Legal Issues

In the US, it is perfectly legal to go nude in your own home, even with the windows open.
It is illegal for someone outside to be looking in your windows.
The most the police will do is suggest you close your drapes.
At most, the person who called the police because they saw you naked through the window would be fined or arrested for being a peeping tom.

The answer depends entirely on where "here" is. There are several places in the US where you can legally go about your own house naked, or even sit naked on the front porch reading the evening paper while families walk past. There are other places that have more oppressive laws on nudity. Almost everywhere allows people to be naked in our own homes, but don't stand at night in a lighted window doing something explicitly sexual. Some countries like Spain have a rights constitution that allows general freedom of nudity. The UK is struggling with "The Naked Rambler" who gets arrested walking naked through town but the charges are dismissed. Some on-line resources have local information. Try The Naturist Society.

If you can't be seen from cars passing on the street or people walking by outside, then I'd say you're safe. My wife and I often do the vacuuming and mopping naked or just hang out naked in general. We have glass in both of our back doors, but we don't worry about someone waling up and seeing us. After all, it's not like we're mowing the front yard naked!

Laws vary so it depends on where you are