The walls that I painted are in a house about 10 years old and had only been painted one time with a flat finish prior to me painting them. I noticed that the area within a couple feet of the ceiling (around the entire room) was very rough so I decided to sand it first with an orbital sander for a smoother finish. The sander had a dust collector but I still wiped down the entire walls before painting. I was going from flat to satin with Sherwin Williams Duration and was worried that all the roughness would show through with the satin finish. I painted the walls three times and have roller marks and an uneven blotchy finish around the top of the walls where I sanded. The paint seemed to dry quickly even on the 3rd coat. I plan to add flotrol (spelling?) to help with that if I repaint. What I am most concerned about is the blotchy uneven finish from sanding. I was told at the paint store that I didn’t need a primer if I was planning on painting two coats, but what if the roughness was from ceiling overspray that was oil-based? I am so frustrated! I expected sanding to make it better not worse! Should I prime and paint again? I just painted the three coats last week – only one coat per day. It was a lot of work for such terrible results! Where did I go wrong?
Before re-painting always sand all the walls.
Usually walls are painted in latex and doors in oil. Over the latex paint you don't need to prime. Just sand and put 2 coats of paint. We always use 2 coats of paint.
In case if walls was painted in OIL usually in a kitchen or bathroom and you want them to paint in latex, you must prime them w/ oil primer before putting coat of latex.