Preventing Damp During Autumn and Winter

During autumn and winter when the weather starts to cool it is important to take steps prevent minor issues with condensation becoming more serious damp and mould problems.

When the temperatures outdoors are colder, it creates a temperature gradient around windows and exterior walls that reduces the amount of water vapour the air can hold and leads to condensation forming on windows and walls. Although domestic heating keeps the middle of rooms and the areas around radiators warm, where there are cold pockets you are most likely to see damp patches start to develop.

How condensation causes damp

Condensation forms when the amount of moisture in the air is too high. At a 20C room temperature air holds around 17grams of water per cubic metre, but as the temperature drops to a nighttime 10C, the amount of water falls by half to around 9grams per cubic metre of air. The remaining water forms droplets on a cold surface as condensation.

On non-porous materials like windows and bathroom tiles, condensation can simply be wiped away from the surface or simply allowed to evaporate as temperatures rise, however if the condensation forms on a porous surface such as a wall, the water will soak in and start to saturate the underlying plaster causing a damp patch.

Why damp is a problem

Over time, damp patches cause plaster to crumble, and this results in paint and wallpaper peeling away to leave an unpleasant mess. Damp affected plaster needs to be removed and replaced which can be a costly process.

A worse problem because of damp is the growth of mould. Mould enjoys in damp conditions, especially where there is limited air flow such as behind furniture or in cupboards. As patches of mould grow, they release large numbers of spores into the air to spread. These can aggravate allergies and the symptoms of asthma or other respiratory conditions. Some mould species such as Stachybotrys Chartarum (Toxic Black Mould) release chemicals called mycotoxins that can result in serious illness.

Dealing with damp, or better still, preventing it from occurring in the first place will stop mould from growing in your home and protect your house from damage.

Stopping damp

The most effective way of preventing damp is to stop condensation.

Many day-to-day activities contribute to the amount of moisture in our homes. This includes steam from cooking, bathing, and drying clothes. You can take steps to reduce the amount of water vapour getting into areas where it can lead to damp by keeping kitchen and bathroom doors closed when in use, and opening windows to vent as much moist air outdoors as possible.

During the winter months, you may not want to leave windows open for long periods, so extractor fans are usually needed in bathrooms and kitchens.

Modern extractor fans such as the EnviroVent Cyclone 8 are highly effective in reducing condensation and damp because they feature a humidity sensor.  This measures the amount of moisture in the air and automatically adjusts the power levels in the fan to expel humid air before condensation can form.

Find out more

If you are worried about the effects of condensation and damp in your home this winter, please contact us today to book a free home survey.  Our local ventilation specialist will identify any damp and condensation issues in your home and provide advice about the best thing you can do.

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