Scrape whatever is loose and then use Gardz. Odor is strong for a bit if you do all four walls, but way easier than oil cleanup.It a snag in the today painting a garage the cut in went fine and then I started rolling the walls . The old paint started flaking offand you can tell by the pics that the sheet rock wasn't primed . Ya think I shoul oil prime or guardz . Thanks in advance View attachment 111210 View attachment 111210 View attachment 111211 View attachment 111211