Black mold stains on the wood are not only visually disturbing, but also pose a health risk. You can find resources, instructions and preventive measures here.

In a nutshell

  • Sanding is often required
  • Chlorine, vinegar essence and fungicide are possible aids
  • Stains are caused by mold
  • Humidity plays a crucial role
  • sustainable prevention is easier than removal

causes

Black mold stains can show up on wooden furniture both indoors and outdoors. They occur more frequently outdoors than indoors, since more favorable factors occur here. These include, among others:

  • frost
  • rain
  • snow
  • sun or UV radiation

This can make the material brittle and moisture or liquid can penetrate. Appropriate protection is therefore required. Otherwise, the wooden material acts as an ideal breeding ground for mold. This is exactly what causes black mold stains. In addition to the causes already mentioned, other favorable factors are also possible. These include dirt such as:

  • foliage and needles
  • pollen and petals
  • other dirt
  • bird droppings

All of these substances ensure that the mold spores can penetrate deeper into the wood and initially spread unnoticed. This leads to damage that only becomes visible through mildew stains.

prevention

Prevention is better than cure, they say. This also applies to mold stains on the wooden furniture. There are some measures that can prevent their formation. These include:

  • choose the right type of wood: Soft wood species such as spruce and pine are more susceptible to mold and are therefore not suitable for outdoor use. Hardwoods such as teak, Douglas fir, oak and larch, on the other hand, are less sensitive and are resistant to mould. The selection should therefore be considered, especially outside or in damp areas.
  • air: Appropriate ventilation and adequate clearance from walls and other furniture are essential to avoid mildew stains. This is the only way for the wooden surface to dry properly. Proper ventilation is just as important. Therefore, it should be warmer inside than outside. Otherwise, warm moist air can penetrate into the cooler room and condense on the surfaces.
  • use appropriate means of protection: Lacquer, glaze, wax and oil can be used to protect the natural material. These remedies must be applied at regular intervals to remain effective. This is especially true for the outside area.
  • subdue or cover: The fewer temperature fluctuations and the less precipitation the wood is exposed to, the lower the risk of damage and mold.

Utensils & Means

If black mold stains have already formed, appropriate means must be used. Suitable for combating mold are:

  • chlorine cleaner
  • vinegar essence
  • fungicides

You will need the following utensils:

  • bucket
  • a grinder and sandpaper
  • paint brush
  • spray bottle
  • water

Protective measures & means

Handling an appropriate tool and the mold itself can endanger your health. The eyes, respiratory tract and mucous membranes are particularly sensitive to it. Possible complaints are:

  • red, watery eyes
  • increased secretion production
  • to cough
  • a headache
  • nausea

The right safety precautions are therefore crucial. Are needed:

  • good ventilation
  • gloves
  • safety goggles
  • protective mask

Superficial infestation

Various steps are required to remove the black mold stains from the natural material. It refers to:

  • Let furniture dry: The wooden furniture must be completely dry before it is treated. Otherwise, the mold can spread again in a short time, despite all efforts. For this purpose, for example, heat radiators can be used.
  • Apply detergent: Vinegar essence, chlorine or fungicide are often sufficient for small and defined stains. They can be applied with a brush or sprayed on. It is important that the agent can be absorbed well and gets into every crack.
  • Wipe off: After an appropriate exposure time of about 30 to 60 minutes, the stain is sprayed again and then wiped off. It is best to use cellulose for this, which you can dispose of with household waste. Because the ingested spores may not have been completely killed and could therefore pose a health risk.

Notice: If the stains have not disappeared after that, the application must be repeated. This can be necessary several times.

Treat deeper infestations

If the mold has already penetrated deeper layers of the wood, simply soaking and wiping is no longer sufficient. A little more is then required for the removal. The following guide shows how it works.

  • Let furniture dry: The affected piece of furniture must be completely dry. Again, it is advisable to use a radiant heater, for example. A construction dryer is ideal.
  • grind down: The affected layers are removed manually with sandpaper or a grinder. To avoid unevenness, the surface should be checked again and again with a spirit level. In addition, of course, the entire surface should be included when sanding.
  • Apply funds: Chlorine, vinegar or fungicide can be used. The wood can be impregnated with it.
  • Remove excess liquid: After the exposure time, you should wipe off excess liquid. Pulp is best for this because it is absorbent and can be easily disposed of.

If black mold stains appear again, you must repeat the application. Only in very severe cases is it better to discard the wood. Otherwise, serious consequences can occur, especially indoors.

Tip: Dispose of the sandpaper afterwards. In addition to dust, this also contains mold spores. If used again, these could be distributed.

frequently asked Questions

Prevent black mold stains: is a tarpaulin enough?

Covers and tarpaulins are often used to cover outdoor furniture. On the one hand, these provide protection against direct contact with precipitation and protect against UV radiation. On the other hand, they can also trap existing moisture and thus promote mold. Storage in a dry and frost-free room is therefore better.

Does the furniture need to be cleaned before storage?

Yes, that makes sense in any case. This removes dirt and thus also spores, which reduces the risk of mold infestation.

How often does the wood protection have to be renewed?

There is no general answer to this. Because the frequency depends on various factors. These include the type of agent and the influences to which the piece of furniture or, for example, the terrace is exposed. Varnish therefore usually lasts longer than glaze, oil or wax. However, these can be completely sufficient for wood indoors and, due to their properties, even contribute to a pleasant indoor climate. When making your selection, always pay attention to suitability and the information provided by the manufacturer.

Category:

Garden maintenance