EP #150: Most Concrete Floors Aren’t Flat Enough. Here’s Why.

Seth Tandett (00:00)
And welcome to another episode of the Concrete Logic Podcast. And today, I'm happy to have Chad White with SSI. He's back with us. You might remember him from episode 106, where we talked about best practices for placing and finishing concrete floors. Chad's been in the concrete industry for over 40 years. He started off as a cement mason apprentice to run in his own company. And now he's a senior concrete consultant with SSI.

He's worked on defined traffic super flats high tolerance random traffic floors suspended slabs and more he's a not ACI member and long time world of concrete speaker Today we're going to talk about the evolution of the means and methods behind producing super flat floors If you know We're going to revisit FFFL and FF men requirements. That's a lot of F's

Chad White (00:55)
Thank

Seth Tandett (00:56)
they're, they're, with all the automation that we're seeing these days, these, these requirements are getting tighter. so we're going to get into that today, but before we get started, just want to remind everyone how you can support the show. if you, if you go to, concrete logic podcast.com and there's a couple of things you can do for me. Well, I'll jump in ahead. First thing is if you enjoy this episode or any other of the episodes, you learn something.

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With that chat, let's get back into it. So we're going to talk about kind of the evolution of super flat floors. But I guess just to get you warmed up for today, let's talk about when you first got started. What was a high tolerance floor like back then?

Chad White (03:37)
gosh, you know, I started in the business in 1974. at that time, the only way we really tested floor flatness was the 10 foot straight edge. A class a finish was an eighth in 10, which basically meant when you set the straight edge down on the floor, if there was any gaps under the straight edge that was greater than an eight, that would not be a class eight floor.

And as if you start thinking it through, putting a straight edge on a slab in random locations is pretty subjective. So we really did not know what we were getting on the floor. And you got to remember, this was before laser screeds. This was before float pans. When we first started working on super flats,

We really had no idea what we were doing. it was almost like it was a magical thing. mean, how, how do we get these numbers? So with a lot of trial and error through the years, we came up with a system and really the first thing we start talking about super flats is, you know,

then that term is thrown around a lot in the industry. Yeah, we're doing super flat floor, this and that. But what's it actually mean? An actual super flat on an F-min, which is a defined path, is F-min 100. So technically, if you're doing an F-min 60, it's not a super flat. But we call them all super flats. And then on a random traffic floor, a

Superflat is considered anything that's an FF60, FL40 or above. Which with today's laser screens and pans and travel machines, just about everybody can pour superflat. So for the bait, what I consider a superflat for a random traffic would be when those numbers start getting up there. When we're talking an FF75, FL50.

That's a super flat because to me, the differentiator is when you're doing super flat, you have to do more work to that slab surface than you would do just placing a conventional slab. A little bit of the history on super flats. You know, they first came into being in the seventies and it was driven by narrow aisle high bay racking system.

And what they had the tow motor, the forklift, whatever you want to call it. They would cut a saw cut in the slab. would put a wire and that's what guides it. And then what brought about the tolerance issues was, you you've got warehousing racking that's now instead of the 35, 40 feet high.

you're going 60, 80, up to 100 feet tall. So think about it. If you've got a forklift that's got a footprint of six foot, it's booming up in the air 80 feet. If you're out a quarter inch, what's that doing to your mast up there? So if the floor is not flat enough, you're not going to be able to safely pick your stuff up there.

Seth Tandett (07:02)
been a long time since I've done trigonometry, but I don't know how far you'd be out.

Chad White (07:07)
You'd be out quite a bit, but,

so that that's what started driving it. And it was the just people, the warehousing logistics industry, they, needed to get flatter floors so they can go higher. And then on your, high tolerance, super flat random traffic. Initially about the only demand for it was like television studios or movie making.

to where they're rolling a camera along, well, if you've got a wavy or bumpy surface, you're going to see that in the filming that it's doing. So the first high tolerance super flats for random traffic were usually TV studios. But now we're seeing robotics. Robotics is pushing a lot of the high tolerance random traffic super flats.

because the robots have to travel everywhere in a random path. And if the floor's not flat, they have issues with, you know, maintaining their load and moving and everything. So that has become a lot of it. The other for random traffic that's would be ice rinks, roller skating rinks, gymnasium floors, stuff like that. Plus it's the nature of the beast.

