I have some windows that I want to insulate at night during the winter. I have energy star windows, thermal drapes, and cellular blinds and those plastic window film kit things, but I want to reduce my heating costs even more.
From my quick googling it looks like there is some danger in insulating "too well" from the inside, namely that I could end up with the window getting too cold and getting damaged by water or other thermal stuff. If that's wrong, please let me know and ignore the rest of this question.
If that's right, then I'm wondering what I can do to insulate my windows further while avoiding this issue. To me it seems intuitive to try and insulate my windows from the outside, ideally in a way that I can "turn off" during the daytime. Any ideas of how to do this? Maybe some kind of fancy shutters?