Description:
In this video, we dive into the world of outdoor concrete countertops, offering valuable insights to elevate your craftsmanship. Join us as we discuss Mix Design and Materials Selection, ensuring durable and stunning outdoor concrete projects.
Discover a comprehensive study comparing the Mix Density and strength of Alpha Pro Polymer versus No Polymer in concrete, guiding you to make informed decisions for your projects.
Curing Best Practices are crucial for perfect results. We also explore the importance of using Breathable versus Non-Breathable Sealers for exterior concrete, ensuring long-lasting finishes.
Avoid common pitfalls, like using Foam Core for Outside, and master the art of Seams for Exterior Concrete, achieving seamless perfection.
Transcript:
Caleb Lawson:
Good morning, everyone. Welcome to a later morning edition of the Maker in the Mix. I had a dentist appointment this morning, so we moved the recording to later. So if you were planning on joining us live, apologies. But yeah, here we are. So Jeff was just telling me about making a hollow truncated cone in 3D software for 3D
Jeff Girard:
Yeah,
Caleb Lawson:
printing.
Jeff Girard:
good morning, everybody. Yeah, I’m still learning real CAD software. Like I don’t have Fusion 360 yet, but I’m using Onshape, which is an online free version that’s very similar to it. And so I’m still learning the ins and outs of it. So I’m actually 3D printing a flow cone right now for testing the slump of mixes. And yeah. So, had success, now I just have to make sure it actually prints. It’s gonna be 16 hours before it’s done. So, it’ll be a while.
Caleb Lawson:
Oh my gosh, what’s the size of it?
Jeff Girard:
Well, it’s not big, but I’m doing extra thick walls because I need to sand and make the interior really smooth. So it’s just like, you know, lots of layers, fine layer. Yeah, it’s not a very big thing, but it’s just dense. And I’m sure there’s plenty
Caleb Lawson:
Yeah,
Jeff Girard:
of
Caleb Lawson:
I’ve got.
Jeff Girard:
things I can optimize. I’m just, it’s like, I just let the slicer do its thing and okay, increase the wall thickness and that was it.
Caleb Lawson:
Yeah. Yeah, I just recently changed from a filament printer to a resin based printer. I got an Elegoo Saturn and I’ve been, I mean, super impressed with the results. My monitor actually is sitting on it stands and I confess this is a piece that I broke when trying to get it off the platform, but. you can see the print quality. I mean, this is just straight off the printer.
Jeff Girard:
Yeah,
Caleb Lawson:
a little wild.
Jeff Girard:
yeah.
Caleb Lawson:
So
Jeff Girard:
I have a filament
Caleb Lawson:
yeah, that’s crazy.
Jeff Girard:
printer, so I’m not gonna get that kind of quality, but.
Caleb Lawson:
Right, but you did get some really good quality for the knockouts of that table we did, well,
Jeff Girard:
I did.
Caleb Lawson:
the table I’m
Jeff Girard:
Yeah,
Caleb Lawson:
sitting
Jeff Girard:
and I
Caleb Lawson:
at.
Jeff Girard:
did
Caleb Lawson:
I
Jeff Girard:
nothing
Caleb Lawson:
know.
Jeff Girard:
to those. So I don’t anticipate doing having to do very much.
Caleb Lawson:
It’s very, very
Jeff Girard:
So,
Caleb Lawson:
impressive.
Jeff Girard:
pretty happy.
Caleb Lawson:
Yeah, love that.
Jeff Girard:
as a modeling
Caleb Lawson:
Before
Jeff Girard:
tool.
Caleb Lawson:
we… Yeah.
Jeff Girard:
So I was going
Caleb Lawson:
Well,
Jeff Girard:
to say,
Caleb Lawson:
and it, I mean, I’ve used to…
Jeff Girard:
as a tool for building parts for molds, because that’s what we did, use 3D prints as blockouts, custom-shaped blockouts for the big table that you’re sitting at. But just in general, it’s kind of a cool new tool in the toolbox.
Caleb Lawson:
Oh, for sure. I love using 3D printers. And I’ve got some parts and pieces I’ve made, like a camera holder for my phone. Because I don’t know if I’ve mentioned this on the podcast before, but my webcam on my computer got scratched by, I assume, a sand grain that I closed my computer on. So it works still, but it’s tragically bad. So I’m using my phone as a camera and so I’ve got a little mount, a little tiny mount that sits on my computer to hold it, which is
Jeff Girard:
Mm-hmm.
Caleb Lawson:
great. And then
Jeff Girard:
So
Caleb Lawson:
I’ve
Jeff Girard:
it’s basically
Caleb Lawson:
printed a
Jeff Girard:
a…
Caleb Lawson:
number of other phones.
Jeff Girard:
It’s an iPhone webcam.
Caleb Lawson:
Basically what? Yeah. It is. I mean, it’s like a ridiculously expensive webcam, but here we are.
Jeff Girard:
Yeah.
Caleb Lawson:
No, it works
Jeff Girard:
Here
Caleb Lawson:
great.
Jeff Girard:
we go.
Caleb Lawson:
Yeah. So before we jump in, a couple of things. So we announced publicly in an email blast, as well as I threw it into the big Facebook group, the Concrete Countertops Furniture and Artwork group. But I am now… jumped into CCI as a part owner. So we’re super excited about that.
Jeff Girard:
Caleb’s
Caleb Lawson:
So
Jeff Girard:
now
Caleb Lawson:
Jeff, you wanna
Jeff Girard:
official.
Caleb Lawson:
talk about that a little bit? I’m in it, I’m official.
Jeff Girard:
Yeah, sure. So, um, so Lane and I have owned CCI since the beginning, since 2004. And, uh, over the years she’s wanted to, you know, kind of get out of that and sort of retire and, and get her fingers out of running CCI, um, because it’s really my thing and, uh, so over the years we’ve we were kind of looking for somebody to kind of step into her shoes. And, uh, you know, many, many years ago when Caleb came to class, that was what? 10 years ago. Um, we saw some really good things and over the years we’ve started, you know, training with Caleb and, um, kind of getting to know him as a person, getting to know him as, as how he runs his business, how he runs his life and. You know, his personal qualities and his personal values are. you know, right in line with ours. And so the time was right. And, and Caleb’s now stepping into taking over all of Lane’s roles, um, as a, you know, marketer, promoter, uh, co-trainer. Um, we got some really good ideas, uh, about where we want to, where we want to go. I mean, CCI’s role has, is not changing. My role is not changing. Our vision for what we do and where this industry is going has not changed. CCI has always been and always will be about. high integrity, absolute honesty, and truth in the information we provide. And the information we provide is based on outside industry information from the engineering world, from the chemistry world, from physics. We don’t dabble in smoke and mirrors and… you know, emotional manipulation or anything like that. We are here to support you to make, to build your success. And we wanna be partners in your journey on that. And so Caleb has really shown his capabilities to do that. And I think this is gonna be a very, very positive thing for us. And so we want to welcome as many people as possible into our community. And it’s not a CCI community. This is the community, the concrete world. Because I know people, I have students all over the world and our visions for what we want to do, what we wanna create, our passions are all the same. And it’s not about making me feel bigger or more popular or whatever, it’s about you. And we’re here. Caleb and I are here to support you. Whether you have no interest in buying anything from us, if you just wanna talk to us, that’s what we’re here for. This podcast that we’ve started is here to just connect with you on a personal level so that you get to know us. It’s, you know, when you only are on an online forum or a Facebook group or something like that, the impression you have of people through text and through photos of their work is only a small fraction of who they really are as a person and who their business is. And this is another
Caleb Lawson:
Right.
Jeff Girard:
way that we can reach out and let you know who we are as people. Because when you sit across from somebody, and here you’re doing this virtually, if you were here watching this live, it’s live, you’re probably going to be watching this later on. through one of the streaming services, you get to know us as people, you get to see us. And although it’s not a true face-to-face, there’s something to be said about hearing somebody’s voice and seeing their face and matching their words to their actions. And so we want you to be comfortable with us as people and as leaders in this industry because the… All of us are going to fail if we try to do everything independently and are selfish about Only promoting ourselves, but we’re all going to succeed if we work together and share together and that’s what we are here for So
Caleb Lawson:
Yeah,
Jeff Girard:
everybody say
Caleb Lawson:
absolutely
Jeff Girard:
welcome to caleb
Caleb Lawson:
100%. Well, thank you, Jeff, for that. I appreciate that. Yeah, I mean, I again took the CCI ultimate course October of 2013. So this year, October will be 10 years since I took the class. Just had 11 years since I started my company. well, since I bought the company, I didn’t start it. I guess you could say I started my company in 2020 because I changed the name to Lawson Design in 2020. But yeah, I have been, I mean, as you may have seen, you may know like super, super passionate about CCI’s mission and the way that Jeff runs classes, the way that you teach. the basis from which you teach, I’ve always been very, very drawn to. As Jeff mentioned, we don’t teach from the… I mean, yes, there’s a lot of experience here, right? But I think, Jeff, you said to me the other day that experience… What was it? You really need experience after you, or before you gain it. It’s the wisdom that you gain
Jeff Girard:
I’ll be
Caleb Lawson:
from
Jeff Girard:
out
Caleb Lawson:
experience,
Jeff Girard:
of here.
