I recently had my home built in a rural area (very open to the wind). During winter months (this is the 2nd winter in the home) most of my windows will get a little moisture on the glass, just above where I lock/unlock the windows to open. My problem is the 3 windows on the Northwest side of my home actually get enough moisture to run down the window and onto the window sill. I have put 3m film up, but still get some moisture onto the film before going down on the window sill. I have my contactors coming over to look at it, but I am wondering about how to go troubleshoot this problem before they arrive. I don't understand too much of the lingo, but would do my best to answer any other questions to try and help resolve this issue.:)

p.s. I did feel around for any type of air leaks, but really couldn't find any significant ones.

Tell us about the type of window you had installed when you built. Are they thermopane, low E or what? Where do you live?

Low E in rural Wisconsin town. I did put a hygrometer in the rooms and in the morning hours it's showing a humidity of 65%. I do have a dehumidifier, but don't really want to just run it in each of the two bedrooms. Is there an easier way to lower humidity?

What kind of furnace or heat do you have. In your climate the inside air should be pretty dry this time of the year since your temps have been in the 20s at night. Exhaust fans are needed in newer home for cooking and showering, could this be your source of the humidity?

It's a Rheem furnace run on LP. We've got exhaust fans throughout the house. One thing my wife and I just realized too is we had our blinds all the way down. Since we've pulled them up, air has been able to move in front of the windows eliminating just about all the moisture.

Circulation does help but you still have higher than normal humidity. I set my stat to FAN ON rather than FAN AUTo, this keeps the temps more even, lowers humidity and catually costa only pennies more than running the fan periodically.