I live in an apartment complex with a dedicated maintenance crew. I noticed that one of our bedrooms is a lot colder than the rest of the apartment, and of course when inspecting the sliding windows, I found that there is a noticeable air leak.
The leak is coming through the groove of the sliding window. I'm not sure I understand how air is coming through this groove, but it's very clearly a problem, as I can easily feel the air leaking in from outside.
I called maintenance, and the man they sent says that it's a problem that can't be fixed with weatherstripping, and the only solution is to replace the windows. Apparently they are aluminum windows and that's a common complaint they've been receiving. Instead, he offered to cover the window in the plastic insulation that you can get at any Home Depot or Lowe's.
Either way, it's no cost to me, but I find it hard to believe that this is just an accepted problem of aluminum windows. Is there really no solution to this problem other than replacing the windows?