Caleb Lawson:
you actually need that before you gain the experience. And so, I think that the bent of CCI to provide kind of the foundational experience, it’s always great to, that’s why. you learn from professors or you learn, you do a mentorship or you’ve got an apprenticeship. It’s like you’re trying to gain experience without going through the hardship of gaining experience
Jeff Girard:
Yeah.
Caleb Lawson:
the hard way.
Jeff Girard:
The quote, and this is
Caleb Lawson:
And so
Jeff Girard:
something
Caleb Lawson:
I’m
Jeff Girard:
I
Caleb Lawson:
really
Jeff Girard:
found on the-
Caleb Lawson:
excited.
Jeff Girard:
It’s some silly meme, it says, it’s a plane crash and it says, experiences something you don’t get until just after you need it. And that’s, you know, a little bit of a snarky,
Caleb Lawson:
That’s
Jeff Girard:
twisty
Caleb Lawson:
it.
Jeff Girard:
thing. But yeah, like if you’re gonna fly a plane, you go to flight school, right? You just don’t hop in a plane with your buddy and go, hey, let’s go. That’s
Caleb Lawson:
And it might
Jeff Girard:
cool
Caleb Lawson:
be
Jeff Girard:
if
Caleb Lawson:
the
Jeff Girard:
you’re
Caleb Lawson:
best
Jeff Girard:
gonna
Caleb Lawson:
plane
Jeff Girard:
ride
Caleb Lawson:
in
Jeff Girard:
a
Caleb Lawson:
the
Jeff Girard:
drone.
Caleb Lawson:
world, you know, Rolls Royce,
Jeff Girard:
Yeah.
Caleb Lawson:
whatever it is and all this, but,
Jeff Girard:
You know, that might be
Caleb Lawson:
but
Jeff Girard:
cool
Caleb Lawson:
I think
Jeff Girard:
for like,
Caleb Lawson:
that
Jeff Girard:
riding around in a go-kart in your backyard, but if you’re going to like do something serious, take, you know, learn from people who have
Caleb Lawson:
Take it
Jeff Girard:
the
Caleb Lawson:
serious.
Jeff Girard:
credentials, yeah, who are serious. So that’s, that’s where we’re coming from. Like that’s why I have all these things.
Caleb Lawson:
Yeah, I think that’s why I really, you know, my dad’s an attorney and
Jeff Girard:
Mm-hmm.
Caleb Lawson:
I’ve always gravitated very heavily towards the analytical, logistical, logical side of things. And so I think there’s a value in the emotional side of things. I mean, concrete as a material, as we as artisans know, is a super evocative thing. You
Jeff Girard:
Absolutely.
Caleb Lawson:
know, I think there’s… There’s a lot of emotion tied to the types of things, but the reality is it’s a medium. And what we want to help you do is to understand your medium and be kind of like, I’m gonna become an oil painter, but I don’t know the characteristics of oil paint. It takes a long, long time to dry and things of that nature. So, I think that is why I have so loved being a part of CCI from a kind of an ancillary point of view from assisting with classes at first. I think that was in 2018, I started doing that. And then I’ve done that, I did that a few times. And then in 2019, I hosted an alumni event at my studio, which led to hosting an ultimate class at my studio. And that kind of started the classes are held at Lawson Design
Jeff Girard:
Mm-hmm.
Caleb Lawson:
kind of thing. And so it was definitely an evolution. of roles and so I mean, it almost seems like this is the natural progression of the partnership to me.
Jeff Girard:
It is, yeah.
Caleb Lawson:
And I’m super, super excited. We have a lot of things kind of coming down the pipes that we’re stoked about. So be paying attention because there’s going to be a lot of really good stuff coming out that Jeff
Jeff Girard:
Yeah,
Caleb Lawson:
and I are really
Jeff Girard:
CCI
Caleb Lawson:
actively
Jeff Girard:
is not
Caleb Lawson:
working
Jeff Girard:
stagnant.
Caleb Lawson:
on. No, not at all. So yeah, I just wanted to jump in and kind of, you know, give that little update to the audience at large, if you will. It was funny. I just did that hand gesture, which was semi-Jazz Hands. And last week, Jay, my shop foreman, he saw me kind of editing the podcast and he was like, that’s your hook. You need to just have a GIF or a GIF of Caleb doing Jazz Hands.
Jeff Girard:
That’s hands.
Caleb Lawson:
So maybe that’s our new. I don’t know. But yeah, so those of you who are in the industry and have kind of been seeing me be a lot more active in the CCI kind of realm on the big Facebook group, on the CCI alumni Facebook group, that’s why. And so
Jeff Girard:
That’s why.
Caleb Lawson:
I want you to know that I’m available to chat, I’m available to talk to y’all and kind of be support, whether it’s technical or business. You know, really that’s something that CCI has always offered and I just, you know, my kind of personal aim is to kind of bring that out into the forefront.
Jeff Girard:
Yeah.
Caleb Lawson:
So
Jeff Girard:
So this is
Caleb Lawson:
yeah,
Jeff Girard:
all part of, you know,
Caleb Lawson:
with
Jeff Girard:
us getting
Caleb Lawson:
that.
Jeff Girard:
to know you and you getting to know us.
Caleb Lawson:
Yes, yes, absolutely. And so today, the title of our podcast is yet to be determined, but it’ll be something to do with exterior concrete, whether it’s countertops, fire features, water features, you know, whatever that might be. So Jeff and I really wanted to talk about the bones of outdoor concrete. So a couple of things I want to touch on before we get going. Jeff, so that we’ve got some outline points The benefits of a CSA-based cement in salty or chlorinated
Jeff Girard:
Mm-hmm.
Caleb Lawson:
environments, that’s huge. You
Jeff Girard:
Mm-hmm.
Caleb Lawson:
know, talking about certainly we’ve touched on sealer a number of times, curing, you know, just getting pieces outside that are going to last outside. Coming from Florida, I certainly did a ton of exterior concrete. And yeah, so I wanted to touch on a lot of those things. And then, you know, One thing that we have not done a ton of is talk about our products on the podcast. And while I do not want this to be an infomercial, that’s not, you know, I can’t stand infomercials. I’m not gonna be, who’s the guy that did OxyClean forever?
Jeff Girard:
Oh yeah,
Caleb Lawson:
Anyway, we don’t wanna
Jeff Girard:
really
Caleb Lawson:
do that.
Jeff Girard:
nice.
Caleb Lawson:
Huh?
Jeff Girard:
Yeah. Billy Mace, was
Caleb Lawson:
Memorable,
Jeff Girard:
that his name?
Caleb Lawson:
yes, Billy Mays. Memorable though he is, we wanna be a lot more personal than that. So I just posted on the CCI alumni Facebook group, if you’re a part of that, it was, I was like, all right, seal a discussion time. And the kind of rules that I put in place for that are, we’re not gonna bash people for what they use. So, we have expertise beyond our own products if you have a question or a technical issue with your products. reach out to us, I guarantee you we’ve probably tried it. So, yeah, so with that, let’s jump into concrete for outdoor kitchens and outdoor elements.
Jeff Girard:
So, you know,
Caleb Lawson:
So what do you think
Jeff Girard:
every
Caleb Lawson:
about that, Jess?
