All posts tagged: Concrete

Adding Self-Leveling Concrete to a Basement Floor!

This post is a paid partnership with Lowe’s! Thank you for supporting my sponsors!

If you caught my post yesterday, you know that I’m back at work on the long-suffering Bluestone Cottage, and that the first space I’m really tackling is…THE BASEMENT. I’m finishing a basement! This is a first!

This is where we started so many eons ago. It was awful for many reasons.

It’s made less awful by the addition of work lights, not to mention the passage of time, but it was really, really bad. Aside from all the junk, there was also a defunct oil-burning boiler, obsolete heat pipes, rotted posts, termite-damaged joists, and—to my surprise—a moldy falling-down drywall ceiling and CARPETING. WALL-TO-WALL-CARPETING. That carpeting probably tops the list of grossest things I’ve ever removed during a renovation, and that includes mummy squirrels, a tub that someone died and partially decomposed in, and an enormous pile of 90s porno mags for people with an affinity for extremely large-busted women.

When I was designing how this house would work, I decided it was just too small to dedicate living space to a washer and dryer, but I still wanted it to have both. That left one option: basement laundry. I’ll let that shiver leave your spine. I know that’s not most people’s ideal, but it’s better than no laundry at all and I’m determined to make it nice, finished-feeling, and an asset rather than a bummer. It’s 200 square feet of potential, and I’m going to try to make the most of it!

Finishing a basement in an old house makes me a little nervous. In part because I’ve never done it, and in part because back in the day, these spaces were never meant to be finished in the way the rest of the house was. A lot of old basements, like mine, are so clogged up with wiring and plumbing and support posts that the idea of finishing it feels borderline ludicrous. And since my own home renovation is such a long-term project, I frequently need access to the utilities as new work is added and old work is removed. The basement just can’t be a precious space in many old houses—but clean and comfortable and utilitarian all feel like achievable goals, especially here where all the utilities are brand new.

Totally different angle (that nook is over to the left, just out of frame), but this is where I started a couple of weeks ago. It’s hard to tell from the picture, but this does actually represent major progress, just not the beautiful kind. It happened in fits and spurts. You’ll notice a MESS of wiring waiting to get tied into the panel (all new, though!) and a bunch of new pex and PVC plumbing that will eventually make 1.5 bathrooms, a couple of hose bibs, a kitchen, a washing machine, and a hot water radiator heat system all function. LET. US. PRAY. Also, all the walls are now framed for insulation and finishes,* and the floor joists above have been reinforced and the old support “posts” have been removed. SO IT LOOKS LIKE GARBAGE but it’s actually a lot of money and work to get to this point of dungeon horror.

*We framed the walls in pressure-treated 2x4s. I learned later that this was maybe overkill—you’d definitely want to use pressure treated for the bottom plate as it’s in contact with the concrete, but vertical supports are typically done in fir or white lumber unless they’re actually affixed to the masonry. Oops. Now we know.

NOW LET’S START MAKING IT PRETTY. PLEASE. I NEED TO SEE SOMETHING NICE-ISH. It’s not good for your brain to have a job site look like this for long. As me how I know.

VERY CLEARLY, THERE IS A LOT TO DO. And I can’t be spending a ton of time or money on it, it just has to get done. So first order of business? Getting the floor in shape. It didn’t necessarily have to come first, but for my sanity it did, and also the machines are being delivered soon and I want to be able to have the delivery guys bring them downstairs because it’s going to be tricky getting them down.

So. Floor. On the bright side there was already a concrete floor, so we’re not starting COMPLETELY from scratch, but it was ROUGH. Very rough—think some crumbling, some cracking, some holes, various old patch jobs, and not remotely flat or level. I think part of making this basement laundry plan work lies in making sure all parts of it feel nice and clean-able, and the existing floor was anything but! It was well beyond the point of any kind of quick and easy solution (like just painting it, or an epoxy kind of resurfacer), so it seemed like a job for self-leveling concrete as a first step.

Now, I’ve used self-leveling concrete a couple times over the years, and I’d always been under the impression that it was all supposed to be used as an underlayment for something else—like a floating laminate, a stick-down tile, a ceramic tile, etc,—but not as a finished floor surface. And that does appear to be true for some of these products, but some sleuthing confirmed that Sakrete’s Fastset Self-Leveling Resurfacer can actually be used either as an underlayment or as a wear surface! I’m totally fine with a nice concrete floor for a basement, so my plan became to just seal the concrete rather than going through the time and expense of adding a whole layer of additional flooring. Groovy.

