Our neighbours are relatively new, and recently converted their double story detached garage into an annexe. It sits directly opposite our bedroom and they have had a Velux window installed in there, which when opened, looks directly into our master bedroom (and vice versa, as it is their daughter’s bedroom). We can see all her furniture etc, just to try and give some perspective on what it is like. We have never had a problem with this, as we’re rarely in our bedroom during the day, and when the velux is closed, it is frosted.
However, our house is on the market, we have viewings and the window is wide open as it is warm here. Would we be unreasonable to ask them to close up the window just during the time we have viewings? We have a very polite relationship with them and would stop to chat with one another, if that makes a difference. The daughter is rarely at home, but happens to be presently and I would hate for a prospective buyer to be put off by what is a rare occurrence.
No, you should not ask them to shut the window - YABU
Yes, it is ok to ask them politely to shut the window during viewings - YANBU