Removing the fungus from wood and further prevention
First you can rub mold using water soap and brush. You can also try the most ordinary chlorine -based bleach, mixing it with the same amount of water. Oxygen bleach can also help in this situation, but then you will need to rub the places with mold with a hard brush.
The most important satellite of mold is moisture. By virtue of this, it is impossible to keep the wood moist, it always needs to be immediately dried. If your house is produced in wet conditions, then never allow builders to close the wood in a humid state. In any case, mold must be immediately removed before winter heating is produced, because a person living in such a room will suffer from the dispute hidden there.