That being said, actually installing the concrete is a bit more involved than just mixing and pouring! There are a lot of products to compare and instructions for each to follow for best results. Note how I say best results—SOMETIMES it’s not possible to follow every single instruction or meet every single ideal condition, and you know what? SOMETIMES you just have to do your best. My experience with concrete has been that it’s more forgiving than package instructions might lead you to believe, and you can still get a very nice, long-lasting and good-looking result without necessarily achieving the OPTIMAL result or performance (we’re talking about cosmetic work here, not load-bearing). It’s ok. Sometimes you’re working in an unheated, uninsulated old house in upstate New York in January with a $100 propane heater, trying to make it work. FOR INSTANCE.

So here’s what I did:

STEP 1: PREP.

The most underrated phase of any project is the prep. It’s no fun but you can’t skip it. With self-leveling concrete (or really any kind of coating at all, like paint!), you want a clean and stable substrate for the new material to bond to—which in this case was a tall order.

I thought I could prep for the concrete in a few hours. It took like four days. I hauled—and this is not hyperbole—on the order of about 150 pounds of just DUST out of the basement. Dirt and dust and sawdust and other detritus captured by the Shopvac (I have a huge Shopvac, but I find that I really prefer this little guy when working in a small space). I swept. I vacuumed. I swept some more. I vacuumed some more. I scrubbed the really dirty areas with a wire brush. I vacuumed some more. I did my best. The instructions mention mechanically profiling the surface to promote adhesion, but I didn’t do that. I also didn’t use any special chemicals or anything, since I needed the floor to be dry enough to accept the primer and concrete—outdoors a pressure-washing or something might be a better option than for indoor work where there’s nowhere for water to drain. I just cleaned as thoroughly as I could and called it good enough.

STEP 2: PATCH

All of my cleaning efforts exposed a few areas of major damage in the floor—in severe spots, right down to the dirt underneath the slab! Yikes. This is not how you’d pour a slab today, ha! But it’s what I’m working with, and excavating it all out and installing a vapor barrier and gravel and a new few inches of reinforced concrete is very much not in the cards.

There are various products around for patching areas of damaged concrete, and I used this one because I had it! I’m pretty sure this came out of Anna‘s basement, meaning this 10-lb bucket of concrete dust has probably been passed around for about a decade now—ha! One of the joys of finishing this house is going to be using up SO MUCH STUFF I’ve accumulated either with this house in mind, or leftovers and scrap from other projects. It’s highly motivating.

Just follow the mixing instructions for whatever patch product you’re using and make sure you give it time to cure before moving onto the next steps! For this step, I used this concrete binding adhesive in place of water for extra security. The dark areas are what I patched.

STEP 3: PRIME

It’s probably a good idea to vacuum again right before priming. Again, priming will depend on the concrete product you’re using—mine called for the use of a self-leveling bonding primer, although it didn’t specify a specific product. Of course it didn’t!

After some hunting around, I landed on this MAPEI Primer T from Lowe’s, which appears to be for this very thing. It was actually back in the flooring section with thinset and grout and stuff, rather than up by the concrete in the building materials area. Just FYI!

For added excitement, the primer is hot pink! The package instructions said to water it down by about half for this kind of application, so that’s what I did. Watered down, it’s very thin and sticky, like a glue.

Thinning it in a bucket made it easy to just pour some on the floor and roll it out with a 9″ rough-nap roller to spread it, aiming for a nice even coat. This stuff is a little tricky—it’s dry and ready to go in a few hours, but you want to lay the concrete within 24 hours of priming or they recommend re-priming. This gives you a 20-ish hour window to pour all the concrete.

STEP 4: POUR

Following the instructions on the Self-Leveling Resurfacer, I measured out my water and mixed in my concrete—each 50-lb bag fits nicely in a 5 gallon bucket. The package specifies 2 minutes of mixing, which is not a short amount of time when you’re standing there controlling the drill, so it’s good to use a real timer.

