Originally Posted by coffeesnob
I don't know about crappy windows. She upgraded just about everything in the home. But thanks all for your input.
I came up with 3 possibilities
First, 'upgraded' doesn't always mean they're good windows. I hate to say it, but there are a lot of builders these days that sell useless upgrades to people who don't know better. Someone mentioned she is in a quickly developing area, that means lots of housing built in a short amount of time, corners cut, costs cut to maximize profit, etc. I don't know the builder, and I hope it's not the case because they give good builders a bad name but poor quality windows could be the cuprit.
Second, even if they are good windows, if they weren't installed correctly, that could lead to condensation issues. Cold air gets around the frame and makes a cold spot on the inside, causing condensation. Ask her if she can feel a draft on her hand at the perimeter of the windows on a cold, windy day. On a calm day, she may not notice, when it's windy, you'll notice if they weren't installed correctly.
Lastly, since you said she did upgrade pretty much everything, the comment about the heating system having a humidifier that's set too high is definitely a possibility. In that case, you'd either need to turn the humidification system down or turn the heat up to help support the extra humidity.
Either way, the windows are a potential issue. They aren't thermally broken well enough to stop condensation. You can't have condensation if there isn't a localized temperature drop to cause it. That doesn't necessarily mean they're 'bad' windows, but they're certainly not top of the line.