LIMITING THE DEVELOPMENT OF AQUEOUS VAPOUR

• If possible, do not hang your laundry to dry inside the house.
• Close the doors of the rooms, in which you cook or take a shower.
• Reduce the number of pot plants.
• Ventilate regularly.
• Do not let the atmospheric humidity exceed 40%.
• Keep a constant room temperature of 21°C, if possible.

TREATING WATER STAINS ON THE FRAMES
All VELUX windows are pre-treated with fungi and rot preventing impregnation. In addition, all windows produced after May 1996 are factory-lacquered with a finish, which makes them humidity proof to a high degree. In spite of this, over a period, stains may appear caused by condensation. These discolourings do not actually harm the window and can easily be removed:

• Grind down the spots that have been discoloured.
• Lighten up the discolouring with a detergent containing chlorine.
• Apply an acrylic clear lacquer with fungicide or a water-based acrylic lacquer on the surfaces.

VENTILATING CORRECTLY

When condensation forms on the panes of your windows, consider it a warning signal, telling you that you should ventilate at once.
Correct ventilation is achieved by opening your windows completely 3 - 4 times a day for 5 minutes, at best, creating a draught. In this short period of time, you will ensure that neither furniture nor walls will cool down during ventilation. By doing it this way, you do not only replace the humid indoor air by the dry outdoor air - you also save heating costs. If the windows are open constantly, or the ventilation flap is never closed, this will cause unnecessary loss of energy in the heating season.
If your central heating system is provided with automatic thermostat lowering for the temperature during the night, you should ventilate before the heating temperature is lowered. In this way, you will avoid the warm room air condensing when it is cooled down during the night.
Ventilating correctly is the most efficient way of preventing condensation from forming on your panes.