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Casting Techniques: Virtues and Vices


We tend to extoll the virtues of precast, but is cast in place evil? Is it a necessary evil when seams are forbidden? Join us in a balanced exploration of cast in place versus precast, the pros and cons of each, and the many considerations involved.

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Jeff Girard (00:03):
Well, good morning.

Caleb Lawson (00:04):
Well, good morning everybody. Oh, sorry. We just did that at the same time. Sorry. Welcome to The Maker & The Mix podcast. I’m super excited to have any and all of you on and it’s on this sunny day. It’s actually kind of a sad day in my hometown of Canton. We’re gathering at noon in the park to hear the last whistle from the mill as it’s shuts down. So we have a paper mill in our town for whoever of you don’t know, and it is shutting down after 120 years, not due to lack of profitability or productivity, it’s kind of a selfish move by the company. But anyway, a lot of opinions there. So anyway, I would join you from Canton and from Raleigh and excited to have you on. We’re going to be talking today about the virtues and vices of different types of casting techniques.

Caleb Lawson (01:00):
So as you know, I produce entirely shop made GFRC, and we’re also going to be talking about, so we’re going to be talking about that as well as cast in place and the reasons you would do it, the reasons you can do it, the reasons you wouldn’t do it, and vice versa. So lot of a topics to kind of go over today. So hopefully we get some questions and we can talk through that. But Jeff, I’m going to let you kick it off with what you have to say about cast in place and cast in shop.

Jeff Girard (01:33):
Okay. So like Caleb, 99.9% of everything I do and have ever done is precast. When I got started doing this almost, well next year it’ll be 25 years. So quarter century ago,

Caleb Lawson (01:50):
We need to have a party.

Jeff Girard (01:51):
That’s a long time ago. I did precast because I had no clue of what was involved in casting in place and I didn’t know how to finish. To me, any kind of cast in place was basically you got to know how to trowel and that was the be all, end all. Everything you needed to know is you got to know how to finish the concrete. And what we’re going to talk about today is there’s a lot more to it than just that. It’s important, but there’s a lot more to it than just knowing how to finish concrete. And I think that’s the one, the sub story we’re going to say is that’s a pitfall a lot of folks fall into is thinking that they just have to be good at troweling. So more on that later. So precast, let’s start there. So an overarching view we’re we’re going to talk to folks who maybe your seasoned pros, you’ve been doing this for a long time.

Jeff Girard (02:43):
The ins and outs, you already know this. We deal with folks from all over the world with all different backgrounds from DIY homeowners who they call concrete cement. And they think it’s the same thing to folks who have been doing this longer than I have. So a big range of people. So with precast, the whole idea is you do all your work in your shop where you have a controlled environment, you control everything, all your tools are laid out, everything you need is there, nobody’s bothering you, and you do all the work is completed before you ever bring it to the job site. So that’s it in a nutshell. So if you had to sum it up in a single word, you have control over everything how you, you’re mixing, you’re measuring, you’re casting, how you control the mess you’re going to make, how you seal it, everything in contrast with cast in place or pour in place or in situ as folks in Australia like to call it.

Jeff Girard (03:55):
And other parts of the world. Basically you are doing all the work on site, wherever that site work is, and there are good reasons for considering doing that and there’s some good reasons to not consider doing that. But be that as it may, you’re doing all the work that means you’re making the concrete or you’re having the concrete delivered. You are doing all the form work, everything is on site. So that site, the conditions of it are going to affect how you do the work, how easy it is for you to do the work and all that.

Caleb Lawson (04:34):
Yeah. So one thing, so quick question. In what situations have you found that people, I have found that people primarily are going for cast in place for one reason and one reason only. Now they’re not really considering all of the ancillary details and things like that necessarily. Maybe they are because there are a couple of guys who are doing this phenomenally well and I want to be real clear on that. But the primary reason in my personal experience that anybody in our trade or craft would do important in place, cast in place would be because the client doesn’t want seams, right?

Jeff Girard (05:16):
It’s aesthetic reason.

Caleb Lawson (05:17):
Exactly. I, and I know a few guys who get around that with GFRC with some really creative solutions. I think I saw Josh Thel did a really unbelievable kitchen. It was like a C shape and it was like eight feet on a leg and he actually got that sucker in into play. So there are definitely an ambitious guys out there that are doing seamless things that should have, should need seems. But yeah. So let’s talk about seams for a minute and how that relates.

