One of the main causes of mould growth are thermal bridges that occur during the construction phase. Uninsulated corners, connections to windows or roofs and cracks in the construction lead to lower surface temperatures locally. At these points, the temperature can fall below the dew point of the room air, causing moisture to condense – creating ideal conditions for mould.

Other causes are:

• cracks in the façade or defective roofs
• lack of protection from rain
• rising damp in masonry
• insufficient drying out after construction work
• insufficient air circulation due to tightly closed windows and doors
• improper heating and ventilation

Older, dirty or chalky paintwork, highly absorbent textured plaster and organic deposits also encourage the initial colonization of mould spores. In such cases, a mold-inhibiting paint can help to reduce the formation of new mould.

Moisture in the room – the main driver for mould

The most common practical cause of mould growth is locally increased air or wall humidity. Such moisture peaks can be caused by inadequate ventilation, incorrect heating, tight building envelopes or modernization, such as replacing old windows with new plastic windows without adapting the ventilation concept.

Moisture from the masonry that has not been sufficiently drained away in new buildings or after water damage can also promote mould growth. Cold surfaces encourage condensation, as the wall temperature falls below the dew point of the room air. Short-term peaks in humidity, e.g. when showering, cooking or drying laundry, can cause localized condensation, especially in poorly ventilated or cool areas.

To prevent mould, the relative humidity in the room should not exceed 65-70% and a maximum of 80% directly on the walls. These values can be achieved by regular, short and intensive ventilation several times a day. Cross-ventilation is particularly effective, where humid room air is exchanged for dry fresh air within a few minutes. The right combination of ventilation, controlled room temperature and humidity regulation can create a healthy indoor climate that prevents the formation of new mould in the long term.

Air circulation and practical prevention

If there are no serious structural defects such as a leaking roof or massive moisture ingress, mould can be effectively prevented with simple measures:

• place furniture at a distance from the outer wall
• avoid thick, floor-to-ceiling curtains
• shock or cross ventilation
• air the bedroom in the morning after getting up
• do not allow rooms that are rarely used to cool down completely
• ventilate intensively after bathing or showering
• maintain ventilation systems regularly: clean filters every 2-3 months, replace annually
• empty and clean waste garbage cans regularly

Measures for drying masonry and regulating moisture

For sustainable mould prevention, it is crucial to dry the walls thoroughly. Moisture in masonry can come both from an inadequately dried new building and from water damage, for example from burst pipes. Mineral products such as IsoTex R70 from ClimateCoating® for interior and exterior areas remove excess moisture from the masonry, equalize surface temperatures and reduce thermal stress.

ThermoVital supplements this effect by actively regulating the humidity in the room. Excess moisture is temporarily absorbed and released again in a controlled manner when the air is dry. This stabilizes the indoor climate, prevents condensation at certain points and reduces the risk of mould in the long term. The combination of insulation, drying and moisture buffering offers a holistic solution.

Mould removal and long-term prevention

Visible mould stains on walls and ceilings are a clear warning sign of local moisture problems. Mould grows where moisture and nutrients are present. Temperature and pH value play a subordinate role. Black or brown stains and white mould fluff must be treated quickly and specifically.

Systematic mould removal is carried out in several steps:

1. Treat affected areas: treat mould stains with undiluted Sanosil S010 approx. 5-10 cm beyond the edges while wearing a respirator. The dead mould components must then be removed from the surface by thorough washing, brushing or rubbing. Ideally, a plastic brush should be used in combination with warm water and a cleaning agent so that the dissolved mold components bind in the liquid and are not stirred up. Important: Do not brush off mold components dry and do not inhale.
2. Treatment of room air and possible secondary contamination: with Sanosil S003 furniture can remain in the room. After removal of infested wall coverings, a new treatment with Sanosil S010 while wearing a protective suit and respiratory protection. Important: After the second application with Sanosil S010 do not wash off the surface.
3. Long-term prevention or already preventive: Application of the ThermoVital anti-mould paint, which regulates humidity, reduces localized condensation and effectively prevents new mould growth. The tintable dispersion enables individual colour design in over 100,000 shades for walls and ceilings

Effects on health

Mould indoors is not only a structural risk, but also a significant health risk. Moulds release spores and microbial metabolic products, including mycotoxins, which are absorbed through the air we breathe. This can lead to acute or chronic complaints, especially if you spend long periods of time in contaminated rooms.