You know, for years and years, a conventional slab of 3525 was about as good as we could do on a day to day basis. Well, as they've improved the laser screeds and the pan floats. Now my expectation, if I walk out onto a conventional job and they're using a laser screen and they're using pans, you know, you're going to hit a 6040. Just doing normal stuff, you know.

Seth Tandett (08:54)
And

how are we measuring that? Let's talk a little bit about how we're measuring these numbers that you're sharing.

Chad White (08:59)
Sure.

An F-min floor, which is what they call a defined traffic, that's measured with a profilograph. And what that does, that profilograph is set up where it's set up on the wheelbase of the truck motor that's going to be used. And then it rolls along on the...

truck motors are going to run on the same path all the time. They don't deviate at all. So they run this profilograph along, and it actually records exactly the waviness of the floor, what high, lows. And it's actually, it pops out a printed graph to where you can go back and you can exactly identify where you've got a high spot or a low spot.

and needs to be corrected. Unfortunately, that's always done after the work is done. So it's corrective grinding to get it in tolerance from that standpoint. But future, I think we're going to see some changes on that. Then on high tolerance random traffic slabs, they use a profiler. Your typical ones are a dipstick.

an axiom, a d meter, an f meter. And these are basically, they give you a point to point, let you know what the variation is over one foot. And as you know, an FL is your measurements over 10 foot, how much deviation, and your FF is over one foot, how much waviness. So you can have a floor that is

level but the surface is bumpy so the FL may be very high but the FF will be low. Then you can also have a floor that's tilted so it's not level but it can be perfectly flat so you could have very high FF numbers. So those are the tools that are used and a little history like say we started in the 70s

Seth Tandett (10:47)
Mm.

Chad White (11:07)
I'm looking at my notes here a little bit. The first, the F number system, which was developed by face companies, was first used in 1983. That was, that's, if you really think about it, it's not that long ago. We're, we're less than 50 years. Yeah. And,

Seth Tandett (11:23)
No, not at all. First, at least for some of us.

Chad White (11:29)
The ACI standardized F number system was officially, per ACI 317, was 1990. So we did not get rid of the 10-foot straight edge method, gap method, officially until 1990.

Seth Tandett (11:50)
I've had people on here on the podcast that wanted to bring the straight edge back.

Chad White (11:55)
Good Lord. don't know why. I mean, back when I was a, a, a finisher foreman working in the field, uh, you know, you could get with a client and they could go and check a floor and I'm good. I guarantee you, I can find a bad spot in any floor. You know, that will not make the eighth and 10, uh, actually to make a true eighth and 10, you're probably looking at F F numbers of.

Seth Tandett (11:58)
You

Chad White (12:23)
75 or 80 and FLs of 50 or above. Just a little history that my personal knowledge, I've went back and surveyed some. I went back when I was a contractor and I had 10 slabs that had tested all of them above an FF60 FL40. So I wanted to find out, okay, well how much, what's the envelope for that slab? And

We measured 10 slabs that we had done that we knew were 60-40 or above. And the average envelope was 3 quarters of an inch from the high to the low on that slab placement. So we're not as flat as we think we are. Laser scanning is beginning to show us a lot of that, that we're not as flat as we thought we were.

Seth Tandett (13:01)
Yeah.

Yeah, that's what I was going to ask you is, we getting better at measuring or are getting better at finishing?

Chad White (13:16)
Well, one, if we do one, the other follows. If we get better at measuring, the more data we have, the more we can improve. ⁓ Kind of getting off track here, but I read an article, there's a contractor in Japan and I don't have the article. I wish, cause I'd love to credit them. They were doing a ice skating racing oval and had to be extremely flat.

Seth Tandett (13:26)
Yeah.

Chad White (13:44)
They, combination of using a truss screed with laser sensors on it set up every two and half feet and real time laser scanning of the floor to where they literally had a projector mounted up on a crane to where they could scan that floor and then they would show in a different color anything that was out of tolerance.

Seth Tandett (14:10)
that's cool.

