A savvy mum has revealed a simple way to stop condensation on your windows for just 65p - by using salt. Nazia Safa discovered that leaving a bowl of salt on the window sill overnight stops moisture seeping through the glass. The mum-of-three had originally tried using washing up liquid on her windows but found the water from the product ended up on her window sill. But she found salt does the trick, and a bottle costs just 65p from most supermarkets.