Typical signs of health problems caused by mould include:

• allergic reactions and allergy exacerbations
• respiratory complaints such as coughing, shortness of breath or bronchitis
• burning, reddened or watery eyes
• sore throat and irritation of the mucous membranes
• headaches, concentration problems and exhaustion
• skin rashes and fungal and skin infections
• digestive problems
• in severe or long-term cases, lung and cardiovascular diseases

Children, the elderly, asthmatics and people with weakened immune systems are particularly at risk. As the symptoms are often unspecific, mould contamination often remains undetected for a long time. This makes it all the more important to take the first signs of damp seriously and not only remove the visible mould, but also eliminate the causes in the long term.

Conclusion: Mould-free and healthy with ThermoVital

Products such as IsoText R70 in combination with the mould-inhibiting wall paint ThermoVital are extremely effective against mould: IsoText R70 balances surface temperatures and dries the masonry, while ThermoVital regulates the room humidity, prevents condensation at certain points and provides long-term protection against mould. The result is a healthy, comfortable and energy-efficient indoor climate – even in the cold season.

Why rooms feel cold despite heating

Physical causes and solutions with functional paints

The subjective feeling of cold in heated rooms is a widespread problem. It cannot be explained by the measured air temperature alone. Rather, it is the average radiant temperature of the room surfaces that is decisive. Even if the air temperature has reached the setpoint, cold interior walls, ceilings and floors can continue to draw heat from the interior.

The temperature difference between warm and cold air also creates natural convection currents. Radiators make targeted use of this effect: they draw in cooler air near the floor, heat it at the heating surface and discharge it upwards as warm air. The air cools down again along undercooled wall and window surfaces, sinks downwards and thus increases the circulation. This creates noticeable air movement, which removes heat from the human body and significantly reduces the subjective sensation of warmth.

This phenomenon mainly occurs in existing buildings with low thermal insulation, but can also be relevant in new buildings with large window areas or thermal bridges. Cold surfaces also promote local moisture accumulation, which increases the risk of condensation and mold growth. Dry air, as created by heating systems, increases the subjective feeling of cold and can lead to discomfort and an impaired indoor climate.

Building physics context

Cold surfaces lead to a drop in the average radiant temperature and increase the heat emitted by the human body. At the same time, convective air movements occur along these surfaces, which are perceived as draughts and further increase heat loss. The result is a significantly increased subjective sensation of cold, even though the air temperature is sufficient.

Thermal imbalances are also exacerbated by different surface materials in the room. For example, large glass surfaces radiate more heat, while solid wall surfaces can cool down considerably depending on their insulation status. This leads to an uneven temperature distribution, which affects both comfort and energy efficiency, as users set higher room air temperatures to compensate for the perceived cold feeling, which in turn increases the heating energy requirement.

Functional paints as part of the thermal insulation concept

Modern functional paints are a physically based, passive approach to optimizing surface conditions in interiors. Due to their specific material properties, they influence the heat balance, humidity and radiation. This increases the subjective feeling of warmth. In this way, they help to ensure that rooms have a more even temperature and feel more comfortable. They support the stabilization of humidity and can therefore reduce the risk of condensation at certain points. At the same time, they have a positive effect on thermal comfort without the need for additional technical measures or structural interventions.

The ClimateCoating product family for interior walls and ceilings uses a reflective membrane technology with approx. 50 % microfine, vacuumed hollow bodies. These store heat from heating systems or solar radiation and release it back into the room with a time delay. This targeted release of heat increases the surface temperatures, convection currents are reduced and the heat is distributed more evenly throughout the room. ClimateCoating products therefore offer a technically sound, passive solution for a comfortable, healthy and energy-efficient indoor climate.

ClimateCoating products for interior walls and ceilings

Three coatings are available for interior walls and ceilings, each of which meets different requirements:

ThermoPlus – Thermal comfort and moisture regulation

Stores heat from heating systems or solar radiation and releases it again with a time delay. This increases the average surface temperature, reduces convection currents and creates a more even feeling of warmth in the room. The diffusion-open structure also supports moisture regulation and stabilizes the room climate.

ThermoVital – mould prevention and humidity stabilization

Temporarily absorbs excess humidity and releases it again in a controlled manner when the air is dry. This keeps the relative humidity in the optimum range of 45-55 %, reduces localized condensation and reduces the risk of microbial contamination. Particularly suitable for bathrooms, kitchens, bedrooms and old buildings prone to moisture.

Lumen – light reflection and even heat distribution

Increases light reflection in the interior and ensures an even distribution of radiant energy. This not only increases brightness, but also supports heat distribution and indirectly increases the subjective feeling of warmth. Lumen is ideal for bright rooms or rooms with large window areas.