Chad White (14:11)
to where they could literally go out there and scrape it or fill it. They ended up doing that and they got that within two millimeters, the envelope on that slab.

Seth Tandett (14:21)
Wow.

It projected the color on there or did they look on a screen?

Chad White (14:26)
No, it projected the color on the slab. I'll send the article to you if I can find it. It was amazing. Now, what did it cost to do this? It was probably very expensive, but the capability is there. Yeah. ⁓ to where, you know, if you can get a slab two millimeters, the envelope from high to low, you know, that's just phenomenal to me. You know, she can do that, but

Seth Tandett (14:30)
⁓ yeah.

Yeah, somebody paid for it. Yeah.

Yeah.

Chad White (14:56)
Getting on the other things, the other high tolerance random traffic is your automated rack storage and retrieval systems that you're seeing being built now. And most of those, there is no forklifts running in the aisles. All the retrieving it's up on a, you know, runs right off the racking, but they want those floors to be as flat as they possibly can.

because they're maybe going 120 feet in the air and they don't want to shim anything, you know, or keep the shimming to a minimum because the more you have to shim racks, the less stable they are. So you're seeing a big push. Robotics is pushing more flatness in the floors and these automated storage and retrieval systems are requiring the floors to be much flatter.

Now talking about some of our legacy ways of how we did a superflat back in the day, which some of it hasn't changed a lot, but like, let me walk you through a typical F men in 1985. We knew we tried to, when I, that's when I worked, I worked with Baker at, at one time I worked with Jesco, I worked with Calvin, you know,

different people. But everyone's pretty much just saying the formwork you had to get the formwork exact because the only way that you could strike off the concrete was with a truss type screed which went from point to point. So even though your construction joints are under the racks and don't have to be flat you had to get them exact

so that the rest of your floor could be exact. So, and there was a lot of different things. People tried using a bar stock attached to a wood form and then you adjust it up and down and this and that. And it worked, but it was hard to keep it uniform over 300 feet or whatever. So we're really...

Seth Tandett (17:06)
Yeah, was there

a maximum width to your lane that you could do at a time?

Chad White (17:12)
Yeah,

typically at that time everything was one aisle. We did one aisle at a time. So in order to get under the racks, you were anywhere from 11 feet to 14 foot wide. So you you're pouring strips that are 200, 300 feet long and say, I would say if I had to be give you a typical, it'd be like 12 feet, 12 feet wide.

So you're setting up all these strips. And we would use wood forms. And this is when we first started beveling forms, to where you cut the top on an angle so that you're just finishing to a point. That's when we first started doing it. And we'd set up a jig, and you would always cut the grain. A piece of wood has a grain in it like this.

Well, you always wanted to tilt it to make certain that you're cutting the top of the grain so that the form would relax. So if you cut the other way, it's just going to warp. So we would cut all our forms on a jig. Then you would set them up, stake them securely, you know, at your joints on your form work. Then we would take a 12 foot straight edge and we would go down and at every joint in the forms

We would slide that across the top of it. Well, if it was high in any spot, that would leave a black mark. So then we would take a hand planer, you know, a power planer and literally plane the surface of it to try to get that form as level as we could all the way down. Very exacting, very exacting. Go ahead.

Seth Tandett (19:02)
So

can you compare that to what we do now? What do we do now?

Chad White (19:07)
biggest difference we're doing now is we've learned to use laser screeds to do super flats. So the screed because we're doing all this work on the forms, which doesn't mean we're only thing what's going to get measured is four foot wide in the middle of that 12 foot. But we had to have the forms perfect because of the way we had to strike it off. Now we're using laser screeds.

which is a wet screening process, doesn't matter what the forms are. So now when we go in to set up a F-min job, we'll use laser screeds on each side and it doesn't matter what the forms are. I mean, you still got to be within an eighth of an inch, but it doesn't have, it does not have, that has no bearing on what your tolerances are in your aisle.

So it saved a lot of work on the formwork, a lot of work. So now we got the forms all set. And there's various reinforcing systems. I'm not going to get into all that because we're just talking about means and methods here. But most of these slabs, F-min slabs, are not sawn. They're designed to crack wherever they'll crack. So they're heavily reinforced with either fibers.

or reinforcing or post tensioning. Back when we first started a lot of them were post tensioned. So you'll see various reinforcing strategies. But okay we got the form set. Now we're going to pour concrete.

