Condensation and Replacement Windows
Will new windows solve an internal condensation issue?
Well, they might make it better or worse – explained in the following.
What is condensation?
It is where the water vapour (water held in the air) changes into liquid if the temperature of a surface is below the “dew point”. The dew point is determined by the amount of moisture in the air.
If there is more water in the air –condensation forms at higher temperatures. Lower surface temperature – more condensation.
Therefore you can either:
- Reduce the moisture in the air or
- Increase the temperature of the surface
Reducing moisture
Windows don’t produce moisture; they are a symptom of moisture in the air. Therefore, the most effective thing you can do is reduce the vapour in the air (from bathing, breathing, drying clothes cooking without lids on pans etc.)
You can do that by opening windows, doors, extractor fans, dehumidifying, air ventilation system or producing less moisture.
N.B. Old, drafty windows do provide some ventilation – a minus in the column for newly fitted (sealed) windows.
Increasing the temperature of the surface
Newer windows will likely be more efficient and therefore warmer on the inside. It will therefore improve the condensation issue – in favour of new windows. They will likely have trickle vents and secondary (partial) openings so allow you to control the situation.
Heating on – moisture out!
In my own home, when we changed the windows from older to newer more efficient double glazing the condensation reduced massively. I have also lived in listed buildings with large single glazed windows – and there was almost no way of stopping the condensation on them as they got so cold.
In summary – newer, more efficient windows could help, but they can’t put the lids on pans or open themselves!
Condensation on the outside of new windows – a note
Sometimes when new windows are installed, they form condensation on the outside pane.
What is happening there is that the old windows got warmer on the outside (leaking heat – less efficient). The temperature of the outside of the window is now lower, so condensation will be more likely to form. It shows the windows are working correctly. Heat the room to get the window warm (will help) – enjoy the fact that the new window is keeping more heat in!