The windows are old old old single-pane things, one of them doesn't close completely, and they leak air like a sieve. They have honeycomb blinds installed, and those help, but I think I want to put drapes over them as well to help keep the place warm.
The problem? The ceiling and walls are both 80-year-old concrete, and I'm not sure what the easiest/best way is too mount curtain rods. Ideally I'd like something that could be done without drilling, but I have no idea if there are any adhesives that might work. I'm fairly flexible on what kind of rod, and I don't care if it's fastened to the wall, the side posts, or the ceiling.