And the difference with a super flat is you take everything one step further. Like when we're talking, when we're pouring conventional slabs, I like to see the slumps on the trucks. You know, no more from a truck to truck or over the course of the placement do I want to see more than a two inch variance. So if you're trying to pour it a five, you know, if you can keep everything between a four and a six,

You know, that's pretty good on a super flat. We were looking for one inch variance in slump. We, know, I don't want if we're trying to pour it a five. I'll pour six, but I'm not going to pour four right behind it. I might pour five. So every truck, we tried truck to truck to keep everything and you end up rejecting a lot of concrete and you end up, it slows you down. You're testing a lot more.

I've had a lot of super flats to where we first start pouring them worse. We're slumping every truck on a 300 and you're not pouring a thousand yards of super flat at a time. You know, you're pouring 250, 300 yards, but we're slumping every truck. And if it doesn't hit those parameters, we're rejecting it or tempering it or whatever. So productivity levels go down. need a lot more people.

The most common method back then and still is for doing narrow aisle placements is using a vibratory truss screed for your initial strike off. So we'd place our concrete, crank up the truss screed, and bring it down. And then while we're doing this, you've got two carpenters on each side.

checking the forms as the concrete is placed using wedges to make certain everything is dead on and we shoot everything with an optical. You don't use a laser with high tolerance. There's just too much variance in the band. So our recommendation is always use an optical, you know, builder's level to shoot everything in so you know exactly how much you're high or low.

And then after you strike it off, then we would use a typically a two by five, a big heavy magnesium or aluminum straight edge, longer than the width of the pour. And we would run that behind the truss screen and you used it in a seesawing motion to where you're sawing the top to where you're trying to get all of that excess off and get it down just

as tight as you can get it. Very labor intensive. And guys that did that on a regular basis had arms about like that, you know, from doing that all the time. So now you've got it, finally, you've got it struck off. Well, then you would start your bump cutting, which I bump cutter is basically that the simplest way it's a straight edge with a handle. Our bump cutters and check rods

They came from highway work originally. That's where your check rods, they would run those behind pavers. Why they were called a check rod and that a check rods when you lay the straight edge flat, a bump cutters when you raise it, put it up vertical. So like in the paving operation, they would run a check rod out and then pull it back and see if there's any highs or lows. Then you could use a bump cutter to scrape the floor.

Seth Tandett (24:11)
⁓ Okay.

Chad White (24:23)
So you would scrape the floor and that's a two man operation. One guy is pushing the bump cutter to straight edge out, which is basically a bull float handles and a hustler type head or, know, pushing it out. And then he would make his first cut to where he's holding it straight up or even cock backwards to where he's dragging that back. So that will show any low spots because you'll see the

light under it and any high spots you're going to cut them off which if it's too far out i mean you're going you're cutting into aggregate and as he pulls that to the side well that slurry that paste second guy has got a shovel and as he pushes it back out he throws that out to fill the low spots then you'll bring it over it again a typical super flat

you would bump cut it at least three times, oftentimes four or five. Once or twice before you started your float operations. And we always use walk-behinds. Back then we didn't have the nice double trowels like we do now. So we used walk-behind trowels with float shoes on them. And when you do your machining on an F-min floor, you don't, you know, it's typical.

to machine the first time in the opposite direction of the straight edge, and then each time you go in an opposite direction to keep it flat. Well, doing an F-min, you don't do that. You run everything long ways. You don't cross anything up. Because I don't care if the whole slab's flat. I just want that aisle where those wheel tracks are. That's what has to be flat.

So I'm machining everything in one direction all the time. And that goes from my floating operations to my troweling operations all the way through. I never turn the machine the other direction. Everything runs to one direction. And then what we would do after we had pan floated, we would take a straight edge. straight edges are hollow. I don't know if you know that. They got end caps in them.

Seth Tandett (26:41)
Mm-hmm.

