What Causes Damp in Bathrooms

Your bathroom is one of the biggest sources of condensation in your home. Not only do you release large amounts of steam into the air during every bath or shower, but you also create additional water vapour by drying towels on radiators and running taps to wash your hands or shave.

If the water vapour released when using your bathroom is not properly ventilated using an extractor fan, it forms condensation that will eventually soak into walls and woodwork to create damp patches, which, in time, can provide the conditions needed for mould to grow.

How Much Condensation Does Bathing Cause

The amount of condensation that your bath will create is dependent on many factors. The amount of water vapour that rises from the bath will depend on the temperature of the water and that of the surrounding air, and the amount of airflow that is present in the room. A hot bath on a chilly day will feel luxurious, but because the cooler air is able to hold less moisture, more condensation will form on walls and ceilings.

The same is true with showers, although a sealed cubicle can make an enormous difference to the amount of steam which escapes. Typically, showers are shorter than baths and use less water, but that water is sprayed from a height, and we tend to wash more actively when showering, which can move the air around more and carry the steam around the bathroom.

Stop Condensation from Causing Bathroom Damp

Thankfully, there are things you can do to reduce the risk of damp and mould forming in your bathroom because of condensation from bathing.

If you start filling your bath with cold water and then warm it up rather than filling with hot and using cold water to adjust the temperature down, there is less time when the bath is at its hottest temperature. This means that less steam is formed.

Ensuring that your extractor fan is switched on throughout your bath or shower and leaving it running for thirty minutes after you have finished will ensure that all the excess moisture can escape from the room rather than forming as condensation. Modern bathroom extractor fans can include a humidity sensor that will adjust the power levels and reduce the amount of water vapour in the air more quickly which reduces the risk of condensation.

When bathing it is sensible to keep the bathroom door closed to prevent steam escaping into other parts of the house, but once you have finished in the bathroom, if your extractor fan is working properly, leaving the door slightly ajar will help the airflow through the fan. The slight negative air pressure in the bathroom while the fan is running will prevent steam from escaping.

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Find out more

If you have discovered damp patches, or mould in your bathroom, it is likely that condensation is the cause. If you have insufficient ventilation in the bathroom, the problem will only get worse over time, so it is important to act quickly to avoid expensive repair bills. Speak to one of our local ventilation specialists. They can visit your home to conduct a free home survey where they will identify the causes of condensation damp and mould and provide you with advice about the best way of dealing with the problem. Simply enter your postcode below to find your local expert and get rid of condensation for good.