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As the nights draw in and the temperature drops, one problem we see time and time again is condensation within properties. As people, quite reasonably try to keep the warmth in and the cold out, adequately ventilating properties seems to take a back seat to comfort. Management of any property you live in is crucial to ensure that day-to-day life is as happy as can be. We take a look into condensation as a problem, how it occurs, and how to manage and avoid the issue altogether.


What is Condensation, and where does it come from?

Condensation, simply is water vapour from the air, collecting as droplets on a cold surface. As can often be seen on windows and in cars. The water vapour in the air occurs naturally and can be found everywhere. It almost goes without saying, that as the weather gets colder and indeed wetter (as is usually the case in Britain), the amount of water in the air increases. This isn’t in itself a problem, but it can become so if water levels are allowed to build up inside properties.

To further add to the problem, the average person loses around 800ml per day (24 hours) through the skin and through breathing, before taking into account any exercise. If someone is spending a large amount of time indoors, this water stays inside as well. Or, simply taking 8 hours of sleep, this would equate to over 266ml, whilst sleeping alone! If this water vapour isn’t removed from within a property, it will eventually condensate against cold surfaces, which can often be seen as moisture on the inside of windows. And over time, sitting condensation can turn to mould, which is not only unpleasant but can also lead to health problems and damage to the property itself.

One area in which this can be a real problem is within HMO properties. To conform to the fire safety standards that are in place, bedrooms within shared houses have to have fire doors on them, fitted with intumescent strips. This creates a seal in the event there is a fire to protect those within the bedroom. However, it also allows for next to no airflow when the door is closed, meaning the water vapour has nowhere to go, added to the fact that a lot of houses now have lovely double-glazed windows, and you get a situation where the moisture has nowhere to go but to the coldest part of the room.

Another reason for excessive moisture building up in a room is where a person is using a radiator to dry clothes.  Jeans and towels, in particular, hold a lot of water immediately after they have come out of a washing machine, again, this water has to go somewhere and if the windows and fire doors are shut, the cold walls or inside of the window pane is the obvious place. The drying of clothes in this way isn’t a problem but will reduce the amount of heat into the room and increase the amount of water. So, considerations will need to be made to heat and ventilate further, to clear this. Houseplants, whilst popular at the moment, will also bring additional moisture into the air in a room, so will also need consideration as to how that moisture will clear.


But if water vapour is everywhere, how can we stop this problem?

The first point to help here is to ensure the property is properly heated.  A building needs to be at a certain temperature to avoid condensation where possible.  It’s very clear that energy bills are expensive, but if the other option is to have a house that is attracting condensation, then the best option is clearly to heat accordingly.  Ventilation is the second factor and coupled with heating the property adequately, will alleviate the vast majority of condensation issues.  You can quite easily see in the morning if you have condensation running down your windows, that you will need to open your windows and ventilate, even on a cold day. This will allow any water vapour out of the property before it has a chance to condensate anywhere.

Another great idea is to be sure to use any mechanical extraction in the property frequently. This means ensuring any bathroom fans are on whenever a shower or bath is on, and making sure to use the cooker hood when cooking. This makes sure that any excess moisture introduced into the building by the steam generated by these activities is removed as quickly as possible. It will also help to ensure the kitchen and bathroom doors are closed when steam is being generated.


It is important to note however, that condensation is different in many ways to rising damp and water ingress when water enters a property through the fabric of the building. This is usually characterised by brown tide marks on walls, or wall coverings coming away from underneath. However, this added moisture within a property can also bring condensation problems with it. But that’s a topic for another blog!

The earliest sign of any condensation build-up within a property is usually water collecting on windows, so if you do begin to see that, be sure to make a concerted effort to heat and ventilate the house, in order to clear the problem before it develops. Serious build-ups of condensation can cause mould in cold spots of rooms, including in wardrobes and on the items inside. This can lead to damage to the property, damage to your belongings, and may even lead to health problems (as well as looking really unpleasant).

If you have any questions about this topic or would like to speak to a member of our team about it, get in touch, to

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