Chad White (26:42)
Well, we would take four or five number five rebar, put them inside the straight edge where that straight edge weighed about 50 pounds. And that would be our last pass over. The floor would be with a bump cutter, a 50 pound bump cutter, pulling it across to scrape that last little bit. Then we would finish it like you would finish a normal slab. you want a semi glossy hard trowel finish?

So now you're done. So then they come in and testing agency with your profilograph, which is set up. It's got wheels on it. It's set in the exact way the truck motor it is. They'll set a string line to where it shows the center of the aisle. They position the machine. Then they'll run the machine down to test you. And as they're running the test, like say it's got a little graph that's actually printing out.

They'll make the run, pull it through, and they've got a band on there of what. So everything ideally stays within that band. Anything that's out of the band has to be corrected. And typically on an FMIN job, you're allowed corrective grinding for 5 % of the aisle length. So if you poured 100 foot of aisle, you can correctively grind.

five foot of the aisle and still be within specification. We always shot for three percent ourselves and yes can you do a an f-min 100 super flat and no grind? Yes it happens but I don't know of any job where they've done multiple pours or placements where they did not do any grinding.

The best floors I've ever done, we had to do some corrective grinding on. So then, like I say, he's got the graph, he's identified the areas, then they'll go back and mark them. You know, between this point and this point, you know, you're out three mils, you're out six mils or whatever. And then you're allowed to correctively grind in that area to get your floor.

Seth Tandett (28:34)
Mm-hmm.

Chad White (28:59)
And the biggest problem with super flats is the same with all concrete, just because you measured it and ground it on day one through day seven. There's no guarantee at day 365 that that floor is still the same. You know, the floor moves, it curls. So that's where your different reinforcing strategies came in, you know, to try to mitigate the shrinkage and curl on a slab. But

Seth Tandett (29:15)
Yeah.

Chad White (29:28)
Unfortunately, we haven't been able to get through that all the way.

Seth Tandett (29:33)
What time frame do you usually see where you do a corrective action like a grind?

Chad White (29:37)
Typically when you're doing this, you want to do the grinding before the slabs cured, before it slabs too damn hard. And cause that's about all you can ask of a concrete contractor. I put it in per your specifications, you know, what it is six months from now, that's something else that's going to be dealt with. I can't control that part of it, you know? So yeah. And

That's why you're seeing a lot today. There's a lot of, you know, our in the United States, everything is spec warehousing. So they may have a warehouse that, you know, is built to 50, 35 standards, then they want to come in and do a narrow aisle high bay thing. So they'll come in and do corrective grinding over the whole floor, every aisle, you know, so that can get very expensive.

Then, when it came to high tolerance random traffic floors,

Initially, when we first started out, we kept the placements very narrow. Anything that you could reach from one side or the other with your bump cutters, that was the limiting factor. So you very seldom got over a half a bay wide because you could not reach it with a manual bump cutter and do it effectively without getting out on the floor.

What we would do is, you know, the same tolerances on slump temperature set. And then we would extensively bump, you know, uh, at the beginning, you know, we were still using truss screeds. Laser screeds didn't really come around to like 1986, I think 85, 86. I actually looked it up as to when, I think, uh, 86. Yeah.

⁓ So before that we were using truss screeds. Then we would just bump cut it, bump cut it, bump cut it, and that's where we was at. So super flats are very labor intensive, even to this day. It's not as much as it was, but they're still very labor intensive. And you still have the conundrum that, you know, we're going to place it

Seth Tandett (31:29)
Okay.

Chad White (31:52)
to these specifications today, but six months from now it may not be there. But this is the best we can do right now.

Try and think.

That was really about it back in the day. Now though, we're seeing some innovation in the market and

The biggest things, the two biggest innovations that have probably increased our ability to get flat floors. Number one is the laser screen. When they came out in 86, that opened up to where now we could do high tolerance random traffic slabs that were 50 feet wide, that were a hundred feet wide, that were 150 feet wide. Because

You know, it was all wet screening and are the initial laser screeds that came out. were good, but they were nothing like they are now. Uh, back in the day and I, it makes me sound old when I say back in the day, but, uh, when the laser screens first came out, we could hit the 50 35 numbers pretty consistently, but we had to bump cut it one time. Now.