Jeff Girard (05:51):
Absolutely. So a seam is a control joint and in the larger world of concrete construction, whether you’re dealing with warehouse floors or roads or walls or anything like that, concrete has control joints placed in specific locations for specific reasons. And one of the main reasons is your environment’s going to change, your environment’s going to move ground settles, temperature changes effect expansion contraction. But most importantly is with few exceptions and there are some exceptions. All concrete shrinks over time and shrinkage occurs for two main reasons. One is moisture loss through evaporation. As the hardened concrete continues to cure, it’s going to lose moisture because it’s got more moisture in it than it’s external environment. So there’s a natural tendency for the moisture that’s in the concrete to evaporate things dry out, we g all get that. There’s also a chemical drying that happens, it’s called autogenous shrinkage, where as your Portland cement starts to undergo the chemical reactions that form all the stuff that holds concrete together, the end result is the part of the water is consumed in that chemical reaction.

Jeff Girard (07:21):
And the net volume of the things that are created is smaller than the starting point. So your concrete naturally chemically shrinks. Now these can be compensated. There are special admixtures that are called shrinkage, compensating admixtures, which actually cause your concrete to expand a little bit as it cures to compensate for that. And it’s a delicate balance, but it’s not necessarily a shrinkage reducer, it’s a shrink no shrinkage. Producers are different things. These are actually expansion and some of you do flat work and things like that might have ever heard of type K concrete where it’s an expansion component, expansive component, and it’s related to CSA type cements. I’m not saying that CSA cement does that, but I’m saying it’s chemically related to that process. So there are situations or special situations where you might do a big warehouse floor, maybe you’re doing a freezer warehouse and you have to pour a hundred thousand square feet of concrete.

Jeff Girard (08:25):
It can be done seamlessly, which is quite amazing. But it’s a very carefully engineered process. It’s not something you just casually grab a bag of this and toss it in and expect the best. So this is not a very specialized tuned situation. So it is possible, I’m not saying all concrete, but most concrete, especially the concrete we deal with is going to shrink. So the notion that a customer, and I’ve personally had a customer ask me this, I don’t want any seams, okay? Seams are a place where you are letting the concrete do its thing. You’re going to let it move, you’re going to let it shift, you’re going to let it flex, you’re going to let it expand or contract at a known point. And that known point is both structurally and aesthetically acceptable. You’re setting, we’ve talked about setting the expectations. When you have a scene, you’re setting the expectations that any kind of movement is going to be at the scene.

Jeff Girard (09:27):
We know what it’s going to look like, we know what it’s going to be so we can accept it. If you create concrete and you don’t account for the fact that concrete’s going to do what it wants to do, what it needs to do, it’s going to crack. And we’ve already talked about cracks. There’s flex cracks and shrinkage cracks, map cracking, things like that. Well, if your concrete shrinks because you cast a 50 foot long stretch and there’s no seams and you didn’t account for the fact that that concrete is over time going to get shorter, that got got my hands in frame, that concrete is going to make a control joint, it’s going to make a seam. And we call that a crack. And I’ve seen it, I’ve seen it in pieces that I’ve done. I made the client client aware, Hey, you want a 30 foot long bar top and it’s in an outdoor situation, you’re probably going to get a crack they don’t want to seem so they’re going to get a crack.

Jeff Girard (10:24):
So that’s just the nature of the beast. And that’s kind of one of the things that are you need to be aware of when you choose to do concrete in certain situations. And it also applies to precast. So it’s not unique to cast in place, it’s that with precast by definition, we are making pieces in discreet sizes and bringing them in and oftentimes our ability to transport it, and you already mentioned this, Caleb, our ability to transport it or to get it in the job site dictates how big of a piece we can make. I mean, you and I just made a piece in class, we did a 16 foot conference table, and for those of you who haven’t seen it, it’s on our Facebook group and on the C C I website and stuff like that, and I’m sure it’s on Instagram, we chose that size because your casting table is 16 feet four inches long. So there was a

