hi jason, the windows where installed by a contractor. double pain low "e", argon gas filled. i watched most of the work and the guys did a pretty good job, especially with the insolation around the windows, they don't leak. the average temp. is aorund 30 degrees or lower outside and 68,70 inside. if it gets to 40 or above outside the moisture starts to disappear. no heavy curtains around. we have force air heat, gas. the attic vents are working but maybe i'll install some more sofett vents? its not justthe bathroom, its the bedroom also, which just happens to be connected to the bathroom. i do have aq cement floor inthe basement and a sump pump. very little water is ever seen in the well area. maybe i will take the dehumidifer upstairs and see what that does???? any more suggestions. thanks for all your help jason i really appreciate it.