You know, as I said earlier, my expectation is a 60-40 and not doing anything other than normal conventional finishing. And the big difference is the laser screeds. Laser screeds have gotten so much better. The hydraulics, the laser systems, they can really get you a flat floor. And the second innovation that has really changed our industry is

float pans. And I believe Allen Engineering was the originator of the float pans. And that was in 1989. So it hasn't been that's 35 years ago. But that increased our FF numbers from using float shoes tremendously, tremendously. So those are the two big things that have changed how we approach

high tolerance, super flat floors. And then since that time, we've had a couple other things that are coming on the market that have really helped the bump cutting. Like I said, manual bump cutting is very labor intensive. There's a safety issue to it. There's a lot of back strains, a lot of hemorrhoids, because you're pulling.

Jerking and it's it's bad on your body. It's just bad on your body. So over the last 15-20 years people have experimented with different bump cutting attachments that are either mounted on a troweling machine or pulled behind a troweling machine and we've got that they've improved that quite a bit to where you know, you've got

We can now probably using a bump cutter attachment on a pan machine, we can increase the FF numbers probably about 20, 25%. Yeah, it's caveman technology. It's doing the same thing as a manual bump cutter. But where I was talking earlier that maybe we would bump cut

Seth Tandett (35:10)
wow. Just dragging dragging it behind the machine.

Chad White (35:24)
manually three times, very labor intensive. Now using a screed sled, a bump cutter attachment behind your trowel machine, you're bump cutting the floor 10, 15 times. know, machine don't get tired, you know, unless it runs out of fuel, it'll keep going. So that's really improved that aspect of it. ⁓ Another thing we're seeing is

Seth Tandett (35:48)
Yeah.

Chad White (35:51)
Flat pan, we're seeing dedicated panning machines. You're seeing several of the large manufacturers have come out with dedicated pan machines. And then you also see an aftermarket where you can change the arms out to where they spread the weight of the trowel machine more equally on the float pans. So you have

greater contact with the floor with the float plan. So we're getting flatter floors using those systems. I think, and don't quote me on it, but I think they say a typical pan with the trowel arms, you've got about a 40 % contact with the slab surface of the pan to where when you use all the one I can think of offhand is the Bigfoot

pan saver system. They spread that out and they say they're getting about 70 % contact. So the more contact you get, the flatter the floor is.

Laser screeds, we've learned to use them much better. We've found that you, we had talked earlier about we would strike it off with a truss screed and then run the seesaw behind it. Now what I'm seeing when we do super flats, we will double strike or even strike the slab three times with the laser screed head to get the floor flatter. And we've also learned

The big thing on the F-MENs that's really done some cost saving and allow us to make larger placements is we're using two laser screeds, one on each side of the pour, and they're booming out. Like say, we're pouring an F-MEN, we're not talking earlier, 12 to 15 feet. Now we're pouring up to 35 feet wide and we're pouring

two to four aisles at a time. Using the screed on each side, they're booming out to the center and screeding the slab back on each side. And we'll have them screed it three times.

Seth Tandett (37:58)
Yeah.

Chad White (38:03)
They'll go back, screed it, screed it again. What I always like, I like to see them. What I tell them is, you know, the auger on a laser screed is what is doing your strike off. So I tell the guys when I'm training and working with them that I want you to screed that floor to where I see nothing coming off that auger. You know, I don't want anything coming off of it. We've got that floor as flat as we can now.

And with the better laser screens, the better hydraulics we have now, we're getting some really good numbers. And now the edge forms, it doesn't matter, you know, because they're not dictating the elevation of the floor. So we don't have to be as critical, don't have to spend as much time on the form work. So there's a cost savings there. Plus we can go wider. So that has been a huge benefit.

Seth Tandett (38:58)
What about design as far as the concrete itself? Are we getting better at that? Is that making it easier as well?

Chad White (39:06)
Well, concrete has always been a compromise. It can do a lot of different things. if you do this, to bump cut a floor as much as the straightening and restraightening of a slab surface, you've got to have paste. So how do you get paste? You've got to have cement.