Caleb Lawson (11:15):
Limiting factor right

Jeff Girard (11:16):
There, limiting factor. So had you had a 20 foot piece, we could have made that table 20 feet because we had the room for it. And structurally that’s possible. So external factors dictated the size of the piece. So if we had, it’s only one piece, so it’s seamless true, but if we had two of those and we had to put ’em together to make something 32 feet long, we’d have one scene in cast and place. You’re kind of unlimited as to what you could do. That doesn’t mean you should do it. So that’s kind of the main talking point here is talking about the Seam sea fellow. Well, and

Caleb Lawson (11:51):
Before we dive too much further into it, I really want to be super clear that we’re not bashing cast in place. Absolutely. There are applications for ad nauseum and I don’t personally believe I have the training, the skillset, I should say, I’m not a good finisher, right? So I am educated and trained in what I do. I have not delved into that realm. And there are a few reasons for that. A lot of what we mentioned control over your environment is the biggest factor for me personally. But I know some guys, I mean I’ve seen, there’s a studio in Australia, I believe it’s called Hungry Wolf Studio, that’s just doing some incredible cast in place stuff. And I just want to make sure that we’re being fair right to the people who are doing it really, really well because they do

Jeff Girard (12:47):
Exist. I know some guys on Dallas Mexen in near Sydney, he does phenomenal work and he specialize in cast and place. He’s an incredibly talented man, does beautiful, beautiful work. And he’s really good at it because he understands what is involved in doing it well. And

Caleb Lawson (13:07):

Jeff Girard (13:08):
That’s kind of the point of this podcast is to touch on the things you need to think about that some folks may not even be aware of. If you’ve ever been to one of my classes, you’ve maybe heard me say this, everybody knows what they know and you’re aware of the things that you don’t know, but it’s the vast universe of the things that you don’t know, that you don’t know that can sometimes come out of the dark and bite you, bite you and it hurts

Caleb Lawson (13:39):
You. Dunno what you dunno.

Jeff Girard (13:40):
That is what we’re addressing are the unknowns that you’re not even aware of. So kind of what sparked this whole topic was a few days ago on one of the internet groups, discussion chat forums, things, there was a gentleman who asked the question about curing and it was related to hearing a cast and place piece. And so I added my comments about how to, he was worried about cracking and he asked about should he periodically wet the surface. And I had made some comments about how generally that’s not a good idea because when you let freshly cast concrete dry out and then rewet it, that can actually cause that wet and drying cycle can actually create more surface cracks than if it’s kept continually moist. So that initial topic discussion led to a private conversation between him and I asked him this question, so why are you doing cast in place?

Jeff Girard (14:49):
Because for me, with a lot of experience in precast are, to me, from my perspective, there are fewer pitfalls with precast because I have more control than with cast in place. And so his response was that he works with concrete, he’s a concrete finisher, and because he has this skillset of knowing how to finish concrete, he felt comfortable with it. He felt comfortable with it. So he made the decision to approach this project from that perspective. And added to that his customer didn’t want seams, which are all both legitimate reasons. And I said to him, I said, well, translating your skills and your success with conventional concrete pouring floors, pouring Dr driveways, sidewalks, patios, that sort of thing, flat work doesn’t necessarily guarantee that you’re going to be successful when you translate that process and those skills to something a little bit different or a lot of bit different when you’re doing a countertop.

Jeff Girard (16:03):
And the main difference is you might be using a different kind of concrete, or if you try to use the same concrete, you’re going to have to adapt it because we’re making smaller stuff, especially thinner things, floors and driveways and sidewalks are usually four inches thick or a hundred a millimeters thick or thicker, six inches, 150 mil millimeters or thicker. So when you’re dealing with a very thick mass of concrete, especially something that’s cast against the ground, whether it’s against the plastic moisture barrier or just cast against the ground, that concrete is in a different moisture state than it is up in the air on form work and things like that. So you shrinkage becomes very, very important knowing why does concrete, hold on, sorry. If you hear my dog barking in the background, he’s talking to the people walking their dogs on the street.

