Table of contents:

Avoid mold: the most important measures
Avoid mold: the most important measures
Video: Avoid mold: the most important measures
Video: How To Prevent Mold in Your Home: Proven Mold Prevention Tips for Homes 2023, February

The best way to avoid mold is to air it regularly. Learn how to avoid mold and what you can do if it does show up here.

Molds are found in at least every tenth German apartment. Black spots grow on the walls and the air smells musty. So far, scientists have identified 100, 000 species - more than 100 of which are proliferating in the living area. The metabolites of the mold can harm our health and trigger allergies, asthma, chronic diseases of the respiratory tract and sinuses.

Causes of mold

The fungal spores are everywhere, but begin to grow on a damp surface. Where does this moisture come from? We produce them by breathing and sweating, cooking and showering. To clarify: A four-person household produces about ten liters of water every day through evaporation - a large cleaning bucket full of water. The room air absorbs this amount as invisible steam, which later later liquefies on cold surfaces.

The air can absorb a certain amount of water vapor per cubic meter - the warmer the more. Once the maximum amount has been reached, experts speak of saturation: per cubic meter, this is up to:

  • 1.4 grams at -15 degrees Celsius
  • 4.8 grams at 0 degrees Celsius
  • 12.8 grams at +15 degrees Celsius
  • 17.3 grams at +20 degrees Celsius
  • 23.1 grams at +25 degrees Celsius

How to avoid mold

You can avoid mold first with some important behaviors. Mold only grows on a damp surface, so you only need to keep the walls, ceilings and floors dry. The easiest way to do this is through proper heating and ventilation. If rising water dampens the walls, if there is a leak in the pipe network or roof, then these construction defects must be eliminated. Painting with conventional anti-mold paints pollutes the indoor air with fungicides or biocides and only helps for a short time. Why? Because we are less likely to deal with moisture that penetrates somewhere, but mostly with moisture that is contained in the room air and is reflected on the walls.

Ventilate to prevent mold

Regular and adequate ventilation is the best way to prevent mold. Up to half a liter of liquid disappears from a 20 square meter space per ventilation action. With the used, warm air, moisture pulls outside and cold, therefore dry air flows inwards. It absorbs a lot of moisture when heating up and the room becomes drier. If you exchange your old windows for new ones, you have to pay attention to "conscious" ventilation. The old, leaky windows, unlike the new ones, ventilated all the time, unnoticed by joints and crevices. Alternatively, you can also have a ventilation system installed.

How long should you ventilate?

The best way to renew the air in the room is to "ventilate it": Open two opposite windows completely for about five minutes - one minute renews the air in the room rather than not at all! A five to ten minute surge ventilation also ensures a significant improvement in the air in the room. Here you only open one window - also completely. A tilted window is called night ventilation. Here you should leave the window open for at least half an hour to experience an improvement in the indoor air. However, an hour is better.

It is best to ventilate horizontally, three to four times a day. The colder it gets outside, the faster it goes. If you tilt the window, the room air exchange takes a long time - moreover, you often forget that the window sash is tilted. In 45 minutes, the window reveal cools in winter so that moisture condenses there: mold grows.

How long to ventilate?

month Ventilation time
December, January, February every 2 hours 4-6 min.
March, November every 2 hours 8-10 min.
April, October every 2 hours 12-15 min.
May, September every 2 hours 16-20 minutes
June July August every 2 hours 25-30 minutes
Beschlagene Fenster
Beschlagene Fenster

A household of four produces about ten liters of water a day through evaporation.

Photo: iStock / bazza1960

Relative humidity

Humans can feel heat and cold, but they don't have a fine sense organ for moisture. He only feels the effects of the humidity below 30 percent and over 70 percent, namely as thirst or sweating. A relative humidity in rooms between 40 and 60 percent is ideal for us humans. At over 60 percent, we have to intervene to prevent mold and mites. We can find out the exact relative air humidity with a moisture measuring device.

