Ten minutes of open window costs less than heating damp air all day
Ventilate briefly
Windows wide for five to ten minutes twice a day rather than a small gap all day. The air exchanges without cooling the walls.
Cover pans and vent tumble driers
Cooking and drying produce several litres of water a day indoors. Lids and a vented drier remove most of it at source.
Move furniture off cold walls
Fifty millimetres of gap behind a wardrobe on an outside wall prevents the commonest mould patch in any house.
