When water moves through holes in a leaking roof mold can easily grow in the ceiling since it is regularly fed with what it needs to thrive.
What causes mold on ceiling in bathroom.
When moisture that is produced inside your bathroom comes in contact with the ceiling and becomes its resting place condensation begins.
Water coming out from basin bathtub and shower will create wet surfaces that are claimed by black mold as the place for it to live in.
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That is the reason why condensation is very common in cold surfaces.
Aside from the water supply creating the fungus infestation in the ceiling the steam evaporation is another cause you can t look down.
Any water that doesn t drain properly and sits in the drain creates a moisture problem.
Poor ventilation is one of the most common causes of mold and mildew in bathrooms.
Warm temperature in most cases the bathroom ceiling becomes an ideal place for black mold to grow due to condensation.
Mold caused by blocked bathroom drains drains which do not drain water properly can also contribute to mold growing in bathtubs showers or basins.
I recommend replacing the fan with a constant flow unit such as the panasonic whispergreen fan.
This is the major cause of mold growth in bathroom ceilings.
The effect of cold air on the outside of walls and warm air on the inside can cause condensation.
Most homeowners claim that it is the primary reason of the black mold emergence.
In addition to water supply another cause of black mold infestation in the bathroom is related to the steam evaporation.
Once the water comes out and gives rise to the soggy surface the black mold in bathroom ceiling conveniently disperses.
When warmer more humid air meets the cold wall condensation forms contributing to mold problems.
The main cause of mold on a bathroom ceiling is a broken or ineffective exhaust fan.
Any environment like this where water is collected and stands for long periods can easily grow mold.