Fine grooves in level 4 drywall finish
Hi all,
We’ve just completed a Level 4 mudding job on our drywall, and I’ve noticed some fine grooves or sanding marks left behind in the surface (see attached photo). These appear to be from the final sanding — they’re not deep gouges, just subtle linear grooves that are visible under certain lighting angles.
I’m wondering:
• Are these kinds of sanding marks/grooves considered normal in a Level 4 finish?
• If these grooves are consistent across most surfaces, will a coat of primer and finish paint typically hide them, or should I go over everything again with a final light sanding before priming?
We’re aiming for a smooth, high-quality result but not expecting Level 5 (no skim coat planned). Just not sure where the bar typically is before moving to primer and paint. We’ll be using a matte mineral paint overtop.
Thanks in advance for your thoughts — really appreciate the help from this community.
PS. I also included a photo of the screw holes as I wasn’t sure if there was enough mud applied to these spots.
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That patch in the first pic should be more consistent in terms of finished texture to the surrounding area of wall surface. The second pic looks a bit scored to me, like something got stuck in the drywall kinfe during mudding, or a little clod of abrasive got into the sander. I'd try to fix that with a light sanding prior to priming.
Primer will fill some of the very fine scratches, but those deeper lines might telegraph through. The same goes for the patched area. You want a consistent texture when you're done, you don't want patches to show up as smooth spots.
Bill
Thanks, Bill. You’re right — those grooves in the mud are likely from the knife and just didn’t get fully sanded out during the final Level 4 sanding. I’ll go over them with a 220-grit sanding block and see if I can smooth them out myself. (I was just surprised to see those marks after the contractor had finished sanding.).
As for the patch over the screw hole, it might be tricky to get a consistent texture since the mud is smooth and the surrounding drywall paper has been sanded a bit rougher. The mismatch stands out slightly, like you said. I suppose a broader feathered patch over the screw holes would have blended better? I’ve attached a couple more photos of the walls for reference of how the screw holes are finished.
Yes, a larger area of patch usually helps hide things better because you can feather the edges more gradually over a larger area.
If you do have any issues with things showing through the primer, a cheap disposable foam brush used as a dabber and when used lightly with care, you can usually even out fine variations in texture until you can't see them anymore. Using high build primer helps too, and sometimes a second coat can also smooth things out. Ideally a level 4 finish is pretty much perfect, with zero variations across the surface of the wall. Normally you do this by skim coating the ENTIRE surface of the wall.
Bill
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Thanks, Bill — appreciate the help.
At this point, would you say it’s reasonable to ask the mudding contractor to come back and better feather out the screw holes? He won't be thrilled about it, but we did pay for a Level 4 finish, and I was under the impression that Level 4 would be pretty close to perfect (although I could be wrong!).
As an additional consideration, we’ll be using Keim matte mineral primer and paint — one coat of primer and two coats of paint. From what I understand, this type of paint may do a slightly better job of masking minor texture inconsistencies compared to conventional latex paint, so I’m hoping that helps a bit.
(Re: skim coating the entire wall, I understand that's only done for Level 5.)
A level 4 finish is just a regular drywall finish, nothing special. There will typically be a few areas that need extra attention.
Yes, sorry. Level 5 is the skim coat. Somehow I'd read that that's what you were trying to achieve.
I do find that a very wide putty knife, as in 8-10 inches or so, can do wonders for hiding stuff, even screw patches. It's like the goofy ads for the Pontiac Wide Track, if you remember those: "Wider is better" :-)
Bill
Thanks, Bill and Michael. Sounds like this is par for the course, then. Appreciate the quick comments.
Just for fun, adding a few more photos from the job. You can screen the tool etches in the close ups.
How close are you to the wall in the last two photos? The bubbles on the right look like drywall dust that has been painted over, but I assume all photos show the wall before paint?
Drywall primer is available with a filler in it that helps smooth out small flaws. If the flaws are limited to a small area, the painter usually fixes it. If the issue is extensive, it's reasonable to ask the drywall finisher to come back.
Hi Michael, that's right — all photos are pre-primer. I'm about a foot away from the wall and those bubbles are just a clump of dust that I can wipe off.
Those gouges look to me like little dry bits of drywall mud got stuck to the edge of the drywall knife during finishing. You need to wipe the edge clean periodically to avoid those. Those things always seem to haunt me around the end of the day, so that just as I get that perfect finish, I'll make one more pass and then.... #$!^#$^ marks from dry bits! Argh! :-D
I have sometimes found it helpful if there is a lot of issues to clean the wall, prime it, and then do a final patch and sand job before priming it again. The primer can help lock things in place a bit, which seems to help sometimes on problematic walls. This seems to especially be the case when using "dust control" mud, which is very easy to scratch and dent before being "sealed" with primer. Although the dust control feature is pretty nice from a dust control perspective, I no longer use the stuff because it's much less durable than the more common plus 3 stuff and hot mud.
Bill
Thanks, Bill.
As a next course of action, I'll start with priming a single room and see how it turns out in terms of covering the grooves and the overall finished texture of the wall.
For anyone else using Keim mineral point, I spoke with their product team and they recommended the same, just to test and wall and see. They said flashing is the big issues, and it's hard to avoid it unless you go to a Level 5 finish.
The rep also said not to sand either the primer or finish coats with mineral paint. Our plan was to patch any remaining nicks and dents after the primer with spackle, so that might be a challenge now if they are recommending not to sand this coat.
Anyhow, I'll test a wall and see!