The walls and ceiling have alot of layers of semi-gloss latex paint, on top of that was wallpaper. I've stripped the wallpaper and found lots of nail holes, chips, flaking paint, etc. After I've fixed the damage, I want to use an oil-based primer and oil-based paint. Since the walls have semi-gloss paint on them, would I have to sand them to roughen them up for the new primer and paint? The bathroom is not large and I have a palm sander, so it shouldn't take too much time. I just want to make sure I'm properly preparing the surface so I won't have to repair it a year from now.
Thanks for any advice you have =)