Jeff Girard (17:00):
You’ve heard my dog a million times at this point. Why does concrete curl? What causes curling? What causes shrinkage? And we mentioned that it’s moisture loss if you’re not aware of the fact that one face of your slab, if you’re leaving the form, if you’re casting on forms that stay in place, you’ve got cabinets, you put down plywood, you cover the plastic, you’ve now created the same kind of situation you create. If you lay down plastic off the top of your compacted gravel and you pour say a basement floor, it’s kind of the same thing. But what’s different is a basement floor might be four six inches thick, whereas a countertop might be an inch and a half thick or two inches thick as you get pretty thin. The difference between the side that’s against the plastic that stays essentially permanently moist until it eventually drs out in years to come.

Jeff Girard (17:58):
And that top surface that’s open to the atmosphere, that’s only a little bit. And when you have a very high moisture gradient and very thin section, you’re going to get a high chance that that top is going to, as it shrinks in, we just talked about shrinkage, it will shrink. You’re going to get curling. All right? And the thinner that piece is the more that curling is exaggerated. And so if you’ve got concrete past against the surface and it’s kind of locked down because of the geometry of the piece and the geometry of the edges and the geometry of the shape you potentially build in cracks to come cracks that might happen in two weeks, in two months or two years. And that’s what I’ve seen in the past. And that’s kind of what we’re talking about here, is be aware that just because something looks great when you’re done sealing it, you walk out the door and you take your photos and you upload ’em to Instagram, how it looks then does not mean that’s how it’s going to look forever.

Jeff Girard (19:05):
That’s the best it’s going to look. Your skill, in my opinion, your responsibility as a quality maker is to make sure that everything you do, every decision you make, every ingredient you put in to your concrete, every step you take is there to preserve that quality that you’ve poured into that work that your customer’s paying for. And that’s kind of what we’re talking about. It’s like you can do it, but you got to pay attention to it. And the folks who do great work and are successful at it, they do that and we want you to do that too. So in precast work, and you can comment a lot more on this, it’s a lot easier for us to do that because again, we have,

Caleb Lawson (19:49):
I totally agree. I mean, there’s one element I’m kind of intimidated by the concept of not being in control of my environment. And I’ve been among those who have made some pretty ambitious decisions as far as what I’m willing to do in precast GFRC. I’ve done 22 foot pieces for interior living room situations. I’ve done 20 foot pieces that had to be flown seven floors onto a pool deck. I’ve done really ambitious GFRC projects primarily because I didn’t, I’ve done things that were called as cast in place. So am I going to do that? I’ll do it this way. You can still have your no seams. So I’m certainly accustomed to the client who doesn’t want seams and doing my best to accommodate that. Now if it goes around a pole, yeah, that’s a different story. I’ve had bars where it went around the pole or whatever, and so I’m like, well, you’re going to have to have a scene. But I kind of offset them around the pole, so wasn’t, so there are definitely decorative ways, and that’s something we can address too, is that seam aren’t bad. You know, can have massive pieces that still need seams. It’s like you can have a 40 foot bar and only have one scene and lots of creative as impressive

Jeff Girard (21:14):
Creative ways to make a scene, not just be acceptable, but be a decorative focus. I’ve inlaid copper and stainless steel, absolutely l e d, unli acrylic in seams. It can be the focal point. And I’ve had people pay me for seams. So they’re not just a necessary evil.

Caleb Lawson (21:35):
I think it’s all about how you frame it and all about how you frame it all about how you communicate with the client. Everything about those types of decisions are a frame of mind for the client. So if they’re telling you, I don’t want seams, oh my gosh, they’re horrible. Well then, I mean maybe there’s a design element in their home that you could actually be like, actually that’s really cool and we could do that. I had a client one time that asked me for a 22 foot dining room table. And the logistics were interesting because the only time in the build process that there was going to be enough room to get a piece that large into the home was during framing. So that table would’ve had to have been made during framing and actually be in place in the dining room pre anything

Jeff Girard (22:22):

Caleb Lawson (22:24):
And that’s really high risk. And so it was very, very expensive. And the response was, what? That’s not worth that kind of investment. Cause this was a vacation rental home. And so the client had me do make two 11 foot pieces instead, and it was a marbled table. And so I made kind of a funky rock face scene as a design element. And so it looks great. What you have today is a really cool 22 foot dining table to everybody, and nobody really cares that there’s a sea in there because it’s part of the design. Yeah,

