Why do some skylights “perspire” and leak water into the home
Condensation on windows and skylights can be not only troublesome but cause damage to finishes and substructures. This problem can occur when it is cold outside and warm inside, especially with moist air. This problem occurs most often with aluminum framed skylights without thermal breaks and with single domed skylights. Best solution is to throw the old one away and replace it with a newer designed skylight such as the Velux FCM Model. One way you can stop the problem temporarily is to create air flow inside the room. Try turning on a ceiling fan, on low speed. Any kind of air movement can stop the problem. Keep in mind you still are having tremendous heat loss and so it is better to replace the skylight and save on your energy bills.