Lots of ladybugs in the house today, and I read that they're getting in through the windows, so I went to inspect. One window in particular has a large gap at the bottom. All of the windows on my house are not caulked in that spot, although some have almost no gap.
Bottom of window (that's a metal sill on the bottom):
Closeup:
I also noticed that all windows have a gap at the top as well (also, what about the vertical gap the orange arrow is pointing to?):
It's really weird to me but since ALL the windows are missing caulk in those spots, I'm thinking maybe there was a reason they weren't caulked? Should I leave them alone? I am not very well-versed in windows, so forgive my terminology (if anyone can point out to good resources, would be appreciated)
Best Answer
In these photos, it looks as through there is a foam backing strip -- this was probably put in to form a seal a long time ago, when the gap was smaller. If this is the case, you might want to get another foam strip and put it in the gap to seal it.
Also in the second picture, it looks like there is an old caulk joint at the bottom of the image, which has cracked over time.
It's possible that these gaps get larger and smaller over the course of seasons, but I don't think that caulking them on the edges would build up enough force to mess anything up. My guess for why they're there at all is that the components were aligned flush when the house was constructed, and there was no need to caulk them.
The major downside I'd expect is that removing those window frames might be slightly more of a pain if you ever decide to have them replaced.
The answers on a previous question regarding this subject mentioned a couple things about trapping water in, so this might be a good point to start off for more research:
Should Caulk be used around vinyl windows