Does cavity wall insulation cause condensation on windows?
No it doesnt. It is not a good idea to insulate cavity walls – it blocks circulation of air in the cavity, and causes damp build-up. You should make sure that your home is well ventilated – you need to allow condensation to escape – the windows should be vented, fireplaces vented, and a few gaps around doors and windows won’t go amiss – air-flow is essential! Humans produce pints of water a day in sweat – it all has to go somewhere – and if you seal the house, the water builds up in the atmosphere and condenses where it is cold – ie, the bottom of walls, and cold windows.