Jeff Girard:
time I start, I always have to start from the basics as a point of progression to give context as to where we’re gonna go. And when you think about it, almost all concrete in the world is exterior concrete. Sidewalks, roads, bridges, buildings, parking garages, that sort of thing, outdoor concrete. So we’re not gonna talk so much about that kind of concrete. where you really have to be sensitive about your cement content, how many sacks of cement are in your mix or errand training agents and things like that, because that kind of concrete, to be kind of blunt and judgmental, is ordinary plain Jane, okay, but not fantastic. The kind of concrete we work with and… There are a lot of people that use a lot of different mixes, but they’re all relatively similar in the sense that they have very, very great properties, especially if you’re using concrete that has polymer in it. You do not need, you don’t use air entraining agents. It’s not an issue. Even just high cement content mixes are very, very weather resistant, freeze-thaw resistant, that sort of thing. But… When we get down to the nitty gritty and start thinking about what kind of concrete we make and what are our customers needing out of our concrete? The preservation of that high surface quality, the integrity of the castings, the durability of the product over time from weathering and things like that. Those factors, that’s what we’re going to be talking about, right? Um, so one of the things you had mentioned, Caleb was, um, CSA cements and seawater. So anytime you’re near the ocean where you have seawater or salt spray, if you’ve noticed ordinary concrete tends to degrade, right? It gets, it crumbles, uh, spalls, looks nasty over time. And that’s because the sulfates, seawater has a lot of sulfates in it. And the sulfates attack. concrete. There are some natural ground deposits that have sulfate in them and that’s why there’s like a type 2 cement and a type, there’s actually a type 5 cement which you don’t normally, you can’t get, but like a type 2 cement is a moderate sulfate resistant cement that so if you were casting a footing in the ground and your ground has some sulfates in it and some parts of the country do and other parts of the world do too, you’d use a type 2. By and large, well, this is gray cement we’re talking about because there’s no such, as far as I know, there’s no such thing as a type two white cement. You just don’t do that, right? Why would you use white cement to floor footing in the ground? But all that being said is Portland cement, if it’s just a normal type one or GP or GU, general use or general purpose cement is susceptible to sulfate attack and seawater has a lot of sulfates as they said. So your concrete is gonna be more prone to that. Some pozzolans can help with that, help reduce that. So it is possible to make a more sulfate resistant concrete using the right cocktail of pozzolans and low water cement ratio and all that. But if you use CSA cement, like Rapidset CSA cement, which is the bellite form of it, that is very, very sulfate resistant because the basic chemistry is basically unaffected by sulfate attack. So it’s equivalent to like a type five cement. So if you are casting anything near the ocean, you might want to consider using that for long-term longevity. Now, sulfate resistance is not the same thing as acid resistance because there’s so many different kinds of acids that start to chemically degrade the concrete. We’re talking about something different. So this is a point I wanted
Caleb Lawson:
And
Jeff Girard:
to bring
Caleb Lawson:
now
Jeff Girard:
up
Caleb Lawson:
let me
Jeff Girard:
because…
Caleb Lawson:
interject your question on that, on the CSA and sulfates. Now, if I understand correctly, and do correct me if I’m wrong, it’s also resistant to a chlorine type attack as well. So the application I’m thinking of is like a, you know, chair or table in a pool or something, a pool
Jeff Girard:
Yeah,
Caleb Lawson:
bar kind of situation,
Jeff Girard:
um…
Caleb Lawson:
as well
Jeff Girard:
Possibly.
Caleb Lawson:
as being by the ocean. I mean, that’s, I wanted to talk.
Jeff Girard:
Yeah,
Caleb Lawson:
So I’m
Jeff Girard:
yeah,
Caleb Lawson:
just curious on
Jeff Girard:
um…
Caleb Lawson:
that if you know what
Jeff Girard:
most concrete, it’s not the concrete that chlorides affect so much as the, if you have steel reinforcing in it, that’s where the, that’s where the problem happens. Like steel, chloride intrusion in concrete is a bad thing because it really accelerates the corrosion of steel. Well, most of the time we don’t use any steel at all ever because we’re either using glass fibers
Caleb Lawson:
Yeah.
Jeff Girard:
or synthetic fibers or fiberglass or basalt rebar or some non-corroded corrosion-prone reinforcing material, that’s not super much of an issue. But yeah, who knows what else is in a swimming pool. So, and sealers,
Caleb Lawson:
But I still think those exterior
Jeff Girard:
yeah.
Caleb Lawson:
things, I think CSA is a really nice product.
Jeff Girard:
It’s a good, safe choice to use. And the fact that for a lot of us, it’s so readily available. Um, you go to Home Depot and you buy it. There you go. So it’s, you know, it’s, it’s not the only answer. It’s a very good, easy to get answer that also happens to be really easy to work with. It’s one of my favorite, you know, commercial bag mixes is, you know, when it’s 25 bucks for a 55 pound bag, you really can’t go wrong with that.
Caleb Lawson:
Yeah, yeah, and that’s gonna lead us down the road of a cost discussion here in a minute, I think. So let’s keep that in the back of our minds because I think that would be an important
Jeff Girard:
Yeah,
Caleb Lawson:
thing
Jeff Girard:
we
Caleb Lawson:
to discuss.
Jeff Girard:
can come back to that.
Caleb Lawson:
Yeah. So,
Jeff Girard:
So,
Caleb Lawson:
I’m going
Jeff Girard:
you
Caleb Lawson:
to
Jeff Girard:
know, I’d
Caleb Lawson:
see
Jeff Girard:
mentioned,
Caleb Lawson:
what…
Jeff Girard:
um, errand training agents and freeze thaw. So normally, you know, I’ll get, I’ll get questions from folks about, Oh, I live in Canada, it gets super cold, or I live in Minnesota and gets super cold. It’s not the temperature that matters so much as the transition from freezing to thawing. That’s the problem. So if your concrete only freezes once a year, okay. It only has to withstand. one freeze-thaw cycle. Well, like here in North Carolina, in the winter, we get lots of freeze-thaw cycles because it might freeze overnight and thaw in the day. So we might have 30, 40, 50 freeze-thaw cycles a year, which is a lot more stressful on concrete because it’s the expansion of the water. Not, you know, once water freezes, you know, that expansion’s
Caleb Lawson:
frozen.
Jeff Girard:
done. It’s already frozen. So it’s that change That’s the problem. And really high performance concrete, like what we make or what we should be making, um, is nothing’s immune to it, but it’s very, very resistant to it so much so that it’s not even something we have to think about. Um, so it’s, you know, if you come from the world of using conventional truck based mix where you do have to think about air entraining. once you step into this world and start using a different kind of concrete, it’s not an issue at all. So rest assured, really
Caleb Lawson:
Well,
Jeff Girard:
what we
Caleb Lawson:
I mean.
Jeff Girard:
have to all focus on, and I know you’re going to agree with me on this, is not the cold but the hot heat. That’s where a lot of the problems come from.
Caleb Lawson:
Yeah, so on the air entraining thing, what we’re really after is majorly mega-dense concrete. Because getting that air to “extrain”, if you will, getting that air out is so that kind of leads me to a really interesting thing that I kind of experimented with earlier this week. So as… Jeff obviously knows, and others know as well, I have been using our line of Alpha Pro products, the polymer, the fluidizer, plasticizer, and the defoamer, which I haven’t had as much of a need for the defoamer, honestly, because my concrete is not super foamy. There’s a kind of a misconception out there that all polymer creates foam, which is not true. And so anyway, I did a very interesting kind of case study in my shop last week. I cast six samples, three colors. So kind of an AB per color of those three colors. Two were CSA based and one was Portland based. And the test, the AB test was very simply alpha pro polymer in one and no polymer at all in the other. And I really ought to do a third test with Fortan just out of curiosity. But… What I kind of came out with, which was really interesting, was with the exact same in the CSA cement samples, the cement all, the results were both poured basically the same. They felt no different in casting. There’s no stickiness like you get with a liquid polymer. And these had no fibers in them. So that’s a totally different thing. But they both poured identically. They leveled out identically. The interesting thing was that the polymer sample was a little bit more color enhanced. So it was a little darker, a little more vibrant color-wise than the no polymer sample. And then the second thing that was very noticeable was the amount of pinholes in the no polymer sample. So the polymer sample had, I mean, 1% maybe of the pinholes that the no polymer sample had. We’re talking about a difference of night and day. And that was across the board. And then on the Portland sample, this was interesting. The polymer sample, polymer modified sample, I did not use enough fluidizer. I’m at a 0.29 water-cement ratio in Portland, a 0.35 in cemental, which is the minimum. And the Portland sample, I didn’t use enough fluidizer and I had to really manipulate it to get it to go into the form. I had to almost hand press it. It was a little more non-Newtonian than that, but not fluid at all. The not polymer modified sample, I added a little more fluidizer and it self-leveled. No problem. The interesting thing was when I flipped them the next day, there were zero pinholes in the polymer sample that I had to press in, and there were pinholes galore in the non-polymer sample I poured.
