Friends, I bought I house and I need to apply a new paint on some drywalls. I’m wondering if sanding the previous paint is “mandatory”or is it possible to get a clean result if I keep the previous paint beneath the new one please? All the professional websites say that it’s mandatory but all my friends tend to say that it’s not. What’s your experience with this /diy/ ?Also, what kind of sander would you recommend please? Is a manual sander enough or is a big electric one necessary? I understand that sanding would be only to create imperfections on the wall for the paint to stick, not to fully remove the previous paint so I understand that only superficial sanding is necessary but I’m uncertain my understanding is correct.Thanks
>>2866500I would say a good sanding smooths out some of the uneven texture and then a high quality primer applied 1-2 coats will take care of any bleed-through. There are even special primers that mimic a level 5 finish to some extent (that's smooth skim-coated drywall). Your primer choice is key in painting over existing paint on drywall. It's very likely that after sanding and inspection under strong lighting, you'll see many imperfections that you'd want to patch up or skim coat over though, so get ready to do some serious drywall finishing.
