When we moved into our house four years ago there was a patch on the south side of our bedroom wall that was bubbled. We were told it was because the paint has nothing to cling to. We chipped the old stuff away, sanded and spackled and repainted. Now the paint is bubbling next to where we had done our work. This area is under a window, which we had replaced about 2 years ago. It's also the window where there is a portable air conditioner unit (We didn't put the air conditioner in last year because there was only three days it was worth having).
I have a few questions for anyone who can help: 1. Why is the paint bubbling? Is it left over moisture from the old non-energy efficient windows? 2. If I chip all this paint and respackle like before, will it go away? Right now it looks like there are some hairline cracks a pretty good distance from the area.
Seeing as how you are going to have to patch the area anyways, you might want to cut a hole in the wall and see what is going on. My best guess would be water is leaking into the wall from the window and poping the paint. If you are getting water in the wall then the hole you cut will air it out and help further bubbling.
Nope.. moisture in the wall is putting pressure on the paint film. Nothing else will cause this. The drywall needs to be removed, water leak resolved, wall cavity allowed to dry and insulation replaced.