Jeff Girard:
Mm-hmm. Yeah.
Caleb Lawson:
And that’s been my experience with, since changing to Alpha Pro in general, is that I can direct cast backer, GFRC backer with 3% fibers, and have a virtually pinhole-free face.
Jeff Girard:
Yeah.
Caleb Lawson:
So that’s something that I’ve been really, really impressed by. And we talk a lot about surface quality and air entrainment. If you’ve got a lot of pinholes on your surface, there’s a lot of opportunities for stuff to get in and stain under your sealer.
Jeff Girard:
Yeah, yeah. Pinholes are, they are the chimneys that they are no different than like a deep scratch or a gouge or a chip. They’re conduits into your concrete and very, very few, well, no real sealers that perform well, other than like a thick bar top epoxy coating cover
Caleb Lawson:
bridge.
Jeff Girard:
tiny pinholes. Tiny, tiny ones. that you can barely see, those are the worst because, you know, the surface tension of the liquid holds it back from the pinhole. So little pinholes, some people call them pinners, are kind of the bane of our existence and they’re a challenge. So anything that you can do to make your concrete not have them is a good thing.
Caleb Lawson:
Yeah, so I mean, you know, I’ve gotten to the point now where I rarely grout unless the finish requires it. I mean, it’s wonderful.
Jeff Girard:
Right. I want to kind of step back and talk a little bit about polymer because, you know, you’re going to hear on online in groups and things like that, you know, some people swear at polymers, they vilify them, they’re like, oh, I don’t need them, you know, you don’t need them, or they’re bad for your concrete, or they weaken the concrete, or they slow things down, or whatever, right? And some of those characteristics are true, but they’re true for specific types of polymers. So it’s kind of like saying, like I’m gonna make a little analogy, way back when I first got started making concrete about 23 years ago and selling it. I had a husband and wife come in and my showroom was my kitchen. And we were talking about their project and they said, and I may have mentioned this story in the past, you know, they ask. We’ve read that concrete stains, right? So concrete, they’re lumping all concrete into one category and saying, all concrete stains, all concrete cracks, it’s all bad. And I said, that may be true for a specific piece of concrete made by a specific person, but mine doesn’t. So it’s different. And the same could be said for true polymers. Yeah, I mean, over on my… bookcase right there, I’m not going to get it because I have a dog on my lap right now and I don’t want to disturb him. It’s raining and he doesn’t like the rain. I have a book on polymers in concrete, right? There are lots and lots of polymers in concrete.
Caleb Lawson:
Thank
Jeff Girard:
There’s
Caleb Lawson:
you.
Jeff Girard:
not just, you know, SBRs and EVAs and acrylics and PV and all that, right? So there’s a lot of different kinds of polymer. GFRC and curing polymers are only acrylics. They’re one of the most expensive ones. And which is another reason why a lot of people don’t use them because they’re trying to be cheap and just save a penny by not using a good product to make their concrete better, which I
Caleb Lawson:
That’s
Jeff Girard:
think
Caleb Lawson:
going
Jeff Girard:
is.
Caleb Lawson:
to lead us right back to that same point of conversation here in a minute.
Jeff Girard:
Yeah, yeah. Pennywise and pond foolish, but we’ll, we’ll come back to that. So when GFRC became a commercial commercially viable product in the 70s, let’s say it was a spectrum of years, but let’s say it’s in the 70s, it was. Uh, a curing polymer that made it commercially viable because then you did not need to do a full seven day wet cure of your pieces before you then could install them and we’re talking like thousands of them. thousands and thousands of square feet of building panels all at once, right? So that’s, you need a big one, climate control warehouse, it gets very expensive. The role of polymer is to prevent, eliminate that from being needed. So you can cast today, de-mold, let it air cure, and it still will continue to gain strength because the polymer’s holding moisture in the concrete. That’s its role, that’s its job. And the only polymers at the time that were commercially available were liquid polymers. Fortan being one, PolyCure, PolyPlex. There’s three that I’ve used over there. PolyCure is up over in the UK. PolyPlex and Fortan here in the United States. Fortan’s elsewhere too. But these are all liquid polymers. So they are white high solids, usually around 50% solids. And… They all share similar characteristics. Their main job is to hold moisture in the concrete, and they do a really good job at that. But one of their side effects is they tend to make your concrete pretty foamy. And if you think about how commercial GFRC is made, it’s almost always pumped and sprayed through a big sprayer. And it’s the spraying action that purges a lot of that air. Well, if you take that machine away, And we’re not just talking about the miscoat, but you’re also spraying the backer too. So that action of spraying helps purge some of that entrapped air. Well, if you take that away and you are only pouring your concrete, there’s no action to get rid of that air. And because the polymer kind of creates a stable foam, even if you’re trying to vibrate the concrete, that foam doesn’t break up and let the air disperse. So these kind of polymers tend to make foamier concrete that if you’re not doing something to get rid of it, you tend to make less dense concrete. It’s physically less dense. And there’s a lot more entrapped air in it, which leads to slightly lower strengths. And…
Caleb Lawson:
And really that’s not about the lower strength of the physical material, it’s about the
Jeff Girard:
It’s the absolute material,
Caleb Lawson:
less material.
Jeff Girard:
the air. So if you, you know, you have a block of concrete and you measure it really carefully, and then you weigh it, you get a bulk density. And if you do that to different concrete samples, and we’re talking like measured to the thousandth of an inch. So you want to be really, you know, the, you need, you need good geometry and good, good measurements. And then you can get a pretty good accurate sense of the bulk density. And
Caleb Lawson:
What would be
Jeff Girard:
every
Caleb Lawson:
absolute
Jeff Girard:
time I do
Caleb Lawson:
zero
Jeff Girard:
it.
Caleb Lawson:
in the numbers? Like, you
Jeff Girard:
So like,
Caleb Lawson:
give me
Jeff Girard:
you’re
Caleb Lawson:
a number.
Jeff Girard:
going to hear numbers tossed around, which are based on different things. Like, so I’m talking in imperial units here. So normal concretes, typically the bulk density is considered to be 150 pounds of cubic foot. Well, that’s a rough average because a lot of it depends on the aggregates. And if you think about regular concrete, most of it is made up of rocks and sand, right? So if all your rocks are made and all your sand is made of quartz or silica-based minerals, they all have a specific gravity that’s about the same, which is pretty predictable, around 2.65, 2.6, 2.7, somewhere in that range. And then the bulk density of cement is known, the bulk density of water is known. So if you know all the bulk densities of all the ingredients and you know how much you’re using, you can calculate how much it should be, theoretically. But because when we mix concrete, we’re in an atmosphere, right? Air is always mixed into our concrete. We can never get all the air out. So the more air that’s in the concrete, the lighter it is, the fluffier it is. And the goal of all concrete, you know, if you are casting a wall and you put that vibration stringer down there, what you’re trying to do is not have honeycomb. You’re trying to work that air out, that big excess air out. So we want to fill as much concrete in our in our forms as possible because that’s where our strength’s coming from. And if you have an ingredient that creates foam that basically is dispersing that air into small tiny bubbles and trapping it, it can’t leave. So the more air that’s in your concrete, the lighter it weighs, but there’s less concrete there in that space. So it becomes weaker. Which is, here’s a tangential note. If you’re trying to make really, really lightweight concrete by putting foam into it, whether that’s styrofoam or pearlite or whatever, you’re just putting voids in the concrete and taking away the… you’re going to make weaker concrete. That’s just the nature of the beast. So that’s come back on this track. So when I developed Alpha a couple of years ago, I wanted a dry polymer. It’s not the only dry polymer. There’s other ones out there. But I wanted a dry polymer that was economically competitive with liquid polymers, but would give better performance. And it measurably does. So you don’t have to use an expensive liquid polymer that can’t let it freeze and things like that. And also have to struggle with it being sticky. And then you have to also struggle with it gets moldy or it gets chunky and stuff like that. And also they tend to make your concrete foamy, which you struggle with. And so that’s why a lot of people don’t use them because they’re, you know, you start to sacrifice the quality of your concrete because you’re trapped in this, using this material that in a way that was never intended to be. Again, commercial GFRC is sprayed. And if you’re not spraying it, you’re not making the concrete the way it was designed to. So with Alpha, you can get very, very high densities because it has, A, it’s not sticky. Like it’s an acrylic polymer, but it doesn’t have that sticky characteristic to it. And it has a very, very powerful defoamer in it built into it so that air comes out as you’re mixing it. It doesn’t create a foam. So you get much denser concrete, you get better surface quality. And so the characteristics you’re seeing, Caleb, of being able to direct cast and not have pinholes is absolutely
Caleb Lawson:
Consequently
Jeff Girard:
true.
