The Mechanics of Condensation

Water exists in 3 states: solid (ice), liquid (water), and gas (water vapour).


Hydrogen Bonding

Water molecules in liquid form bonds which create a dense material.

In ice and liquid water, individual H2O molecules bond together in a special way, called ‘hydrogen bonding’.

In gas form, the kinetic energy of the molecules has overcome these hydrogen bonds, and so the individual water molecules are free to move. The water molecule itself is light compared with other gases in the atmosphere, so it tends to migrate upwards, ie, into the roof space.

Water vapour may condense into liquid form when the concentration rises or the temperature drops. The temperature at which air can hold no more water is called the 'Dew Point'. The water vapour capacity of air is relative to temperature.


Shower Condensation

The high humidity created while showering causes condensation on even relatively warm surfaces because of the high concentration of vapour.


Condensation on a Cold Surface

In warm conditions, condensation will form on a cold surface, even when the concentration of water vapour in the atmosphere is low.



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2 - Editing and rearrangement
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Clause revised and renamed, it is now: The Mechanics of Condesation.

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