All posts tagged: skim coating

How to Skim Coat Walls with the Best of Them.

Here’s how to skim coat walls with the best of them: hire the best of them? OMG YOU GUYS I FIGURED IT OUT! Are you inspired yet?

I’m the worst.

But here’s the deal: renovating a house involved a LOT of different technical skills, and you don’t have to walk into it with any of them, really. I didn’t! And while I think it’s good to dip your toe into all sorts of things to learn how they work and whether you actually like them, after you’ve done that I think it’s OK to be honest about what you find enjoyable/gratifying and cut yourself some slack on what you don’t. For me, I’ve found that I really enjoy some woodworking/carpentry times, basic electrical, tedious crazy tasks that wouldn’t really make financial sense to hire out (removing and planing down all the original clapboard on my house, for instance!), and plenty of other things like painting and restoring windows that’s neither fun nor un-fun but manageable and fine and kind of satisfying. And then there are other things that I have very little interest in, like plumbing and, you guessed it, skim coating. I love a restored plaster wall. I don’t want to restore all my plaster walls single-handedly. I like parts of it (stripping down the plaster, installing plaster washers), but the actual skim-coating part I’m thrilled to hand over to a pro when I can. I can do it. I don’t want to do it. So for the den-ovation (thanks to Jaime for that delightful word combo that I will shamelessly co-opt), I hired my main man Edwin to take on the bulk of it. Lucky for you this freed up my hands to take some process pics which we will now review. Let’s learn from the best in the hopes that we might someday be the best? Or just be OK with not being the best. Up to you.

THIS GUY. I love him with all my heart. He’s straight, just to clear anything up there. Edwin is my next door neighbor who I hired three years ago to install/mud/tape drywall on my first floor ceilings, and we’ve done a ton of stuff together since. It’s the most significant bromantic relationship of my life. I learn a lot from him and, believe it or not, he learns a lot from me. Life isn’t all sunshine and rainbows, but when Edwin and I work together it kind of is. Except that time I dropped a level on his head. Sorry Papi!

Also, what a stud. He likes to inform me multiple times a day that “in my country, they call me El Pollo.” Of course they do.

SO. Let’s talk skim-coating. I should preface all of this by saying that we’re talking specifically about skim-coating with joint compound, which is a bit more DIY-friendly for someone who’s not used to doing it, but IDEALLY we’d be talking about a plaster veneer. Plaster veneer falls into two camps from what I understand: hydrated lime and gypsum-based. Gypsum based plaster veneers are generally available at big boxes and the like, and are generally what people are talking about when they talk about plaster veneer in the United States. It sets VERY fast, dries VERY hard, and is super beautiful (especially when tinted and left unpainted!), but traditional plasterers typically apprentice literally for YEARS before they’re allowed to start “putting up” plaster on their own. It takes a lot of skill just to get the plaster from hawk to trowel to wall, and a lot of built-up muscle memory to get the application just right.

Hydrated lime plasters are WAY cool, and what I’d like to try next. It’s one of the oldest building materials known to man and remains one of the healthiest to live and work with. It has the ability to handle big swings in humidity and temperature, which is good in old houses that undergo these swings due to a lack of central air and modern ventilation and stuff. Lime plaster is essentially extremely finely ground limestone that’s fired at a temperature of about 1500 degrees to remove any impurities, and then some other stuff is done to it that I don’t pretend to understand, and then it arrives to you pre-mixed in a 5-gallon bucket. Whereas gypsum-based products have a shelf life because the wet varieties dry out and the powdered varieties take on moisture from the air and harden, hydrated lime is actually aged after packaging to achieve superior results. Once the hydrated lime is applied to interior surfaces, it takes CO2 from the air to “cure”—essentially completing the lime cycle and returning to a stone-like state on your walls! How cool is that? Application technique dictates whether your walls are kinda rough and uneven or perfectly smooth and shiny, which is just personal preference. Instead of sanding like with joint compound, you keep working the plaster as it’s curing to smooth out it out to your heart’s content. Cure/working time is similar to the dry time with all purpose joint compound, meaning it’s typically a three-coat process spread out over three separate days, and like gypsum plaster veneer it can be left painted or unpainted depending on taste. Also it dries to a PH of 12, making it naturally mold and mildew proof. This is why you can wet the shit out of an old plaster wall to remove wallpaper and stuff, and the wall is totally fine.

