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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?
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 https://www.backtoearth.co.uk/fix-sills-and-window-reveal-insulation/
Hope that helps.
We offer dynamic heat and moisture modelling as well as condensation risk analyses.
Back to Earth is a natural building material supplier. We're not your typical builders' merchant though and instead work closely with our clients during the planning, designing and building phases of projects.