Caleb Lawson:
also not have fiber showing, which is nice.
Jeff Girard:
Right, yeah. And they kind of go hand in hand in a way. So like, yes, I’ve been doing some tests with cementol, because there are a lot of people who use cementol and don’t use a polymer. They’re like, well, I don’t need it. OK, great. But I can make your cementol even better than what you’re making now. And so I’m doing flexural tests. In fact, this afternoon I have made some samples. and I’m gonna be comparing cement all same bag, same water cement ratio, same fiber content with alpha and without, and run them side by side. I already did it on some older cement all from a year and a half ago, and I got some interesting results. The results being the samples with alpha were 25% stronger the next day by just adding that. And you would think, oh, well, it’s going to make my concrete. No, it flowed better. It cast better. It tested stronger.
Caleb Lawson:
Yeah, I mean,
Jeff Girard:
And what
Caleb Lawson:
I know that there’s some pretty adamant voices against Polymer, which is interesting to me because it seems to me, and this is just me being a totally logical brain, but it seems to me that in an industry like PCI, they and their cohorts and the industry at large is doing billions of dollars of research to make sure that they’re… Because their bottom lines, I mean, when you’re doing a multimillion dollar project, your bottom line matters a lot, a penny matters a lot. And so they’re doing these flexural tests and these strength tests and these materials tests. And so if there was a better alternative to a polymer, they would have found it by now.
Jeff Girard:
Absolutely.
Caleb Lawson:
And maybe one day there will be some sort of synthetic alternative, I’m not sure. But you know. It seems to me that if that wasn’t the best way to achieve extremely high strength concrete, extremely resistant to, you know, I mean, your curing techniques are fast. So high strength, fast, economical, they would have found it and they would have done something different. And now that’s again, not to say that technologies don’t evolve, but we have not. gotten there yet.
Jeff Girard:
You know, it’s when you, when you have how many research institutes are there around the world,
Caleb Lawson:
What?
Jeff Girard:
hundreds, thousands of very smart people. And you look at what is there. message about curing concrete and the methods, especially when, you know, think about what we’re making. I’m going to grab a prop here.
Caleb Lawson:
Def Likes Propped.
Jeff Girard:
So I love my props, my little notepad. I got tons of these. We’re casting a countertop, a wall panel, a table, piece of furniture, whatever, right? We’re casting something, lots of surface area, not a lot of thickness. Like maybe you’re casting a wall panel that’s a half an inch thick, okay? But it’s several feet on a side. Lots of surface area, both top and bottom. for the moisture in that concrete to evaporate.
Caleb Lawson:
Bye!
Jeff Girard:
And if your concrete loses moisture, there’s a threshold below which it stops chemically reacting. So it’s not really gaining a ton of strength and certainly not giving you the strength you think you’re getting, or you’re being told you’re getting. The only way concrete gains strength is if it has the moisture, keep that reaction going. And curing the whole notion of curing, keeping it wet, keeping it covered, whatever, using curing polymers, its job is to hold up moisture in. It’s the moisture that’s doing the job. And
Caleb Lawson:
And now.
Jeff Girard:
when you make concrete, like, and this kind of blew my mind when I was younger in this, the first time somebody told me this, when you mix concrete and you put the water in the, in the mixer and you mix it up. That water is all the water that concrete will ever need forever. And all curing does is keep that in there. You don’t put water back in the concrete. If you’re having to put water back in your concrete after it’s hard, you did something wrong. It’s holding it in there. It’s keeping it in there. What were you going to say, Caleb?
Caleb Lawson:
Yeah, so curing practices, and I know that we’re on the topic of outdoor concrete, and I do want to get back to that, but this is very important, I think, to
Jeff Girard:
Yeah.
Caleb Lawson:
making high quality outdoor concrete. So your curing practices, is it enough? I think there’s a lot of maybe misunderstanding in the industry about curing practices, because we all cover our concrete. I use just plastic most of the time. I know you’ve been using some moving blankets lately. Others use heating blankets. Certainly in the winter, I keep my heat on, and that’s radiant. And so there are definitely, in addition to the covering it and things like that. So my question is, is plastic enough?
Jeff Girard:
So that’s a good
Caleb Lawson:
Without
Jeff Girard:
question.
Caleb Lawson:
polymer, I should say, really is the fact.
Jeff Girard:
Well, that’s that’s. Again, the role of polymer is to keep moisture in your concrete
Caleb Lawson:
Yes.
Jeff Girard:
forever. It doesn’t make it waterproof, it doesn’t make it stain proof, it doesn’t stop the water from evaporating. It slows it down.
Caleb Lawson:
And it also doesn’t make it take on the characteristics or properties of the polymer. That’s
Jeff Girard:
No,
Caleb Lawson:
something
Jeff Girard:
there’s
Caleb Lawson:
that
Jeff Girard:
not
Caleb Lawson:
I’ve
Jeff Girard:
enough
Caleb Lawson:
heard.
Jeff Girard:
in there.
Caleb Lawson:
Right.
Jeff Girard:
Sure, if you start adding a ton of polymer, it’s gonna make the concrete not rubbery. It never does that, but a little bit more flexible. But like with alpha, our solids dose, because since it’s a powder, it’s 100% solids, right? There’s no liquid. We’re only using a 3.5% dose. So four ton minimums, 5%. The commercial industry actually uses 6%. And then I’ve seen recommendations for 7% or more for certain applications. We don’t have to go there. We don’t need to be that high. We don’t need to like double the polymer just to get the kind of properties we want or what we’re getting. Um, but like when you said you cover your pieces overnight with plastic, I do too. That’s good practice. And the reason for that, the reason why you cover the, your freshly pieces of concrete with plastic is. It takes a while. It generally takes, I’m gonna wave my hands here, 16, 18, 20 hours for that polymer to fully coalesce and start to do its thing in your concrete, right? It’s not instant, it takes some time. So while that’s happening, your concrete is vulnerable to losing that precious moisture. And remember, your concrete is the most fragile, the most vulnerable, the most weak. right after casting. It’s like you just broke a bone, you got to let it heal. Well, if you broke a bone and put a cast on it, would you take the cast off the next day? No. And then start using it. No, you got to leave that cast on long enough for the bone to heal and then it’s strong. That’s kind of… That’s rough. That’s a weird analogy here. But like if you cast your concrete, and especially if you’re… foolish enough not to use polymer, and I’m getting on a soapbox here and being a little preachy
Caleb Lawson:
Preaching?
Jeff Girard:
here.
Caleb Lawson:
Ha ha ha.
Jeff Girard:
If you don’t use polymer and you don’t cover it in plastic, you’re an absolute fool because your concrete losing moisture, it’s not curing properly. You’re gonna have shrinkage issues, you’re gonna have cracking issues, and maybe it’s not right now, but down the line it will because you’re sacrificing the quality of your concrete. For what? a few pennies? Really? We want to make concrete that lasts a long time. My goal for all the customers I’ve ever had and for all my students who are my customers is I want you to have happy customers that you never hear from again. Because the only time you ever hear from customers, mostly, is when they complain about a problem. And that problem usually happens because you did something wrong. You created a situation that created a problem down the line. Now this is again kind of preachy, but this is what I’ve seen from near over 20 years of teaching people and helping people with troubles. Most troubles come from the manufacturer of the product or the choices that go into using too much water or the wrongness or whatever, right? Coming back down, the curing is a process of letting, creating conditions that allow the concrete, the chemical reaction, to continue so that you get to certain physical properties, strength, durability, low permeability, low porosity, stability, it doesn’t shrink and curl and things like that. You wanna get to that point. And if in conventional concrete, because you’re casting such a thick layer, it’s got a lot of internal moisture and we don’t really care too much about. the quality of the concrete. So, you know, we’ll strip the forms quickly and just let it sit out in the sun or whatever. Well, if you’re casting something thin, it’s gonna dry out really fast because there’s a lot of surface and not a lot of volume. So we have to really pay attention to maintaining those early days, that first, say, week, the first seven days are the critical to your concrete. Well, if I’ve got a curing polymer in there, all I need to do is cover it in plastic for one night, take it out. And now it can be in the open air, that polymer is doing its job. And it’s going to keep gaining strength and have properties that are so good at a week that I don’t have to think about anything. And you’re probably going to be sealing your concrete before then too. So that’s even better. Now, if you don’t cover it in plastic, it’s not going to start curing right because water is going to be evaporating real fast. before that polymer kicks in. And if you’ve noticed, you cover your piece in plastic overnight, you take the plastic off, what’s on the underside of the plastic?