So those are some things I know—huge thank you to the folks at Master of Plaster for teaching me. They sell gorgeous restoration plasters which can be colored to your preference, and I’m so excited to try it out someday soon.

We didn’t do that though. I have zero doubt that Edwin has the skills to pick up plastering quickly from all his years of joint compound work, so we’re gonna learn it together. Then he can start charging an arm and a leg to do real plaster restoration work, so it’s a win-win! As long as he doesn’t try to hit me with those new rates, haha.

SO. I digress. We are talking about joint compound, the inferior but totally fine/normal way to do this.

Once the plaster is stripped down, plaster buttons installed, and cracks scraped out, the next step is applying fiberglass mesh to the cracks. You CAN do the window screening we discussed in the last post over the entire wall (particularly if there’s significant cracking), but mostly the walls in this room were in good shape so we used standard mesh tape just where it was needed.

I do NOT like paper tape. I feel like it doesn’t hold up, particularly on plaster. I don’t trust it.

We always end up using some combo of joint compounds for skim-coating, which is something you mainly just need to get a feel for. The All Purpose pre-mixed joint compound 5-gal bucket is fine, but the dry time is quite long (sometimes more than 24 hours, depending on temperature and humidity levels), and I don’t think it dries to the same hardness as some of the powdered alternatives. When I’m doing it myself, I tend to go for Easy Sand with a 90 minute set time, which for me is enough working time (now, not when I first tried this!), dries harder, and—as the name implies—does sand easily. Because Edwin has better technique than I do, for this we primarily used Durabondalso a joint compound but dries really hard, making it probably a poor choice if you rely on a lot of sanding like I do when doing this myself.

It takes some practice to get a sense of the right powder-to-water ratio, but you can always add a little more water after mixing. We tend to mix maybe a third of the bag at once. You’re going for a thick peanut butter type texture.

There aren’t really right and wrong ways to get it up onto the wall. I’m now OK with a hawk and trowel, but I started with a mudding pan that felt more manageable. You’ll notice that Edwin has a rounded trowel in his right hand (typically used more for plaster than joint compound) and a straight 8 or 10 inch taping knife in the other. He was excited to try the rounded trowel but he’s used to the taping knives. The benefit of the trowel is that the rounded edges make it easier to not leave lines, but personally I find the trowel difficult to get the hang of. Also of note—those dark patches are fiberglass window screening that we used over the upper section of wall where the plaster was more iffy.

Essentially you want to load up your trowel or knife, start at the top and smooth it all down (or bottom up, or side to side—whatever the hell makes you happy)—you’re looking for about 1/8″ in coverage or a bit less. Thin! But also thick enough! The key is to apply the right amount of sturdy, even pressure to the knife or trowel to get a smooth, solid skim rather than one with bubbles and other weirdness.

I find this difficult. The Magic Trowel makes this less difficult, but you don’t want to really rely on it—you still have to get a FAIRLY smooth and even coverage with the knife/trowel, because the Magic Trowel is really good for smoothing and filling in tracks left by the knife or air bubbles, that kind of thing, but not for actually getting joint compound up onto the wall.

Obviously, the wall on the left has a coat of compound on it, wall on the right does not. There are knives for finishing both inside and outside wall corners, but Edwin prefers to run a straight taping knife along one side of the corner, wait for that side to dry, and then proceed with the adjoining wall and its side of the corner. Trying to do both at once with this method will lead to some very messy corners.

See how there’s some yellow peeking through the grey joint compound to the left of the door? That’s kinda what you’re going for with a first coat in terms of thickness. I won’t pretend it’s easy.

After the first coat is up and fully dried, go around with your taping knife or spackle knife and knock off any high spots or weird globs. You don’t need to sand at this stage but you do need to get your surface even for the next coat.

Ugh, melt my heart!! Look at him go. This is the second coat going up. The second coat is when things really start feeling covered, much like with paint.