Jeff Girard (23:01):
I think that really gets to the heart of it is asking why does the customer want seam not want seams? And it may be just a knee jerk reaction against them, or maybe they think that it’s going to be hard to clean or they think that it’s going to be problematic because maybe they’re thinking of tile grout that always gets nasty. There are lots of solutions, there are lots of folks have their own solutions for dealing with seams. I’ve personally never had issues with cleaning or anything like that because of the way I make them. But a seam is not necessarily a bad, and certainly from a precaster standpoint, they always exist. Now, not every piece, a single piece that’s like a bathroom vanity or this table or something like that doesn’t have seams by its very nature. But seams are sometimes your friend and choosing cas in place simply because the customer doesn’t want a seam is not always the best solution.

Jeff Girard (24:16):
And the very first official cast in place job. I used to teach a cast in place job class with Bob Harris 17 years ago. He’s well known in the decorative concrete industry, extremely talented. He teaches flat work and decorative concrete stamping and staining and etching and all cool things like that. So he is extremely, extremely knowledgeable and he’s a world renowned expert in decorative concrete. So I was very honored to be teach alongside him and I learned a lot from him. And the approach of pass and place, the things you have to pay attention to, the pace of the work, your knowledge of your material and the choice of your mix design become really become accentuated and come to the forefront. So I want to step, kind of take a lateral step sideways and just do a very broad, very brief overview of the difference between what’s involved in precast and what’s involved in cast in place.

Jeff Girard (25:24):
So with precast, you’re in your shop, you’ve had your forms built, and that’s your base. That’s where you’re starting from. And then you’re going to go mix your concrete, you’re going to cast it, and then the casting process is where you affect and introduce and manipulate the look of the concrete. So whether it’s poured or sprayed or marbled or you’ve got exposed aggregate or use casting powders or hand press it or whatever. That’s how you create the aesthetics of your piece. And once you’re done casting the piece, you’re filling the forms up or you’re casting a shell where the walls of the shell are built up to be three quarters of an inch by hand packing your backer. When you’re done with that, you cover it, plastic, glean your tools, and you walk out the door, you’re done. So the casting process is usually pretty quick. And if we’re talking about direct cast, you’ve got a vessel sink or a fireball or just a simple flat countertop slab, you make a very fluid self-consolidating mix. You pour it in, you shake, vibrate, tap, whatever, and five minutes later, 10 minutes later you’re done. So yeah,

Caleb Lawson (26:42):
I mean I did island cast and I, we casted in 45 minutes.

Jeff Girard (26:47):
Yeah, it’s a very efficient process and a lot of precasters like that because you can do a lot in one day or you can be done very quickly and have a short work day in cast in place. It’s different. So for those of you who do this day in, day out, have lots of experience, please forgive me if I’m skipping a step or I’m doing things out of order. This is what I’ve seen over the years. Step one, okay, you’re basically in a start and same place. You’ve got your empty forms and you make your concrete. Now the biggest job I’ve ever done and wa did was a very large bar top in a yacht club in the Cayman Islands. And for that we ordered a truck of concrete. Now, this is not ordinary concrete. I’d worked with a plant engineer to tailor the mix to have the properties I wanted.

Jeff Girard (27:35):
And we were going to touch on that in a bit. But 18,000 pounds of concrete came in, a truck was delivered down the chute and wheelbarrow into the building, into the room because it was too big to get to. You could truck couldn’t deliver it just through the chute, through the door. And then we placed the concrete. So once you place the concrete, you spread it out, you fill your forms up and you then screwed the concrete, which is essentially you strike off the excess, you fill in the low spots and in a sense, precast and cast in place are directly parallel with each other. You fill in the forms with your, they’re opposite, but they’re opposite because precast, ja, almost always, but not always, but almost always is upside down. The show side or the side you’re going to show to the customer and install is upside down casting.

Caleb Lawson (28:28):
And the almost is the folks that do upright type casting, which is great. Yeah, cool technique.

Jeff Girard (28:35):
So once in cast and place, the concrete’s placed and screed, the next step is floating. So I’m talking about concrete from the perspective of concrete that has rocks in it. So large aggregate, gravel, whatev, what have you. And the reason why the next step is important is when you mix concrete, it has all different kinds of stuff in it. All those bits and pieces are everywhere. The gravel’s on the surface, gravel’s in the middle, gravel’s in the bottom. And when you finish screening it, it’s still homogeneous, it’s still uniform, top to bottom, and you can’t really finish the concrete that way. Now in two of the jobs that I did on same, in the same location with the same kind of concrete, but for different projects at different times, we were going to expose the aggregate. So it was all going to be ground and polished.

