Windows

Double glazing reduces air movement. However, we need to retain some of that air move for ventilation.

Single glazed windows act like dehumidifiers, reducing the vapour in the air. However, sometimes this causes damp to run down and moisten walls and timber, often causing window rot.

Surveyor tip

1. If you have trickle vents, they should be kept open and cleaned periodically to remove debris.
2. If you don’t have trickle vents, then opening windows on a safety lock works as well.
3. In countries like German, it is common to purge the whole house, i.e. have all the windows open for about 30 minutes, every day in the morning.