We all know by now that I am kind of a crazy person (if you’re new here, consider this your warning), so even though it’s totally abnormal, I think skim-coating drywall is something worth considering if you’re in an old house and trying to match up plaster surfaces to drywall ones. It’s NOT about adding weird texture or giving the walls some faux-rustic treatment, just about NOT getting those perrrrrrfectllyyyy flat walls that drywall is really designed for. I think this will also lessen the likelihood of the drywall cracking along the seams or screw heads popping over time, which I see with most drywall jobs after a few years. If you can tell where the joints are, it’s not going to look like a plaster wall.

Will anyone EVER notice this? No. It’s a normal wall that looks like a normal wall. That’s the point. But I will know it was treated the same way as its plaster counterparts in the same room, and I will appreciate it.

Same for the ceiling. You’ll notice for both that we mudded and taped as usual for the first coat, and then proceeded to a full skim for the second. It made my heart go all pitter-patter. Skim-coating a ceiling is my personal version of hell, but Edwin was undaunted. Told ya. He’s good at these things so they don’t seem like a big deal at all. Just another surface.

Look at that! The man’s an artist! I do NOT achieve these results pre-sanding. Or even post-sanding. That is why it’s worth it to me to hire out. It’s faster and easier but it’s also BETTER long-term than what I can do. My work is sufficient. His work is excellent. It’s not like this is the kind of thing you ever want to redo.

I’ve increased the contrast on this picture a bunch so you can see that up close, it’s not perfect. Not yet! This is after the second coat, and there are some track lines from the trowels and knives and unevenness. As with the first coat, you want to knock down any high spots and lumps after drying, and depending on how things are looking you might want to do some sanding. With Edwin we can mostly skip the sanding and just save it for the end. I have to sand when I’m going it alone.

Your final finish coat is primarily to fill in any of that weirdness, and Edwin likes to mix a soupy batch (think pancake batter!) and paint it onto the wall with a roller. It’s nice to have two people at this stage—one to mix and roll and the other to smooth.

Once it’s rolled, you work quickly to smooth it down—taking most of it off the wall as you go. Just enough to fill in pesky spots.

I might need to do this final coat a few times over as I continue to spot imperfections, but a more skilled skim coater can do it in one shot.

After that’s all totally dry, you can move on to the sanding! Confession time: right after I bought this house and was operating under the delusion that I’d be doing all the skim coating work myself, I bought myself this super expensive drywall sander that primarily just takes up room in my basement. It’s designed to hook into a running ShopVac to suck most of the dust, but honestly I find it difficult to control and I don’t like using it myself. Edwin is a big fan, though, and I often let him borrow it for jobs he’s doing. When sanding, even on a bright day, it’s good to shine a work light at an angle on the wall you’re working on—it just helps you see whatever needs to be sanded down.

This doesn’t get you entirely out of hand-sanding, though—you need to go back in with a sanding block around moldings and in corners and areas that are missed by first pass. After a first coat of paint, these seams where the wall meets molding get caulked.

The final step for me is typically knocking down the globs that like to accumulate on top of door casings and baseboards. You can’t see the top of the door casings if you’re just in the room, but I like knowing that these spots didn’t just get painted over because someone (who is me) was lazy.

So there it is, skim coating with Edwin! At this point, the room is pretty much ready to paint! Now I can get in there and tackle the moldings, CLEAN, and get some paint on these walls!

Prepping the Walls in the Upstairs Office!

I’ve been so excited to get it together and finish the little office room upstairs. I talked about some of the early progress back in the middle of November, and then shared my big exciting plan for the space, and I really wanted to have it done by Christmas (HAHAHAHA). And then things happened, like the holidays and the new year and tearing out a ceiling and then another ceiling and closets and…I don’t know. Life. The little office room more or less sat there, leading me to feel like a sad failure.

before

As you might recall, the walls of this room were riddled with pretty much every problem plaster can have. What looked like a fairly regular white room was actually layers and layers of paint on top of the original wallpaper on top of the original plaster walls. Unfortunately, over the years, the adhesives in the original wallpaper (and probably the wallpaper itself) began to break down, leading to lots and lots of cracks and flaking. In order to really restore the walls and prevent this problem from recurring over and over again forever, I decided that the best course of action was to strip ALL of the old wallpaper/paint off the plaster.

There were other major problems, too: all of the corners of the room had been repaired with a crazy (and very bumpy) layering of masking tape, joint compound, caulk, and paint. Same with the cracks, areas of missing plaster, and places where the plaster had come away from the lath but was still present. All of this was problematic because:

1) I want an office with solid walls that are not falling apart and looking a mess and made mostly of masking tape.