Measure air humidity

Analog or digital moisture meters (hygrometers) and thermometers are available separately or in combination, from around ten euros in department stores, hardware stores and in the electrical trade. Electronic devices often react sluggishly. Make sure that the devices have an adjusting screw for adjustment, since the setting can change during transport. To readjust, wrap the hygrometer in a damp cloth. If the device does not show about 95 percent room humidity after an hour, you must correct it using the adjusting screw.

Control of temperature and humidity

Insulation is necessary because thin walls are cold on the room side and the insulation keeps the surfaces warm. House corners cool down particularly quickly, since the ratio of inner to outer surface is very low - little heat is absorbed inside, but a lot of heat is emitted outside, due to a large area (table). It is therefore very important that you monitor the temperatures and the humidity. It is also advisable to buy a surface thermometer.

Temperature gradient

Room 20 ° C, outside -10 ° C straight outer wall Outside wall corner
Wall 24 cm thick 13.8 ° C 6.2 ° C
Wall 24 cm + 4 cm insulation 17.6 ° C 13.7 ° C
Wall 24 cm + 10 cm insulation 18.2 ° C 15.3 ° C

Not a pretty sight: molds are found in at least every tenth German apartment.

Photo: iStock / rkankaro

Furnish rooms properly and thus reduce the risk of mold

If possible, do not place any pieces of furniture on the outer wall. So the air circulation is not disturbed. If you cannot find another place for furniture, the room air must at least be able to circulate. To do this, remove the air-blocking skirting boards and keep a minimum distance of six centimeters between the furniture and the wall.

Controlled ventilation

A ventilation system draws fresh air into the house and keeps dirt out. One pipe system transports fresh air in, another takes used air out. Both air flows intersect in a box without mixing: the warm exhaust air temperates the cold fresh air. If the supply air is cleaned by a filter, noise, as well as soot, dust and pollen, remains outside. Electro filters hold 95 percent of the air particles.

Controlled ventilation systems ensure that the exhaust air leaves the house, but not the heat. You save a lot of energy and heating costs. This also appeals to the state, which financially supports the installation of apartment fans in low-energy and passive houses as part of the Energy Saving Ordinance (EnEV).

If you couldn't avoid the mold

To remove mold, the procedure is different depending on the level of infestation and the area affected. Infested elastic joints must be completely removed and replaced. Treat areas in the early stages of mold with three to four percent vinegar essence, with alcohol-based cleaning agents (80 percent ethanol), with hydrogen peroxide (five to ten percent), with soda solution (5 percent) and, if necessary, with high-percentage alcohol or a salmon thinner. After treatment with these agents, wipe carefully, damp and then dry. It is best not to use spray bottles, but to rely on your muscle strength. When working against or with mold, you should definitely wear a face mask.

Printable checklist against mold

Done The most important tips in the area …
1. Temperature: Sleeping cool is healthy. Below 15 degrees

Celsius, however, the room temperature must not drop.

2. Ventilate: If possible, the air should be exhausted every two hours


3. Dry heating: window open, cold air in: it takes a lot

Damp. Repeat the whole thing several times from the beginning.

4. Condensate: Do not heat the cool bedroom by

you leave the door to the warm living room open -

Risk of moisture damage.

5. Regulation: Thermostatic valves react to the

Room temperature. Therefore turn off when airing. function

do not interfere with long curtains.

6. Ventilation time: Open opposite windows, effectively

ventilate: five minutes are enough. Not in the tilt position for long

to let.

7. Radiator: do not block heat emission: no furniture

in front of it, do not mount any cladding. Wall niches

you can insulate cheaply from the inside.

8. Basement: only ventilate at night in summer, otherwise a lot will come

Moist pure.

9. Tiles: Wipe in the bathroom immediately after showering, before

especially if it has no window.

10. Insulate: Anyone more than ten percent of the total

Component area changes, must meet the requirements of EnEV 2009


Popular by topic