Improving thermal comfort

The combination of these active principles leads to a significant improvement in the indoor climate. By increasing surface temperatures, reducing convection currents and stabilizing humidity, thermal comfort increases significantly. At the same time, a more even distribution of heat between the ceiling and floor areas is achieved. This prevents unpleasant temperature differences and makes cold feet a thing of the past. Under real conditions of use, heating costs, electricity and energy can be saved by up to 30 % without the need for additional technical systems or structural interventions. This significantly increases the feel-good effect and reduces heating costs in the long term.

Functional paints therefore offer an effective way of optimizing the indoor climate and sustainably reducing heating energy requirements – especially in existing buildings, apartments, offices or public facilities where structural measures are only possible to a limited extent.

Sustainable thermal insulation without additional energy

In contrast to active heating or ventilation systems, functional colors have a purely passive effect. Winter thermal insulation is provided solely by the physical properties of the materials. The durable surfaces of ThermoPlus, ThermoVital and Lumen also reduce soiling and extend renovation intervals, which also saves resources in the long term.

Conclusion: A feeling of warmth is created by radiation

Anyone wondering why a room seems cold despite the heating being on should therefore consider not only the air temperature, but also the surface quality of the walls. Energy-efficient functional paints offer a passive, sustainable solution that improves the indoor climate, reduces heating costs and regulates humidity at the same time – without any structural interventions. This makes winter in your own home not only warmer, but also more pleasant and healthier.

Intelligent protection against the winter cold

Winter thermal insulation in the interior: energy-efficient solutions with functional colours

Winter thermal insulation is a central component of energy-efficient building planning. The aim is to minimize heat loss in the cold season, reduce heating energy requirements and at the same time ensure a high level of thermal comfort indoors. In addition to insulation, windows and heating technology, interior measures are becoming increasingly important. One such measure is the use of modern functional paints for interiors.

Definition and building physics context

Winter thermal insulation refers to all structural and material-related measures that reduce heat loss from heated rooms. It is not only the U-values of the building components that are decisive here, but also the interaction of surface temperatures, air movement and moisture behavior in the interior.

Cold wall surfaces lead to convection currents, an increased heating requirement and a subjectively cooler room feeling, even if the room air temperature is sufficient. Winter thermal insulation therefore aims to achieve an even temperature distribution and reduce thermal imbalances.

Interior wall paints as part of the thermal insulation concept

The surfaces of interior walls have a significant influence on the heat balance of a room. Conventional emulsion paints have hardly any heat-regulating properties. Energy-efficient functional paints such as ThermoPlus from ClimateCoating® use physical effects to retain heat in the room and release it again in a controlled manner.

The reflective membrane technology used is based on micro-fine, vacuumized hollow structures. After application, these form a continuous, heat-reflecting layer. This membrane stores thermal energy from heating systems or solar gains and reflects it back into the room with a time delay.

Improving thermal comfort in winter

By storing and evenly releasing heat, the average surface temperature of the walls increases. This reduces convection currents on cold surfaces and compensates for temperature differences between the floor and ceiling areas. The result is significantly improved thermal comfort, as people react not only to the air temperature but also to the radiant temperatures.

In practice, this effect can significantly reduce heating energy requirements. Under real conditions of use, heating energy savings of up to 30 % are possible without the need for additional technical systems or structural interventions.

Moisture regulation as part of winter thermal insulation

Another important aspect is the humidity behavior of indoor spaces. Dry heated air in winter often leads to discomfort, increased dust levels and stress on the respiratory tract. At the same time, cold wall surfaces promote local moisture accumulation and mold growth.

Functional colors like ThermoPlus are open to diffusion and moisture-regulating. They temporarily absorb excess humidity and release it again when the room air is dry. This stabilizes the relative humidity at around 55%, which is considered optimal from a building physics and hygiene perspective. At the same time, the formation of condensation on wall surfaces is reduced.

Sustainable thermal insulation without additional energy

In contrast to active heating or ventilation systems, the functional color works purely passively. The winter thermal insulation is created solely by the material properties and physical principles of action. This makes ThermoPlus particularly interesting for use in existing buildings, homes, offices and public facilities where structural measures are only possible to a limited extent.

In addition, durable, anti-electrostatic surfaces help to reduce soiling and extend renovation intervals. This not only saves energy, but also reduces the consumption of resources in the long term.

Conclusion: Functional colours as a clever addition to thermal insulation

The thermal insulation of modern buildings in winter requires a holistic understanding of building physics and indoor climate. Energy-efficient interior wall paints such as ThermoPlus are an effective addition to classic insulation measures. Thanks to heat storage, even heat release and moisture regulation, they improve both energy efficiency and the quality of indoor living.

Functional colours thus make an important contribution to sustainable building, reduced energy consumption and healthy living – especially in times of rising heating costs and growing demands for climate protection.