2) I plan to wallpaper the main wall of the room, and wallpaper really needs to adhere to smooth walls. None of this bumpy flaking crazy business.

plasterduring

It’s long been common knowledge that once plaster comes away from the lath (you can tell by pushing on it…a solid plaster wall will be, well, pretty solid, while a damaged one will give under pressure), the only thing to really do is tear it all down and replace it with drywall. Not so! Even plaster that looks pretty damaged and messed up can be revived with lots of plaster buttons and TLC. Plaster buttons are those little metal disks. They have a hole in the center, so all you do is insert a drywall screw into the hole and screw it in to either a framing member or lath underneath to pull the plaster back into position. I’m still getting my buttoning technique down, but that’s the basic principle. They’re great for ceiling repair but effective for walls as well.

This main wall of the office (the one that I’m planning to wallpaper!) was a disaster! Huge cracks, crumbly parts, missing parts…yikes. The first step was to scrape out any areas of plaster that were truly beyond saving, then implement the plaster buttons, and then patch missing areas with drywall. I used 1/2″ drywall—it’s best to just find the thickness that’s closest to your plaster. This might vary pretty significantly by the room, or even the area of the wall that you’re patching.

After this stuff is done, it’s time to start filling the voids and taping and patching the cracks and seams. Then the skim coating! Skim coating is the process of coating the wall in a thin layer of joint compound (or actual plaster, if you’re fancy/skilled/are applying it to bare plaster). It’s typically done over the course of 3-5 thin coats, depending on how much texture your wall has.

plasterbefore

The reason that the skim coat is pretty necessary is not only to smooth out areas of major damage, but also to create a smooth surface on areas that aren’t really damaged. I tried to take a close-up to show the actual texture of the walls before the skim coat. This is what all the walls in the hallway/entryway look like post-wallpaper-stripping, too. Just lots and lots of small areas of pitting and damage to the outer plaster coating, which will NOT look good if just painted over. You really need to smooth that stuff out for your walls to look like…walls.

Now, I was pretty pumped to be great at skim coating. I read over the Plaster Repair Series over at Old Town Home (Alex is such a wealth of knowledge and detail if you’re renovating an old house) probably 25 times to make sure I really understood the process. It didn’t seem that hard, and besides, people on the Internet tell me sometimes that I’m really handy (not really true at all, but I’ll take it). I bought all my tools and supplies and I was feeling pretty confident and amazing about the likelihood that I was a plaster repair prodigy and the whole thing would be a cakewalk and I’d have smooth, beautiful walls in a couple of days.

NOPE. NOPE NOPE NOPE. I have no idea which part of skim coating was so incredibly hard for me to grasp, but I could not do it. Seriously. I made one attempt, felt like I destroyed one wall, and had to walk away for a few days just to recover. Then I made a second attempt on a different wall and felt like I had destroyed that one, too, and I couldn’t even walk back into the room the next day to survey the damage. I think there was a third attempt in there, too. I just could not. 

I think this is why I started demoing so many things. Destroying stuff made me feel like I was still in control and capable of making forward progress. Skim coating made me feel like I was completely inept and my chances of fixing this house were hopeless (seeing as I have to do this in…pretty much every room?). Things were not going well. At all. Like really badly.

I think it had to do with the consistency of the joint compound, or something. You want it to be fairly watery and loose, but actually getting it from the bucket to a trowel and onto the wall and making it smooth is a whole different story. In high school I took Physics and received a B- in the class, so this kind of thing has never really gone well for me. Gravity. Friction. Mass. Slipperiness. Science.