Jeff Girard (29:35):
So once we screed and got the forms nice and flat and full, we were done because we didn’t care what the actual surface looked like. It was going grinded away anyway. But most of the time in cast and place, the way you finish concrete is to tr and in order to tr the concrete, you need to float it first. And the floating pushes those rocks down, it compacts the concrete. And in doing so, it forces the cement paste and the cream up to the surface. And the colloquial term is like you’re bringing the cream to the surface. So you’re squeezing that excess cement paste and sand up to the surface, and you’re building the layer. It’s like you’re fro, you’re, you’re squeezing the cake and the frosting’s coming out, and that’s what you troll. And if you don’t do that enough, if you don’t have enough of that cream on the surface and you don’t push the rocks down far enough everywhere, you’re going to have a hard time. Cause you might have one rock sticking up and as you are trolling it later on, you’re going to hit that rock and it’s going to up and it’s going to make a mess. So floating is an important stage early on in the process.

Jeff Girard (30:45):
And this is where understanding your material and having lots of experience trialing comes into play because now you have to wait in conventional concrete, especially if you’ve seen guys or girls pour a driveway or a sidewalk or what I’ll call a low value concrete. Not that that’s low value as a driveway, but from a concrete countertop standpoint or whatever kind of product you’re making, the kind of concrete WeWork is very, very high value. So truck mix tends to have too much water in it. So you’ll see the driver with the hose squirting it out because it’s a little too stiff. And that’s bad practice, but it’s done. And it usually is okay because we’re not expecting a lot from our concrete, and that’s okay, right? Our expectations a lot higher. Our customer’s expectations are a lot higher. So when a mix that has a little too much water in it gets placed after it’s screed, after it’s floated over time, gravity is causing everything to kind of settle out and it’s squeezing water out.

Jeff Girard (32:02):
And that’s where the bleed water comes from. So gravity’s squeezing the excess bleed water out, and so you’ll get, it looks like the concrete sweating. And in really bad cases, when the concrete is very abused by having way too much water, you’ll actually have a layer of water. You hose it down, that’s really, really bad. And so you got to get all that water off. You got to wait for that water to evaporate. So that’s step one. Step two is what you’re waiting for is that slightly compacted layer of gravel. The more uniformed layer of concrete that’s underneath the cream layer you just created, the 99% of the concrete, it’s going to start firming up. As the concrete goes into its setting stage, it’s not getting hard, it’s firming up. And that’s an important stage because if you start to move on to the next phase, let’s say there’s no bleed water, you’re, you’ve got your cream layer, your water content’s good, and you go, okay, I’m done, done floating, boom, I’m going to go into trolling.

Jeff Girard (33:05):
And you start doing it too soon. What’ll happen is as you’re trolling and trying to spread that thin layer of cream to smooth it out, you’re going to start moving what’s underneath it. And it’s got, that stuff’s going to act like jello or pudding, and it’s just, it’s going to pile up and it’s going to be a mess. So what you have to do is you have to wait for the right stage for everything to start firming up. And a test that I’ve had somebody tell me is you make a slight fist and this little fleshy part between your thumb and your forefinger, you kind of push on your hand there. And that’s kind of the consistency you want that concrete to be. Now

Caleb Lawson (33:46):
That’s kind of like the,

Jeff Girard (33:48):
Is it medium rare? Is it rare? Yeah, yeah. It’s like, right, right, exactly. That’s we’re going to learn that. That’s burn. Well done. That’s like

Caleb Lawson (34:00):
Medium. Well, it’s

Jeff Girard (34:01):

Caleb Lawson (34:03):

Jeff Girard (34:03):
Yeah. Yeah. So you’ve got to let that cream layer, that thin layer of sand and cement that you’re going to be actually working and reworking to get to the right consistency. And there’s two things that happen. One happens faster at the end of the other. Yes, the concrete is starting to undergo its setting process, and that does firm things up. And because the bulk of the material has rocks and sand in it, it’s very noticeable. But that cream very fluid and mobile, the thing that’s really happening is it’s starting to lose excess moisture. It’s jarring out. So as your water content in that layer goes down, it’s going to naturally get stiffer. And that’s why a lot of concrete has too much water and because it starts out too stiff and you add water to loosen it up. Okay, bad practice by the way, really bad practice, but it’s done.