So you raise the cement. So what happens when you raise the cement? You've increased the shrinkage potential of the floor. You've increased the possibilities of delamination or peeling or whatever. So you have to design a mix that how it's kind of, you don't make everybody happy. You don't hit all of them, but you try to do the best you can. So, you you got to have enough pace.

where you can finish the floor after you've scraped it numerous times, you've got to have bleed water. You've got to, you know, as an old finisher, know, back in the day, we fought excessive bleed water. And most of that was because we had gap graded aggregates in our concrete. So you had all the channels for the water to go up. Now,

We've optimized the aggregates so much better where we've got a much more cohesive blend of concrete, but it comes down to, it's not exotic mix designs. It's the discipline to execute the same truck to truck to truck to truck, you know, getting the slump that the biggest thing is

Seth Tandett (40:40)
Yeah.

Chad White (40:46)
probably is the consistency of the slump and the rate of placement. Because every time I've seen grinding on a typical high tolerance floor, it's where you start and stop. It's off where you started this pour. And if you had to stop for some reason and start again, and then when you got to the end of the pour. If I had to pick some place to where, yeah, that's where you're going to have issues, those are where they're at.

So you want to make a factory job out of it. It's very difficult to do high tolerance floors outside unprotected in the elements. It can be done, and it is done on a daily basis, but it's difficult. As I've said on any concrete, you want to control the variables and eliminate as many of them as you can. So ideally, when you're doing high tolerance floors,

You want a controlled environment. You want the same weather every day. You want the same concrete every day. You want the same temperatures. You don't want variation. That way you can figure out what works. And you can do it consistently, repeatably every day. So it's the execution. it's, I've said it a thousand times, it's.

Seth Tandett (42:02)
Yeah.

Chad White (42:09)
attention to detail. Well, the details matter a lot more on a high tolerance slab. ⁓ Going forward, the future, I think what you're going to see is

Seth Tandett (42:15)
Mm-hmm.

Chad White (42:23)
laser scanning. We're going to have the more data and information you can furnish in real time, the better job you can do. And our ability to collect data is improving all the time. Laser scanning, you know, we're starting to see some of it. You know,

They'll come out and they'll laser scan while you're poor. And part of the problem is you can only do sections at a time, but we're going to get past that in some way, to where you're going to be able to give information to those crew leaders on the job. Hey, we're out of tolerance right there. And they can fix it in real time versus doing it, grinding it after the fact. So I think.

Seth Tandett (43:06)
Mm-hmm.

Chad White (43:14)
Going forward, I can't think of any new or exotic technology that's on the horizon that's going to dramatically change how we do high tolerance floors. But I do think our ability to gather data in real time is what's going to push us forward. So you're going to be able to

If they can get data to you to where you can make corrections. Now we're not confined by configurations of narrow aisles. You know, we can make placements of various configurations and still get the same flatness. So and I think that's what we're seeing coming in the future. So and that's pretty much where we're at right now with high tolerance floors of the F men.

Define path, that's always gonna be a little bit of a niche market, but the high tolerance random traffic floors, we're gonna see an explosion in that. And robotics and the automated rack storage system is what's driving that. Plus we have the ability to do it without a tremendous additional cost. People are always gonna want flatter floors.

Seth Tandett (44:20)
Yeah.

Chad White (44:28)
The flatter the floor is, the easier it is to work off of it. ⁓

Seth Tandett (44:34)
Yeah, it gives

the building more versatility in what it can be.

Chad White (44:39)
Exactly, okay,

any other questions on?

Seth Tandett (44:43)
No, I mean, I think you covered everything that we were thinking we were going to cover today. ⁓ So I appreciate it. Always glad to have you on the show. If folks want to reach out to you or SSI, what's the best way?

Chad White (44:48)
Okay.

Probably the best way is either at our website SSI.com or I can be reached at cwhite at SSI team.com and yeah give us a call we'd be happy to talk to you.

Seth Tandett (45:13)
Yeah, and we'll have Chad's link in the show notes so you know how to get a hold of them. And if you he'll have his own. He already has his own page since he's been on the podcast before. But if you go to the podcast website, Chad's got his own page so you can go and find his link there as well. All right, Chad, I appreciate you coming on the show today. Glad to catch up with you. Yes, sir.

Chad White (45:33)
Thank you. Great.

Seth Tandett (45:36)
And folks, until next time, let's keep it concrete.