A. Drywall contractor Myron Ferguson responds: Something similar happened to me in the past. I taped a house to a Level 4 finish, which should have been good enough because the rooms were relatively small. The homeowner then hired a friend who had an airless paint sprayer to spray on the primer. He applied a thin coat that left the surface a little rough, especially where the paper was roughed from sanding. This is perfectly common when spraying on primer. It's easily corrected by sanding with a fine-grit paper before the finish paint is applied; or it can be prevented by backrolling as the paint is sprayed.
In this case, neither action was taken, and a low-sheen finish paint was applied. The rough areas were visible and I was blamed for doing a poor sanding job. And in fact, if I had given specific advice on painting before I left the job, I would have saved everybody a lot of trouble.
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