Finally figured out the difference between plastering and skim coating for my renovation

I went thru the exact same thing when we were doing the nursery and hallway last year. My guy tried to tell me that the "plastering" in the bid only meant patching the holes where the old electrical was pulled through, not actually smoothing the surface. He wanted an extra $8,000 for a "Level 5" finish on about 1,200 square feet of wall space. I almost fell for the moisture absorption line too, but luckily my brother-in-law is a drywaller and told me to just use a high-quality primer like Zinsser Gardz to seal the old plaster first. The terminology is definately where they get you. If the contract says "paint-ready," that shold include whatever skim coating or sanding is needed to make it look decent under a light. I ended up buying the USG Plus 3 blue lid buckets myself and told him I’d find someone else if he didn't honor the original scope. It's wild how much the prices vary once they think you don't know the difference between a brown coat and a finish coat. Taking that second opinion was the smartest move you coud have made.

My experience was actualy the opposite. When we did our 1920s Victorian, the plaster was crumbling behind the old wallpaper. The contractor quoted me for "basic repair," but once the walls were bare, it was clear that just patching wouldn't work. I actually insisted on the Level 5 finish becasue I was using a high-gloss Farrow & Ball paint in the dining room. If the walls aren't perfectly flat, that expensive paint shows every single ripple and bump. Instead of paying the $15,000 surcharge they wanted for the hand-applied skim, I met them halfway. I had them do a standard Level 4 and then I went in with a high-build primer-surfacer like Tuff-Hide using a rented airless sprayer. It filled the minor imperfections without the labor-intensive sanding of a manual skim coat.

It’s often less about being screwed over and more about the finish you’re actually expecting. If you're using a flat matte Benjamin Moore Regal Select, you can get away with alot. But for anything with a sheen, that extra prep isn't just fluff—it's the difference between a professional look and a wavy mess. Just make sure the contract specifies the GA-214 levels of finish from the start so there's no room for "misinterpretation" later.

Whoa, reading this is such a lifesaver! I'm just starting to look into all this beacuse I finally joined the forum to learn about custom woodwork. It's crazy how much the prices jump around. Since you mentioned the skim coating for the walls, does that ussually affect how the door frames sit? I’m looking at these gorgeous solid oak interior doors and I'm terrified the contractor is gonna charge me extra to 'shim' them or somthing if the plaster is too thick. Anyone know if doors get weirdly expensive when you change the wall finish?

Spot on about those hidden costs. People really don't realize how much these guys lean on those confusing finish levels to hike up the bill. One thing you've gotta watch out for when you're pushing back on that skim coat is the thickness around your door jambs. If they skip the proper feathering to save on labor, you'll end up with a noticeable 'lip' where the wall meets the casing. It makes even the most expensive solid doors look like a DIY hack job becuase the trim won't sit flush against the plaster.

Ugh, the old 'moisture absorption' line is such a classic. If you've alredy got those solid oak doors picked out, make sure they aren't using the wall prep as an excuse to mess with your hinges later. I've seen guys try to charge extra for 'custom shimming' just beacuse they didn't level the plaster right around the rough opening. If the wall's too thick from a lazy skim job, your casing's gonna look wonky and they'll try to bill you for the fix. Don't let 'em double-dip on the labor.