Why condensation forms on windows and doors

Knowing why the condensation forms on glazing can help solve the problem quickly without too much expense . Each area of condensation is caused by something different :

Inner condensation is caused by an overabundance of water vapour in the air inside a home . When the outside of the window gets cold , the warm , damp air hitting the window on the inside will turn into condensation . Householders are likely to notice this happening more when they are cooking or showering , as well as during the autumn and winter , when the inside of a house is warmer than outside .

This type of condensation is very common on single-glazed panels and can easily form on more efficient double-glazed windows and doors too . People are surprised at the amount of water vapour that a household generates in a 24-hour period . Showering , drying clothes and cooking are all obvious sources of inner condensation , but people also create water vapour by simply breathing and going about their day .

Approximately 15.7 litres of water vapour are produced a day by the average four-person household . Without the proper ventilation , this can cause condensation and damp problems .

Outer condensation is caused by the same reaction , just the other way around . It affects properties which have very efficient windows and doors , and is caused by warmer air hitting the outside of a window . This is most likely to happen in the morning , as the sun is coming up and could happen in any season , depending on the conditions . This does not mean that the inside of the home is cold in comparison — it simply means that the glazing is so efficient that the outer pane is much colder than the inner one , hence the condensing reaction with the air outside .

Gap condensation happens because of the double-glazed unit failing . All double-glazed windows and doors have a small gap between the two panes . This space is filled with a harmless gas , which creates an insulating layer of air , thus helping to keep the warm air in and the cold air out . If the seal has broken around the edges of the unit , the insulating gas will escape and condensation will occur between the panes . This can , in some very extreme cases , cause the inner space to fill with water .

Related issues

Both inside and gap condensation cause problems and should be addressed as soon as possible to prevent further issues and expense .

Gap condensation within double-glazed units seriously reduces the energy efficiency and will have a noticeable effect on the temperature in a household , not to mention energy bills . If there is more than one failed unit , heating bills are likely to be higher and there are more issues with damp and condensation on the inside of the window , due to the decrease in energy efficiency .

Inside condensation can cause damp or mould in the worst affected rooms . This usually manifests as green or white patches with discolouration of paintwork and / or peeling wallpaper , usually in the upper corners of the affected room . Residents may also be able to smell the damp as it can emit a rather musty odour .

If they commonly find condensation on the inside of their windows and doors , it ’ s