Speaking of the drill, almost immediately I knew I had a problem! I thought I could get away with using my regular drill, which was a mistake (I do love that drill, though. All my Porter Cable tools have been such workhorses, and they’re really reasonably priced. Just not for mixing concrete). Then I thought I could get away with the more heavy-duty hammer drill that I have for occasions such as mixing joint compound, and before long that one was emitting smoke and not at all cutting it. So I got through three bags of concrete before calling it quits, and deciding I needed to pick up a more powerful mixing drill.

One tricky thing to keep in mind is that for a solid slab, as far as I understand, you really want to do the pour in one take. If you can’t for some reason (like if your drill is weak and Lowe’s is closed), it’s better to re-prime and re-pour over the section you already did than try to blend a dried pour with new stuff. Oof.

ANNNNNNNNND, curveball! The electrician finally got back to me. They could be there the next morning to finish tying all the rough electric into the panel (which I’ll need in order to close that wall), get the recessed lighting powered up so I could stop dangling work lights all over the place in this dark basement, and add a few outlets around the room since I wasn’t especially focused on the basement when they did the initial rough-in and didn’t specify them.

When the hard-to-get-ahold-of-tradesperson says jump, you ask how high and rearrange your whole life to accommodate.

That morning, the area I poured looked like this, which was VERY exciting. It was…relatively smooth (that huge hole was in the middle of that floor!). Solid. Dry. But also very…grey. And very…flat. Which is how it’s supposed to look, but I guess I was hoping for something with some more variation and movement. This was more like someone spilled a thick layer of grey paint on the floor. Hmmmmm. Something to stew on!

So the electricians did, in fact, show up, do all the things I asked, and it was a relief. Time to get back to work on this floor.

PSYCH!

ANNNNNNNNNNND, then the plumber got back to me. He could be there the next morning to finish a few little undone things with the rough-in, and take a look at re-routing some of the more lazily run pex through joists and in bays rather than on the surface of the joists, where I’d like to be installing a ceiling.

Floor can wait, I guess.

Morning turned into afternoon, and the plumbers showed up. They got to work. There wasn’t enough time in the day left for them to finish, so they’d be back in the morning.

Morning came. Midday came. Afternoon came. Plumbers cancelled. Next morning. Oy vey. I occupied my time by talking about my puppy.

The plumbing took all of the next day. And then he was missing a part, so he’d be back the next morning. I JUST WANT TO POUR MY FLOOR ALREADY EVERYONE GET OUT OF MY WAY. These things happen.

So, with everyone out of my hair: take two. Re-clean it all. Much easier with that layer of bonding primer.

Re-prime the floor. This was also easier the second time around, and used about half the amount of product because the concrete isn’t as porous with a coat already on it.

Like I mentioned, I really needed a more powerful drill to handle mixing the concrete, so I picked up this DeWalt hammer drill from Lowe’s which was on sale for $99! Not bad! It’s 10amps and didn’t struggle at all as I went through bag after bag, much to my relief. It’s fitted with this mixing paddle, which is recommended for this type of concrete.

I also decided I wanted to attempt something different than the solid grey look of the self-leveling resurfacer, so I bought some powdered cement pigment! I read in a couple of places that using regular latex paint in place of water to tint concrete also works nicely, but I figured I’d stick with the product that’s actually designed to do this job instead. I wanted to warm up the color—kind of an orange-ish yellow-ish brown-ish beige-ish, maybe?—so I got colors called Red, Terra Cotta, and Buff. I figured if I combined them I’d get something close to what was in my brain, and if I was a little inconsistent between batches I could blend as I went to get some variation across the pour. I used a 1/3rd cup measuring cup to measure my powders, and about 1-1.5 cups of powder per bag of concrete. I’d suggest buying more than you think you need of any product in this post including the concrete so you don’t run out, and then returning what you don’t use.

To mix the concrete, I found it easiest to measure out the water first, mix that with the pigment, and then add about half the bag of concrete and mix. This should combine quickly and easily. Then add the second half and mix for two minutes, pausing to scrape around the sides where powder may not be getting incorporated properly. It’s about the consistency of cake batter. It’s tempting to add more water but you really shouldn’t because it’ll affect the strength as it cures. A white film on top of the concrete as it’s setting is an indication of too much water.

If you can wrangle a second set of hands, I’d recommend it. If you have one bucket mixing while the other is pouring, the whole process will move faster and speed is pretty key here. Each bag has about 25 minutes of working time, and you want to keep a wet edge throughout the process. Obviously don’t work yourself into a corner, but try to start in the high spot if you can.

