Best ways to combat condensation on your windows

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       Who showers without opening a window in the bathroom? Who has blocked up every ventilation panel and trickle vent, to keep out the draughts? Who insists on drying masses of washing on radiators? If any of these actions sound like you then condensation is likely to be your bedfellow this winter.

There are three main factors governing condensation:

  1. Water vapour content of the air
  2. Inside room temperature
  3. Outside temperature

The last one is beyond our control. First and second however are dependent on our normal living conditions – usually with sophisticated heating systems, warmer rooms, less ventilation and fewer air changes. As a result water vapour produced by our regular living has no longer where to escape.

Remember, there is always moisture in your home. humidifier producing moisture

It usually settles at between 40-60%. The problem only happens when your internal room temperature rises as the outside temperature falls. Typical case of ‘brrr, chilly weather let’s flick on the central heating.’ The moisture in the air turns to liquid as it hits a cold wall or window and hey presto you have water on surfaces. You might see condensation on your windows, walls, doors or between window panels.

While a touch of water may sound quite innocent, if condensation isn't managed promptly it can end up causing damage to the paintwork, curtains, wall coverings, window fittings and even mould on your walls and around your windows. Not just is this stuff ugly, but having a considerable measure of it in your home can lead to certain health issues, such as sinus problems, skin rashes, and even bronchitis.

The location of the condensation always points to the solution.

It is important to note on which side of the glass it appears; the area points to the cause. Condensation on the outside of the outer glass is very normal and shouldn’t be causing any worries.

Condensation on the room side surface of the internal glass pane implies that the temperature of the glass surface is too low given the water vapour content of the air in the room. In this case simple ‘around the house’ lifestyle changes can help a lot. 

If it forms within the cavity of a hermetically sealed unit this usually points to a failure of the seal. Where there’s a secondary glazing some degree of air migrating from the room into the cavity can be expected. In this case attention should be directed to seals and joints – are they airtight enough? However if it forms when the sun is shining, it requires further inspection, a bit of DIY or replacement of the unit. As it usually implies that something in the air space contains moisture. Secondary panel could be removed, all desiccant discarded, holes and cracks and wooden surfaces sealed with an appropriate sealer and then secondary pane could be replaced – making sure that all seals and joints are as airtight as possible. 

Double glazing helps reduce condensation.

Double glazing acts as an insulator, intended to reduce the loss of the heat and improve energy efficiency of your home.  In normal conditions the temperature of the room side glass panel will be higher, so the introduction of the air cavity and second window panel reduces the likelihood of condensation happening when the warm air in the room comes into contact with the surface of the window. That wouldn’t be the case with single glazing.

It’s good to remember that even double glazing can not reduce when rooms aren’t adequately heated or there’s very little heat to retain. The best way to prevent it happening is to use double glazing in conjunction with heating and controlled ventilation.

8 Simple Ways to prevent condensation in your home this winter.Young girl looking through the window when raining

There are however some very simple and good practices to help you maintain a good water moisture balance in your home reducing the possibility of condensation happening. Follow these top tips and you will notice an immediate difference.

  1. Ventilate your home - we may well be tasked with insulating our homes but we do need airflow; so open trickle vents or windows during the day wherever you can. Two sleeping adults can produce well over a pint of water between them overnight so having some ventilation in the room will help and is much healthier too. Bathing or showering causes masses of steam. You’ll now how much steam fills the room and the water left when the steam condenses.  So, always close doors and open windows even in the depth of winter. Leave them open for 20 minutes after you have finished bathing to clear any excess steam.
  2. Fit an extractor fan, hoods over cooker or other equipment producing steam.
  3. Vent as much as possible if your property is new, otherwise you will be adding even more moisture by living there. New properties are filled with moisture. Be aware a building may have about 1500 gallons of liquid in it. Think of all the wet cement, plaster, paint and so on that was used in its construction.
  4. Consider double or triple glazing if you don’t already have it. This will mean the internal window will be warmer and less condensation will form. It basically acts as an insulator stopping heat from escaping from inside the building. If you are seeing condensation between double-glazing panes it may well mean a seal is broken and it needs replacing.
  5. Draught proof your internal doors and keep them closed to stop migration of the moist air between rooms.
  6. Avoid paraffin heaters that cause excessive moisture.
  7. Consider using a dehumidifier especially in areas where there is little natural movement of air. The aim is to change the air in the house often.
  8. Did you consider your plants? – indoor plants are quite frequently overlooked, but contribute to the level of water vapour in the air.

Condensation causes problems so avoid it today

Condensation is mainly a ventilation problem. With a little thought, some good airflow, double-glazing and some insulation you can make a massive difference.  

For more information, on how to improve your windows this winter time, talk to our experts.

Condensation on windows


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