Jeff Girard (34:56):
So as that layer evaporates, that thin liquidy layer starts to firm up and become more like a soft clay like butter. And that’s when it gets to the right consistency. That’s when you start trialing it. And those of you who do this already understand that. But for those who might be interested in learning how to troll, these are the things you’re looking for is you got to get that concrete to be the right consistency. And you start out with a big trawl. Now, I know when you do floors and things like that, the tools are bigger and different, but by and large, you start with the big travel, the biggest one you can handle that’s appropriate for the scale of the job you’re doing. And then as the concrete firms up, and as you keep working it and reworking and reworking it and remolding it, you work smaller and smaller to the point where you might be using an eight inch trel, eight, eight inch, little mid tr, and you’re doing really, really hard.

Jeff Girard (35:51):
There’s hard pressure because that concrete’s like hard clay. And that’s where you start burning the surface. And burning is, it’s a term that really is describing as you have a steel tr, you’re rubbing the steel off and they’re rubbing the metal off onto the concrete, and that’s why it turns black. So if you don’t want burning, you use a plastic T tr and some other alloys that don’t like a stainless steel TR is less likely to burn than a carbon steel trel. All that being said is the tring process is the important way of crafting that. Look, you’re getting very hard surface, you’re reworking a lower water cement ratio layer, which is why a lot of well trialed surfaces are so durable. And as an aside, a lot of clients might say, Ooh, I really love the look of, I want you to acid stain my countertops because I like the look of acid sane floors, and I like how they’re modeled.

Jeff Girard (36:53):
So it’s what they’re reacting to is the modeling that variation of shades. And it’s very organic, it’s irregular, it’s dappled that comes from the trolling process that does not come from the acid stain, the acid stain reveals it. But if you took, let’s say, a precast piece of concrete, I make a very fluid concrete, I pour it into my, slap my mold, I vibrate a little, let it hard and pop it out. I now have a smooth uniform piece of concrete. I put acid stain on it. There’s no modeling. It’s a pretty uniform color. Now, I could fake it by sponging it on and making modeling, but if I ask to stain it like you do it normally pump up sprayer, spread it around, it’s going to look pretty uniform. The uniform, the modeling comes from what you do when you’re remolding it. So some parts of the concrete have a little bit less water cement ratio, a little bit more over here as you smear and stir around where you’re creating the model. And that’s where you’re creating that beautiful look. So

Caleb Lawson (37:58):
Really that’s

Jeff Girard (37:59):
An appeal of cast in place is the finishing process. And that can be done in pre-cast, but it’s not commonly done. But I’m sorry to interrupt you, Caleb, but I wanted to No,

Caleb Lawson (38:10):
You’re fine. So I mean, basically the long and short of that essentially is we have a lot of factors to consider when we decide how we plan to make our concrete. I, there’s a lot from what if the client expect to, what’s your skillset to what’s the situation? Is this outside? Is it 50 feet long? Is it going to need control joints and things of that nature? So I think the encouragement here is get a 30, don’t zero in, I mean that comes later, but get a 30,000 foot view of what the expectation is, what the client needs and what you’re agreeing to accomplish. Because to me, what you’re agreeing to provide to your client needs to be the same a year from now, two years from now, then you know what I mean? So I feel like if I’m going to say I’m going to provide you seamless concrete in this instance, then in two years it still needs to be seamless. And so those are the factors that I’m hoping to really bring out is, and to me, this seems to be the thread throughout our conversations, Jeff, is set the expectations for your client that can be upheld for a long period of

Jeff Girard (39:35):
Time. Absolutely.