If you can’t wrangle a second set of hands, don’t despair. Someday we’ll both find friends who want to play concrete with us, just not today. You got this. Don’t need no man.

Now we’re cooking! I stand by my pigment ideas, but I wish I had spent time making up samples and letting them dry and adjusting as-needed—at this point my timeline was blown and I just wanted to get it done and I couldn’t tell whether the color would change a lot as it dried, or not, and I just kept moving and embracing the mystery of it all. Jesus, take the wheel.

(There’s also plenty you can do to change the appearance after the pour, so don’t freak!)

Working by myself, it took 3-4 hours or so to mix and pour all of the concrete start to finish. Then, at the end, I was feeling a little bonkers and like the floor was still looking kind of…flat, so I started using my hands to kind of fling droplets of water onto the surface for the splatter-y effect. This is…not part of the instructions. It’s called CREATIVE LIBERTY, OK?

Interesting. Very interesting. I’m not sure. The stakes are low here; I am not concerned.

Again, to be clear: the “self-leveling” part of the “self-leveling resurfacer” is only partially true. It levels out to a smooth texture on its own, but it doesn’t really level the floor on its own—it does kind of maintain the pitches and contours of the substrate. You’re also not supposed to apply less than 1/8″ or more than 1″—in other words, your floor already has to be fairly level if that’s truly what you’re after. One way to compensate is using a different concrete product to build up really low areas before using the self-leveler, and/or to lightly use a trowel or a 2×4 to skim and level as you pour, starting in the high spot of the floor if possible, although the instructions explicitly state that a trowel is optional and should be used sparingly if at all.

OR, you take my approach, which is basically that dead-on level floors don’t belong in old house basements anyway and clean-able was the whole goal here to begin with, and you’ve pretty much achieved it and that’s a win.

Now that it’s had a couple of days to dry out, I think I like it?! It’s not unlike the color of a bandaid, but the splattery effect came out kind of nice, and most importantly it’s smooooooth! It’s easy to sweep! It’s easy to vacuum! The space feels SO much brighter and cleaner already, and there still aren’t even walls or ceilings.

I went ahead and installed baseboards because I can still insulate with them installed, and it was something to do while I considered a third pour—partly to try again on the color, partly to try to continue to improve the leveling. I decided that 14 bags—a mere 700 pounds of concrete powder— was enough, though, and I’m just fine with this! I’m tired. That being said, the baseboards are level so you can see how the floor still pitches. I think I’ll cover those gaps with a shoe molding and call it a day.

Even though this basement is luckily quite dry, I’m still trying to take every possible precaution against moisture and mold—so for the baseboards, which seem the most likely to get wet should there be any water intrusion, I used PVC boards usually for exterior trim (which, woah, I guess are on major sale right now?! 75% off?!). Also? I ALREADY HAD IT! I was able to rip down scraps and use entirely off-cuts from work on my own house and a couple other projects over the years. It’s not an inexpensive material, so this worked out great—plus there’s one less pile of stuff in my garage! The Cortex hidden fasteners made for this stuff are amazing—screw, plug the hole with a little pre-made plug, and you’re ready to paint! A little spendy, but worth it.


I think it’s best practice to wait 28 days for the concrete to fully cure before adding a sealer, so I’m not trying to screw it up pretending they mean hours instead of days. I did want to get a glimpse of what it would look like with a sealer on it, though, by just wetting an area down a little with water. It does make the color nicer, I think! Still not sure. I want to see more things come together first. But now that the concrete is in place, there are so many options! It could be painted, stenciled, paint-splattered, stained, epoxied, or sealed with a number of different products.

Coming along! For now, I’m going to let the floor simmer a little bit while I move on to the rest of the space—insulation, walls, ceilings, storage, paint—eek! I think this might actually work!

P.S.— I don’t even really know how to begin to respond to all the genuine kindness and understanding and just all-around-amazingness that came my way yesterday after I hit publish on that big ole post. It was a difficult one to write and put out there, and I’m just so beyond grateful and lucky to have this community around me, and that we can all feel safe talking to each other about hard stuff. It’s an extraordinary thing to be a part of, and I cannot thank you all enough for creating it.

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