Caleb Lawson:
water.
Jeff Girard:
Condensation, right? That condensation is the water that’s coming out of your concrete that would escape, but the plastics trapping it and at least creating a humid environment to minimize how much is coming out. One thing I have noticed since developing alpha and doing a lot of tests with it is, Samples that I cure under plastic have less condensation than samples that use Fortan.
Caleb Lawson:
noticed that as well.
Jeff Girard:
Have you noticed that too?
Caleb Lawson:
I
Jeff Girard:
That
Caleb Lawson:
have.
Jeff Girard:
means it’s doing its job even better than Fortan earlier,
Caleb Lawson:
Lower dose, mind you.
Jeff Girard:
at a lower dose, at a lower dose. So…
Caleb Lawson:
Okay, so that’s soapbox number one. And again, so, and one of the reasons that we’re talking about exterior concrete specifically is the environmental pressures for it to perform are so much higher. I mean,
Jeff Girard:
Yeah.
Caleb Lawson:
you know, a lot of like, I did, I mean, I did outdoor kitchens galore when I was in Florida. And I still do a fair amount of exterior stuff here. And, you know, the times that I would go and install something and It would get rained on the next day, or it wasn’t covered in indirect sunlight. I mean, I have clauses in my contract for, I don’t do dark colors in full exposure to the sun for safety reasons, really. But also, they’re more likely to have damage. And so these are the things you think about. But they are abused by just the factors of nature before you even use them. And so, especially in countertops, vertical surfaces not quite as much, but that’s one of the reasons we wanted to focus on. And really it’s best practices all the time, but they’re critically important when you’re doing exterior concrete. So, we want you to use the right ingredients. We want you to cure your pieces properly and treat them properly and then seal them properly. So I wanted to chat. really fast, Jeff, about the properties of a water-based, breathable urethane versus a non-breathable, solvent-based finish.
Jeff Girard:
Yeah. Or like a 100% solids epoxy. With outdoor concrete, most of us are in an environment where it rains and there’s humidity. You could be in the high desert somewhere where it’s 6% humidity. And that’s a slightly different story. But anywhere there’s lots of humidity. your concrete is going to, over the season, over the years, absorb some moisture from the environment. And In the sun, right, so we’re going to talk about, again, this is getting back to evaporation, okay? If you seal your concrete with a very impervious coating and, you know, gut, your gut is going to say, I want to protect my concrete, I’m going to use something that doesn’t let anything through, it’s bulletproof, right? Well, that works just fine indoors, but… You go outside and you put an impervious coating over something that’s got moisture in it. That sunlight is going to hit the concrete. It’s going to warm it up. And as you mentioned, you don’t make dark-colored concrete. Have you ever walked barefoot across a black parking lot, a blacktop parking lot?
Caleb Lawson:
It hurts.
Jeff Girard:
You’re going to burn your feet because it’s hot. dark colors absorb a lot of infrared light and get hot. Well, the hotter your concrete is, the more water vapor there is that is generated. So moisture in your concrete is turned into water vapor. Water vapor has a lot of pressure to it. And that vapor pressure wants to escape. You need that to go through your finish. That’s what’s meant by breathable. It’s not about air, it’s moisture vapor, it’s water vapor. You want that water vapor to expel itself through the finish. so that you don’t have problems. Now, this is well known in floors. Like if you go into a concrete floor and somebody comes in and puts an epoxy coating on a floor that’s moist or it has ground, it doesn’t have a vapor barrier underneath it and groundwater can get in there, you’ll get blistering. And that’s a big problem. And that’s indoor flooring. So if you’ve got a moisture vapor outside, you could have problems. And that… may not show up the first season, but if you’ve got that cyclical pulse of vapor pressure that happens every day, every night cycle, all summer long, eventually something’s going to give. And it’s either the sealer pops or flakes. It depends on the properties of that. It could delaminate. It’s like trying to push itself off the concrete because you’ve got, it’s like a balloon, pushing against that finish. And where is the concrete the hottest on the surface that’s sealed, that’s exposed to the sun? So if you’re using a finish that is not breathable, that doesn’t let water vapor through, you could be creating future problems that may not show up for a year or two or three years. And what does that translate to?
Caleb Lawson:
callbacks.
Jeff Girard:
A callback, callbacks. And those are super expensive. So. That’s why I said, I don’t want to hear from a customer because if I never hear from a customer for ever, 10 years later, 15 years later, and I have products out there that are 20 years old and I’ve never heard from a customer, that means I have 20 years of no callbacks. So I’m willing to spend a little bit more money upfront as insurance against future, very expensive headaches that come down the line.
Caleb Lawson:
Yeah,
Jeff Girard:
And that’s
Caleb Lawson:
absolutely.
Jeff Girard:
true of ingredients, true of Steelers, true of practices. Things like that.
Caleb Lawson:
Well, and I think having a reliable practice, reliable products, reliable sealers and things like that, that have been around long enough, which is hard in our industry because there are very few things that have been around a long, long time. And certainly there are new, with it being a young industry, there are new materials being developed all the time. And so that’s why we stress so heavily not trying things on your client’s work. Um, so I’m really adamant about testing a product separately and then adopting it as a user, you know, use case study. Um, because we don’t often have a lot of that data and I think that data is scoffed at a lot, it’s like, Oh, well, you know, I, I don’t know what the argument is against data. I really don’t understand that, but I think having
Jeff Girard:
Well, it’s not
Caleb Lawson:
it.
Jeff Girard:
opinion.
Caleb Lawson:
Exactly.
Jeff Girard:
It’s not
Caleb Lawson:
And
Jeff Girard:
opinion.
Caleb Lawson:
so, you know, whether it’s your sealer or your mix design or your, um, you know, best practices, like, make sure that those are viable and are working before you put them at a client’s home or project. Um, and, and that’s just, you know, it’s not me being preachy. I mean, it kind of preachy, but at the same time, it’s like, we’re trying to protect you, we’re trying to, you know, teach you how to swim, we’re trying to, you know, um, and rest assured I’ve made every one of those mistakes. So it’s not like I’m. you know, coming from some high horse and be like, oh, you never do this because I never did it. No, I did it. I did all of it. You know, and eventually, you know, I think people are like, well, this is impervious. It will come back to bite you. And so I think that’s why, you know, having the best practices and exercising the best practices often, evaluating them, making sure that you’re kind of is kind of in the right spot is prudent. Um.
Jeff Girard:
It’s good to innovate
Caleb Lawson:
Yeah.
Jeff Girard:
and it’s good to advance, but I keep one foot very firmly, not in the past, but
Caleb Lawson:
in the proven.
Jeff Girard:
on a foundation of solid proven knowledge that other people who are smarter than me have generated. And I am taking that vast universe of information. interpreting it through my training and my background and my skills to make it appropriate for what I know what our needs are. And that’s kind of the role of an expert is really a translator. And if you have so much hubris that you think you’re smarter than everybody else because you have an answer that nobody else has come up with. You either are a genius or you’re a fool. And unfortunately there was a recent incident, very tragic incident that the founder of this company ignored good industry practices and the advice of experts because he was smarter than everybody else and he had the answer that nobody else did and unfortunately. some terrible things happened because of it. That’s hubris. That’s foolish. And no, nothing bad is gonna, as bad as that is gonna happen with us. But we’re all in business. We’re all here to make a living, be creative, have happy customers. And there’s a simple recipe for doing that. And the simple recipe is, Trust, test, validate. and have confidence in what you’re doing. There was another, and I got distracted by myself and I forgot the other thing I was gonna say, but don’t make mistakes, don’t create problems. That’s how you’re successful. It sounds silly, it sounds very simple, and it sounds almost trite to say, oh yeah, everybody knows that, don’t. Don’t make mistakes, don’t create problems. But you would be surprised at, and everybody does this, how
Caleb Lawson:
Okay.
