We have recently visited a property where there is little ventilation in the bathroom and consequently a mould problem has developed. Our solution to reduce moisture levels was to install a motor based air vent system.
The motor is permanently connected to the main supply and on this occasion will be fixed into the loft. There is a choice of 2 speeds high or low. The motor in the picture runs permanently at a maximum of 36db [this varies on model type] and is quite unobtrusive. The vents are fitted in the ceiling of the bathroom, toilet, kitchen and/or any other room where ventilation is required. The conduit souple or flexible hose connects to these vents and then to the main motor.
If you want help or advice in reducing your moisture levels ... vent in our direction.