Caleb Lawson (39:36):
You’re not just trying to get a quick, not that any of you are, but you’re not just trying to get a paycheck and get out of the house and then never talk to ’em again. I mean, obviously that’s the most ideal client, but you want that to be because their expectations have been satisfied. And so to me, that’s one of the biggest things that you and I push hard is we want those expectations to be satisfied and we want them to be set properly. And this

Jeff Girard (40:04):
Applies both to precast and cast in place. That’s important to point out is this applies to both. And the way you do that is you have to be aware of the situations and the pitfalls and the considerations of the choices you’re making. So if you don’t feel comfortable with what you know can do and provide and the assurances that you can give because a customer asks you to do something that’s outside of that comfort zone, then it kind of falls back on you to say, no, you can’t have that. Or Here’s a better alternative because I know it’s going to make you happier. Ultimately, the concrete’s going to do whatever the concrete wants to and needs to do.

Caleb Lawson (41:01):
Well, it’s kind of like timelines. A lot of times you’re going to be demanded, oh, you’ve got to get this done by X, Y, or Z date, and maybe that date is four days from now. And general mean back in the day, I used to be like, oh gosh, I guess I got to do it and I got to figure out how to do it be horrible. And I’ve pulled some stuff off that maybe I shouldn’t have, don’t know. But the bottom line is a no is a complete sentence. B, you’re going to be happier long term client if you let me do this in a timeframe that’s acceptable to the material, can I rush things? But that’s where errors come into place. That’s where there are some pitfalls to rushing the jobs. And so all of that to say, setting those expectations and being willing to stand up for you and your product is worthwhile.

Jeff Girard (41:57):
And that’s what makes professionals expensive because they have deeper knowledge and vast experience to know better than ultimately the customers that are paying them. Otherwise the customers could do it themselves. They may not be willing to, but that that’s kind of what sets a professional apart from a DIY, is I’ve made the mistakes or I’m aware of how to prevent those mistakes. Whereas a homeowner or somebody who’s a novice really has to lean on other people to hopefully give them, paint them the complete picture so that they’re successful. Otherwise, it’s this, it’s a sad and all too common situation of I thought it was going to turn out and then man, all these problems happened. And ultimately that is why I got into doing what I do, is I didn’t want to just copy other people’s problems just because somebody did it and they’re sharing their experiences. I mean, it’s actually good experience or that I’m going to be successful mimicking what they’ve done. I need to know a lot more beyond why they made the choices they did or what they did. Well, no,

Caleb Lawson (43:12):
You need to know far beyond what choices they made because somebody could be in the industry for, in whatever industry they’re in for 20 years and you know, don’t know what their experience has taught them. That it’s like, oh, here’s what I do. Well,

Jeff Girard (43:29):
That’s going back to what and what you don’t know, but you don’t know what you don’t know. So if you’re only sharing experience, you’re only showing sharing what you know and what you don’t know, but you have no clue of all the other things. And that’s where relying on deeper knowledge sets. And that’s kind of what we’re sharing here, is don’t be afraid of cast in place, but really approach it from a much deeper process in just knowing how. It’s more than just knowing how to travel.

Caleb Lawson (43:59):

Jeff Girard (44:00):
Just knowing how to pick the right concrete, how to make the best decisions for your customer, to be aware that when you start to do thinner pieces of concrete, a lot of the situations that don’t even pop up in thicker concrete now become major issues. And that can bite a lot of people. And I’ve seen it bite a lot of people. So be aware of that and talk to people who have experience talk. And as with this gentleman that I was talking about, I shared a lot of information about precast. I said that, look, I got all his free information here. Take a look just so that you can start to make better decisions for you and your customer, because ultimately he’s got to deal with the customer. If they have an issue, I’d rather prevent a problem than try to fix it later on.

Caleb Lawson (44:48):

Jeff Girard (44:50):
I think there’s a good place to stop for today. Yeah, I think

Caleb Lawson (44:52):
That was good. That was a lot of information, so watch it a couple times. But yeah, to those of you who join us and join us later, super grateful to have you look forward to talking to you next week. Give us a shout and shoot me or Jeff an email and ask us for topics. If you want to listen to something specific, if you want us to talk about something specific or you got a question, shoot us an email. I think info concrete countertop could get us that. If you so shoot

Jeff Girard (45:28):
Us. We want to engage with you guys and we’re not getting a lot of that. So let us know your thoughts and all that so that,

Caleb Lawson (45:38):
See you next. Awesome. See ya.

Comments are closed.

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