Jeff Girard:
many individual decisions you make, if you don’t think three, four steps ahead, what are the implications of that? One time I was putting a form together and I put the sync knockout in backwards. And I didn’t catch it until we de-molded. Had I done what I sh- teach people to do is say, okay, inspect your forms before you cast, because this is your last chance to catch a stupid mistake like that. I didn’t do that because, oh, well, I either forgot about it or I got distracted or whatever. I mean, that’s, that’s a process mistake, right? But that’s, that’s a good example of something simple you can do. That will save you money, save you time, save you headaches. And that never even got out of the shop because we corrected it.
Caleb Lawson:
Yep.
Jeff Girard:
But. I know, let’s say I go out there and I buy, I don’t know, I think I’m gonna be clever and I’m gonna go buy some new fangled whatever, sealer. Acme sealer that somebody is touting to be is the best thing in the world. And I don’t test it, I don’t validate it. I just go, oh, I like this guy. He’s good friends with me on Facebook and I’m. I’m all excited because he wears the same kind of hats I would do and we have tattoos and whatever. I’m going to do that too. And I do it on a big project. Maybe I get lucky with it this time, but maybe the next time the project’s a little different or something else is different that I didn’t pay attention to or I didn’t know was important because maybe the guy who is selling it to me doesn’t really know what’s important. He just wants to sell stuff. And I use it. And it comes back to bite me. And now I’ve got hundreds of square feet of concrete. I got to go back on a job site and spend days fixing. And now my reputation is affected and my customer’s mad. And maybe it’s going to cost me hundreds or thousands of dollars to fix this. And in all this process, all the projects that I had going on are on hold because I got to, I got to put out this fire and this fire was created because I didn’t do one thing. I didn’t test the finish. I didn’t validate it for myself. And that’s what we’re getting on about here. And as Caleb mentioned, we’re gonna come back to this, outdoor environments are extremely challenging. Just think about the temperature swings from winter to summer. You know, you could have a hundred,
Caleb Lawson:
day and
Jeff Girard:
a hundred,
Caleb Lawson:
night depending on where you
Jeff Girard:
day
Caleb Lawson:
are.
Jeff Girard:
and night, yeah. It’s huge. You’ve got sunlight exposure, you’ve got rain, you’ve got… birds and leaves and all kinds of things. And all of you folks who do decorative concrete, especially outdoor, you know what this is. You know the challenges. And one thing that’s gonna be true is there is no finish that’s permanent for outside. It doesn’t matter what it is, you’re gonna have to reseal. It’s just a matter of how often, right? So now part of that equation is how… easier, difficult is that going to be? And if you look at like in the decorative concrete world where let’s, let’s take like a stamp patio. Pretty common, right? Outside of our normal field of product, but a lot of folks do this. Um, the most common finish for that is a solvent based acrylic. Okay. Those are terrible for countertops, by the way, don’t, don’t ever use those for countertops, they just don’t perform well. Um, but they’re very, very good finishes for patio. And one of the main reasons is they’re kind of breathable and you can,
Caleb Lawson:
flash
Jeff Girard:
when
Caleb Lawson:
off
Jeff Girard:
you
Caleb Lawson:
fast, they’re easy to reapply.
Jeff Girard:
can put, recode them because they’re affected by solvents. So the solvent in the finish melts and dissolves the song, the finish that’s already there to kind of reemulsify it. Um, great for maintenance, right? So that’s, that’s where those products shine the right product for the right application. Um, I wouldn’t, like I said, don’t, don’t use like an epoxy, don’t use epoxy outside. Most epoxies will yellow and when, when an epoxy yellows from sunlight, from the ultraviolet light, it’s actually chemically burning. It’s like, like you put a slice of bread in, in a toaster, it’s toast. What you’re doing is controlling, you’re burning it in a controlled way. And, uh, well, that’s what’s happened with your epoxy. So any kind of finish or any kind of product you use outside. has to be used in stable, cannot be affected by sunlight. So use the wrong pigment, it could fade. Use the wrong polymer. There’s some liquid polymers out there that will turn yellow. They’re not curing polymers, they’re bonding agents. Totally
Caleb Lawson:
Yeah.
Jeff Girard:
different, typically SBRs or styrene butadiene rubbers, they will turn yellow in the sun. Don’t use them. And they’re not curing polymers, so don’t use
Caleb Lawson:
I think the bottom line that we’re kind of getting at here is that the, you know, using
Jeff Girard:
them.
Caleb Lawson:
exterior concrete is a similar but different animal. You know, you have to be more prepared for the types of challenges that exterior exposure
Jeff Girard:
Oop, you froze up on me.
Caleb Lawson:
– I didn’t in the recording, so, yeah.
Jeff Girard:
Okay, let’s.
Caleb Lawson:
You have to be prepared for the different types of exposure that exterior – you know, elements bring to the equation
Jeff Girard:
Absolutely.
Caleb Lawson:
long term too, you know, so keeping that water in your concrete and having a polymer is long term a good thing. You
Jeff Girard:
Mm-hmm.
Caleb Lawson:
know, so we don’t, you know, so all of that to say, I think that, you know, we’re just preaching about best practices, but they are particularly important outside.
Jeff Girard:
Yeah. Now, one thing that doesn’t have to do with an ingredient or anything like that, but a general characteristic of concrete in general, like if you are used to working inside a house. You kind of have it easy. And I’m talking mainly from a temperature standpoint here, you know, that the internal swing temperature of a house generally is pretty small. You know, for most people’s houses, it might be five or 10 degrees. We’re talking Fahrenheit, so centigrade would be like roughly half that. But let’s say it’s 20 degrees. That’s a lot for inside. But for concrete, that’s nothing. And what I’m getting at is the bulk expansion contraction from thermal changes. So if you’ve got a piece of concrete that is outside, let’s say you make a table and it’s outside, it’s just a slab. When it’s hot, it’s gonna get bigger. When it gets cold, it’s gonna shrink. And that’s just gonna happen. over the course of a day, over of course a few hours. If all of a sudden it’s, you know, beating sun and that, you know, now that piece of concrete’s out in the sun, it’s gonna get hot pretty fast. So the surface exposed to the sun gets hot the quickest and therefore expands the most. And the surface that’s in the shade or furthest away is gonna expand the least. or less quickly. So now you have a differential expansion rate, right? I’m getting to foam coring here. So in a lot of practices that people use is instead of casting a piece of concrete that’s say two or three inches thick, because they want it to be, look massive. They want the strength of a full bottom tensile face and full top face, but they don’t want a solid piece of concrete because it weighs too much and it uses too much material is they’ll embed a chunk of foam. So let’s say this is a piece of foam. You basically have a shell of concrete around it. And that shell of concrete’s usually half an inch or 13 millimeters thick or thicker. If you completely encapsulate a piece of foam with very dense, impervious concrete, you’ve just made a concrete balloon. And what happens to a balloon when you blow air into it? It expands. So if you’ve got a foam core piece of concrete and you put it outside and that top surface gets hot, two things are going to happen. That top layer is going to expand from the heat. Now foam is an insulating material. That’s why it’s used in insulation. So it is now a thermal barrier protecting that bottom layer, which is in the shade from getting hot. So now you have a situation where part of your concrete is expanding, part of it’s not. So it’s naturally trying to expand and it’s gonna curl. And then that top’s getting hot, but it’s also heating up foam is mostly air
Caleb Lawson:
Yep.
Jeff Girard:
and gases expand. when they get hot and a hot gas in a sealed environment is gonna create pressure. And that’s gonna start creating pressure and potentially cracking your concrete. So good practice is to drill vent holes on the underside that drill into the foam so that you alleviate that air pressure. Now
Caleb Lawson:
In
Jeff Girard:
good
Caleb Lawson:
fact,
Jeff Girard:
practice, excellent
Caleb Lawson:
anecdotally,
Jeff Girard:
practice is not to use any foam outside at all.
Caleb Lawson:
years
Jeff Girard:
That’s
Caleb Lawson:
ago
Jeff Girard:
the best
Caleb Lawson:
I used to
Jeff Girard:
practice.
Caleb Lawson:
use foam core a lot. And I did one outdoor thing and this was really, you know, I had started doing vent holes, but I hadn’t stopped foam coring, which I really have now. I don’t do a ton of foam coring anymore. But I didn’t, I forgot to drill the holes in the shop. And so I got to the job site and I installed the job. It was, you know, a hundred degrees outside because it was Florida in the summer. And tops were light, light gray, but they were really hot. And I was like, oh crud, I gotta drill a hole. So I went and got my tapcon bit, little, you know, they don’t need to be massive holes, small. And the first hole, I got through the concrete and I heard psst. I mean,
Jeff Girard:
Yeah, it’s like punching a hole in your tire.
