What is Condensation?

Condensation essentially is when moisture is absorbed into the warm atmosphere of a property and then as the property cools down the moisture condenses on cold surfaces such as on windows or windowsills.

Condensation is one of the most common forms of dampness found in buildings and can lead to all manner of problems from peeling wallpapers through to unhealthy living conditions and mould growth issues.

The reason that problems with condensation are on the increase is because of increased standards of insulation, double glazing and draught proofing making properties more airtight and resulting in moisture laden air staying within the property.

Accredited to

Nic Glover

Branch Manager and Waterproofing Design Specialist CSRT CSSW
North East

What Causes Condensation?

Warm air can hold more water vapour than cold air – the warmer the air the more water it can hold and conversely the cooler the air the less it can hold.

Thus, given this fact, it becomes evident that if warm moisture-laden air is cooled there will become a point at which the air is cooled to such a level it can longer hold the moisture present.

It is at this point that the excess moisture starts to change from its vapour state into a liquid and effectively drops out of the air – this is what we see as condensation.

In practice, the effect is seen when moisture-laden air comes into contact with a cold surface, the coldness cools the air to an extent where it can no longer hold the excess water and it, therefore, falls out as liquid water (condensate) on the cold surface.

Black spot mould in bedroom

Condensation is very much a seasonal problem, occurring during the colder months –usually from October to April. During the winter, ventilation within a property is usually low (due to windows and doors being closed and an increased awareness of draught-proofing).

This allows the build-up of water vapour in the house, which, in some cases, is sufficient to cause condensation.

The build-up of moisture from our day-to-day life includes activities such as boiling the kettle, drying clothes inside, taking a shower and even breathing.

By and large condensation is noticeable and easy to spot when it forms on non-absorbent surfaces for example windows or tiles. On more absorbent surfaces, however, it may go unnoticed until mould growth or damage to decorative finishes occurs.

The mould growth is normally associated with a musty smell. It is at this stage that you may need advice on controlling condensation within the property. For more information about what causes condensation visit our causes of condensation page.

Did you know?

“An average family of four will produce 2­3 litres of water per day.”

Signs of Condensation

How to Spot Signs Of Condensation?

The obvious places for condensation to occur is on windows, cold walls and floors, but it can also occur in roof spaces and in sub-floor areas where there is a timber suspended floor.

Where there is a suspended floor condensation may also lead to ry rot or wet rot developing in floor timbers.

The most common sign of condensation, as we all know, is water collecting on the inside of windows or on the window sill. This easily recognisable sign indicates that there is a lack of ventilation in the property and moisture laden air needs to be dispersed.

However, perhaps the most common sign of condensation is mould growth. This is usually seen as 'black spot' mould but green, yellow and white moulds may also develop depending on the conditions and the particular surface.

There are proven health hazards associated with moulds, the most common being a trigger factor for asthma. However, it appears likely that in most healthy people only heavy, persistent moulds may potentially cause a problem although some people may be particularly sensitive.

The list below shows what signs to look for when trying to stop condensation:

  • Water droplets collecting on a window or windowsill
  • Black mould may begin to grow on walls, surfaces and carpets
  • A damp musty smell
  • Peeling paint or plaster
  • Mould on clothes and fabrics

EnergySaver Sensamatic Kitchen Fan

Condensation Control and Treatments

When tackling condensation it is important to target the source of moisture in the air, this then ensures that moisture cannot grow.

Condensation is inevitably derived from normal living activities such as washing, cooking and bathing.

Normally this moisture is vented away but in some cases, this isn't apparent, double glazing, draught exclusion, blocking of air vents and chimneys all restrict the venting of moisture laden air. This occurs especially from those areas where most water is produced such as bathrooms and kitchens.

Improving the ventilation in a home is key to allowing moisture-laden air to exit the property quickly. This can be achieved by adding mechanical ventilation such as adding kitchen and bathroom fans.

There are other few simple treatments to help control condensation levels within properties:

  • Improve the heating and insulation within the property.
  • Prevent excess moisture in the air spreading (For example shut bathroom and kitchen doors).
  • Avoid if possible using portable or LPG gas heaters. These types of heater are the cause of many condensation problems in properties.
  • Using dehumidifiers will only help control the symptoms of the problem and not the actual root cause of the condensation problem. They can also be very intrusive and noisy as well as costly to run.
  • Having a positive pressure ventilation system installed will control and remove the stale air from the property.
  • Using bleach and other such products to remove the mould does not work as it does not kill the mould spores. Using a professional mould eradication kit will kill the mould spores for good.

    A mould eradication kit is ideal for properties with that have a mild condensation mould problem. The kit includes everything needed to remove mould from surfaces and alleviate the unsightly problems of mould.

Timberwise mould removal kit

Mould Removal Kit

Are you looking for a fast, simple and cost effective solution to solve your condensation mould problem? If so, you need a Condensation Mould Kit. Condensation Mould Kits are simple to use – so much so that you can even apply the treatment yourself.

We have a range of Condensation Mould Kits which come with simple ‘step by step instructions and contain everything you need to eradicate condensation mould problems from your property.

A Mould Eradication Kit

Get in Touch With a Condensation Specialist

It is important to contact a condensation specialist who can provide specific advice for providing solutions to control and eliminate condensation along with persistent problems associated with condensation such as mould growth.

You can contact our condensation specialists by calling 0800 288 8660 or you can request a survey online. Having a damp survey through Timberwise will be able to identify the full extent of the problem and determine whether further condensation treatments are necessary.

Request a survey

Worried about condensation? Call 0800 288 8660 or