The point is this: I was pretty stoked to rehash my skim-coating experience and break down my technique and be awesome. That will not happen because my skim-coating experience was basically just a lot of chaos and confusion and incompetence and emotional distress. BUT! I think I figured out a general technique by the end that worked for me, so I’ll be really detailed next time, when I’m not so frantic that I don’t really take any pictures because I’m too busy panicking.

mesh

Here is that same wall that was a disaster before. I borrowed Alex’s technique of using fiberglass mesh window screening material to do large-scale patching over areas that were really damaged and cracked, which worked out great! Since plaster will continue to move and crack over time, the idea is that the fiberglass screen isolates the top layer from the movement of the wall underneath, helping to maintain a crack-free surface. This is just after the screen was embedded in the joint compound (I used another screen on this wall, too, but didn’t take a picture apparently), but after a couple more layers of skim coat it’s completely embedded in the wall. You’d never know it was there!

deskwall

CHECK IT OUT. Does that look like a smooth wall to you? It looks like a smooth wall to me! With crisp beautiful corners and no crazy cracks or visible patches or anything. Totally ready for priming and wallpaper!

skimcoat1

The rest of the walls, like this one, will just be primed and painted, but that part seems comparatively easy and silly. Like being allowed to play with crayons for a while after having to read War and Peace in one sitting without blinking.

Also, take note of the new electrical! I said that I planned to have a ceiling fixture installed in this room, and now there is one! And a new plug! And a switch! It’s so modern you guys. Right now the ceiling light is just a temporary light, but I plan to buy a ceiling medallion and a real light soon (MEDALLION INDECISION ALL OVER AGAIN). I think I want to see more of the room come together before making a final decision on hanging vs. flush-mount for the light. It’s a very small space and the wallpaper is pretty bold and I’m worried that a hanging fixture will just be too much going on.

beforeandprogress

Ahhhhh. It looks so…real? Like being beautiful is realistic and within reach?

The one thing I’m already feeling a lot of regret about is leaving the tiny little crown molding in place. The ceiling of this room is actually drywall over acoustic tiles over furring strips over the original plaster ceiling (I know, I know, but it looks fine and there’s no real reason to take it all down), so the “crown” was put in place to create an easy transition between the plaster walls and the drywall ceiling. I was so overwhelmed with everything else during this skim-coating adventure that I opted to just keep it, and now I feel like the walls look so good that I want it gone. It’s just so dinky and damaged and it’s not even the same molding all the way around the room. But I also REALLY don’t want to spend several more days patching and taping and sanding and patching some more, and I feel like for this tiny room, I should just let it go, but…argh. I should have taken it down to begin with.

Maybe I’ll gather the strength. Maybe I won’t. Maybe I’ll just put up new, better crown, but that sounds hard too. And maybe expensive. And maybe like something that might not look great. But could it look worse? Maybe it could. It probably could. But it also could look better.

This is the type of thing that keeps me up at night.

chimneydetail

I feel really proud of my corners. All the interior corners were restored with joint compound and fiberglass mesh tape, and the exterior corners were repaired with new corner beads. These corners are a little wonky (it’s plaster over a brick chimney, and there was a lot of damage and weirdness), so I chose to use vinyl corner beads instead of the more conventional metal ones, since they seemed more flexible. I have no clue if this was a good idea, but it happened and it looks OK right now?

So this is what I learned, I think:

1. For corners and small cracks, you want to use fiberglass mesh tape. Do NOT use paper tape to patch plaster. For large scale patches, fiberglass mesh screens are effective and WAY cheaper than large fiberglass screens made for this kind of thing. It’s very hard to work with sections of screen larger than about 4’x4′, so cut and plan accordingly.

2. Give yourself options with the joint compound. I used a mix of pre-mixed joint compound and lightweight setting-type joint compound (90 minute setting time) that you mix yourself from a powder. The powder kind is more cost-effective, but I found it helpful to have the pre-mixed on hand for various things. Somehow I used up almost an entire 65-pound tub, along with a few bags of the powder kind.

3. Experiment with tools. I honestly just could not get my hands and arms to do the things necessary to handle a hawk and a trowel. I think I’m incapable. I pretty much used a mix of a 6″ spackle knife, a 10″ drywall knife, a paint roller, a Magic Trowel, a spray bottle, and lots of rags. Also, corner trowels are VERY necessary. I really can’t recommend the Magic Trowel enough. It saved this project and my sanity.

I know that’s not specific at all, but it’s kind of all I have! I’ll get much more detailed with how I go about plaster repair when I’ve done more of it and really have a technique down, but I don’t want to pretend to teach anyone something I barely know myself just because I pretend to be good at this stuff.

Getting the walls to this point feels like a huge step. Next up is primer, paint, wallpaper, and the floor! The fun stuff.

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