Caleb Lawson:
yeah.
Jeff Girard:
It’s surprising how much pressure can build up. So there’s a tip for you guys. If you are going to foam core, make sure you have vent holes on the underside of your concrete. You know, obviously you don’t want them to be seen and they only have to be eighth of an inch, maybe quarter of an inch. Nothing big, but don’t just do one, do, you know, several to ventilate the pressure.
Caleb Lawson:
Oh, absolutely.
Jeff Girard:
So that was kind of like a side… side note on that. But the other thing I wanted to talk about was, okay, let’s say you’re doing an outdoor kitchen and it’s multiple pieces. So now you’ve got seams. Seams for outdoor concrete have to be treated differently than seams inside because of the expansion and contraction that occurs. And really what I’m getting at are two things, the size of the seam and what you put in it. Now, regular concrete, like a dry white concrete or whatever that has mostly rocks, has a thermal expansion coefficient. The rate at which it expands It’s just some number. I’m going to call it one, right? It’s some really small number. But what it means is you take the temperature of the concrete and the length of the piece of concrete. And that coefficient lets you predict how much that length is, how much that piece of concrete is going to grow or shrink. So if I, let’s say with, with GFRC, and these are really, really round numbers, right? I’m, I’m approximating. If I have a 10 foot piece of concrete and that 10 foot piece of GFRC changes temperature by a hundred degrees Fahrenheit, which is like between, uh, you know, winter and summer easily, that concrete is going to grow or shrink, depending which way you go by a 10th of an inch. That’s two and a half millimeters.
Caleb Lawson:
It’s almost
Jeff Girard:
So, oh,
Caleb Lawson:
in it.
Jeff Girard:
it’s almost, yeah. So it’s quite a bit, right? So if I have a 10-foot piece of concrete and I place it tightly between two other pieces of concrete, because that’s how I do it in a kitchen inside, and I install that, say, in the springtime when it’s room temperature out. Now in the summer when that sunlight comes on, so it’s dark concrete, that concrete gets hot, it jumps up potentially. I’ve measured concrete outside that’s a dark gray that’s 160 degrees Fahrenheit. That’s so that’s easy. So I could easily get a hundred, a hundred degree temperature change from when I installed it to peak summer temperatures. That concrete is now going to want to grow. and it’s going to be tight up against concrete. So it’s going to be fighting other concrete. Well, what’s happening to the material in between those, that seam, it’s getting squished. It’s getting crushed. And now it’s going to get squeezed out. Now go the other way. In the winter, it freezes, everything shrinks. And so it’s minus 20. Now that’s an 80 degree temperature change from when I installed it. So now that concrete is going to shrink by almost a 10th of an inch. And now that seam, which was height, expands.
Caleb Lawson:
So really,
Jeff Girard:
And
Caleb Lawson:
the
Jeff Girard:
that
Caleb Lawson:
good
Jeff Girard:
feeling.
Caleb Lawson:
rule of thumb should be a very stretchy seam material, silicone,
Jeff Girard:
Yeah,
Caleb Lawson:
something of that nature,
Jeff Girard:
and a big yeah
Caleb Lawson:
and a
Jeff Girard:
or
Caleb Lawson:
larger
Jeff Girard:
more.
Caleb Lawson:
seam. So an eighth of an inch seam in the summer would be ideal.
Jeff Girard:
Well, here’s how you’ve kind of figured that this is getting a little mathy here. You look at the expansion rate or the stretchability, the elastic range of your sealant. So silicone is, I think usually like 25 to 50%. Let’s just pretend it’s 25%.
Caleb Lawson:
There’s a company called Big Stretch that I really like. Their clock is very stretchy.
Jeff Girard:
Yeah. So there’s some stuff that’s got like 150%. So it’s very, very stretchy, right? So the more that product can stretch, the less problems you’re going to have. Now, so let’s work in really simple numbers here. If my seam will change by a tenth of an inch and my original gap, and my original seam was a tenth of an inch wide, and I could have a tenth of an inch change plus or minus, that means that seam can go to nothing or can go to 2 1⁰-inch wide, right? So I now have, and so I’m growing, that seam is growing, that original 1⁰-inch seam is going from zero to 2 1⁰-inch, that’s 100% change. So that sealant has to be able to withstand 100% stretch. But… Even if it could do that, you can’t have it go to nothing. So there has to be some allowance there. Now, if my original seam was two tenths of an inch and it only changed by a tenth of an inch, that’s 50%. See where that comes in? So really, really big pieces. going to change more than smaller pieces and larger gaps are going to change relative to their original length much smaller so your seaming material isn’t going to be affected. So it’s when you have a really big seam with really tight joints is where you’re going to have a problem. So you got to pay attention to that. And you know a good rule of thumb is maybe an eighth inch. I’d be more comfortable with three sixteenths of an inch and then using a very, very stretchy And then keeping those seams pretty small, you know, don’t do a 10-foot countertop. Yeah, the clients want it, but You’re gonna have seaming issues because that concrete is gonna move and the reason why GFRC and just it just as I’m talking about GFRC, but it’s nothing to do with the fibers. It’s the base concrete mix design
Caleb Lawson:
heavy
Jeff Girard:
So
Caleb Lawson:
cement.
Jeff Girard:
East NC UH PC all these are all under the same umbrella very high cement content mixes, where you have relatively small amounts of aggregate, aggregate expands and contracts a lot less than the cement paste. And when you have a lot of cement paste, the bulk matrix moves a lot more. So compared to regular concrete, like you pour a driveway, GFRC expands and contracts twice as much on average, twice as much. So it’s just stuff to keep it bare in mind. There’s some rough rules of thumb, but… Just bear that in mind, because if you don’t wanna have a callback, you can’t seem outdoor pizzas exactly the same way you seem indoor kitchens
Caleb Lawson:
Right.
Jeff Girard:
with the same ingredients. You have to change things up.
Caleb Lawson:
So that was an hour and 20 minutes. And I think that that’s a good stopping place because we’ve given people a lot to think about.
Jeff Girard:
Absolutely.
Caleb Lawson:
You know, we have, and so just for, and I’m gonna try and do chapters on YouTube, we’ll see. But you know, we’ve talked about, I mean, exterior countertops was the main focus, right? But we’ve talked about admixtures and polymer, you know, curing practices, foam coring, sealer
Jeff Girard:
breathable
Caleb Lawson:
selection.
Jeff Girard:
steelers.
Caleb Lawson:
Seeming for exterior applications, how to avoid callbacks in general for exterior
Jeff Girard:
the effect
Caleb Lawson:
applications.
Jeff Girard:
of color.
Caleb Lawson:
So
Jeff Girard:
or
Caleb Lawson:
this has
Jeff Girard:
dark.
Caleb Lawson:
been a very, very packed episode. So rewind, listen more, ask us questions. We’ve been receiving some comments on the YouTube channel, which has been fun. I would love to see some Q&A on the Spotify app. I monitor those, so if you’re asking questions, you’re gonna most likely get me answering, so that’s fun. And then reach out to us, info at concretecountertopinstitute.com with any questions. And again, plug, we’ve got classes coming up, August 7th through 11th. That one’s coming up real fast. We’re gonna be doing, I think, some real world application projects. So doing maybe a real project at my house. So… excited about that possibility. We’ve got a two day GFRC coming up November 9th and 10th as well as an ultimate course, five day ultimate course, Elevate Your Business in five days, December 4th through 8th, and then be on the lookout as well for 2024 dates coming up. So a ton to think about. a ton to listen through, a ton to absorb and assimilate. Join us also on Facebook, Concrete Countertop Institute, of course. And we’ve got a Facebook group that is CCI alumni that you can join once you’ve come to one of our classes, although I’m considering, maybe explaining that a little bit, maybe not, but we would love to see you on Facebook, Instagram, message us. And just be in touch with us, contact us, email, Instagram, Facebook, podcast, YouTube, et cetera, et cetera, et cetera. So we want to be accessible to you to help guide you toward true success in the industry.
Jeff Girard:
We’re here for you.
Caleb Lawson:
That’s
Jeff Girard:
So
Caleb Lawson:
exactly right.
Jeff Girard:
we wanna see you, we wanna hear from you. We wanna engage with you. So thanks for joining us today and we look forward to reading your comments and stay tuned till next week.
Caleb Lawson:
Stay tuned, have a good one.
Jeff Girard:
Bye bye.