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Insulating thick walls with small windows


Our solid walls are 60cm thick and the windows quite small. We want to insulate internally but not to lose light, what happens if we just leave the interior of the window recesses uninsulated?

Topic starter Posted : 10/03/2021 2:16 pm
Chris Brookman
Member Admin

Hi Oli

Unfortunately if you leave the window reveals uninsulated you will tend to get condensation and mould growth on them. As you insulate the rest of the room you raise the temperature and the absolute humidity of the air which means that cold surfaces are actually more likely to suffer with condensation.

Our suggestion in window reveals is always to use the 20mm UdiDiffutherm reveal boards to avoid this type of issue. You can see more about how to install them here

Hope that helps.

Posted : 10/03/2021 2:41 pm

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