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Common Retaining wall mistakes & how to AVOID THEM, bad designs, bad base, wrong block....#2

 

Stan: Man, I'm seeing stuff for the first time that I've never seen before. 

Stan: All right, well welcome back guys. Today, we got a pretty packed show for you because we are going to walk you step by step how to base your own retaining wall block. We're gonna take all the mystery out of what you do, why you do it, and how you do it. So get ready for that. Plus, we're gonna talk in detail about why some landscaping companies like to offer "tiered retaining walls." Now I'm air quoting for a very specific reason, because there's kind of a few red flags, I guess would be the way I'd say. If a landscape company is only offering you a tiered retaining wall, there's a reason, and we want to make sure that you guys fully understand all the benefits, and all of the bad things that go along with building a tiered retaining wall.Plus then today, we're gonna talk in depth about why these systems are mortarless. It's crazy, but there's a rhyme and a reason to that as well. So without wasting anymore time, let's start building some retaining walls.  Find my box. I still haven't put the collar on my box from the last video. Are we rolling?

Speaker 2: Yep.

Stan: All right, so we are four feet in the air. We're four feet up on this retaining wall and we're talking about base because it all starts right here. A piece of equipment like this is absolutely fundamental to making sure that your base is done the right way because no matter what you do when you go to dig out that bottom of that retaining wall, when you hit that raw soil, you're going to loosen it up. So before you do anything else, before you put in your base material, before you do anything, you take that raw soil and you compact it. A packer like this will pack down approximately eight to 12 inches, so if you happen to make a mistake and dig deeper in a spot than eight to 12 inches, then you'll have to compact in lifts. And a lift basically means that you put in eight to 12 inches of material, compact that, and then come up the rest of your height and pack it. If you put in two or three feet of soil all at once, this thing won't compact it. It'll pack the top, but it won't leave anything down below compacted and it'll leave it soft. 

Stan: So let's go actually over to the base, and we're gonna show you what we do. Actually, you know what? Before we go to our actual base, here we go. This is great. Right here, this is actually class five material. This is recycled class five, and a lot of guys use this for their base because it's inexpensive. I don't prefer to use this for the base because it's more difficult to work with. So I wanna actually demonstrate something here real quick. When we go to lay a block, we have to get this block perfectly level. We should probably base a block. I'm thinking we need to base block. Do we got our basing material, our level here, Blane? Thank you. 

Speaker 2: Stan, you're not supposed to base blocks between the walls. You're supposed to base them on the wall. 

Stan: Okay, Elliot, I mean Zander. All right. So the reason I don't prefer class five is it doesn't have any give. Once it's compacted, you can't change anything. So the material that I use as the 3/4" clear because there is enough give, but once it's locked in place, it's solid. But let me show you some of the criteria we use for basing a block. So this block is obviously not, wow, that's actually pretty damn close. All right, come on over here and check this out. So when we base a block, you've gotta have your bubble perfectly in the middle under most situations. Now it's okay, now in this case, if you look, the bubble leans towards the front. That's actually okay, guys. This is kind of odd that this block is actually that perfectly level, or I'm just that damn good, which I'm actually not. So a little bit of the bubble leaning toward the front means that the block, if this is the base of the block, leans just slightly, just a titch, inward. And the reason you want it to lay a titch inward is to compensate for the geo grid that goes in the backside of this block. 

Stan: So as you lay the geo grid fabric right here, what happens is that typically tends to lift up the next course, kicks the tail end over. So if you've got a four or an eight foot tall wall and you've got multiple layers of geo grid in there, you need to compensate at the bottom for how much of a forward elevation that geo grid's going to give it. Now as you lay this block down, this one's gonna be off. Okay, so come here. We're perfectly level this way, but now side to side, this is where a lot of guys go wrong. You can see how far this is off. This block needs to come up. This side needs to come up this much to get to level. To do that, this is an eight pound dead blow hammer. Is this an eight pound, Blane? I think he went to the gas station. See what happens? 

Speaker 2: Yeah, there he is, right there.

Stan: There he is. There's Blane. It's an eight pound. All right, so to do it, here's the thing. You can't use a steel mallet on this because if I hit this block with a steel mallet, I would tend to bust this block up pretty darn quick. If you don't have a dead blow hammer, which these cost about 70 bucks, you can use a piece of wood and a framing hammer. Put a big old 2x4 right here, and then you hit the 2x4 on top of the block, and that'll get it level. But really what you're trying to do is you're trying to beat this down to the right elevation. And you can see the challenge that I'm facing already. I can't get anywhere basing this block on class five. So if we were gonna go base this same block down in the trench on 3/4" clear to clear, you're gonna see how much easier it is. Let's do that now. I'm not trying to sell you guys, is it rolling?

Speaker 2: Yeah. 

Stan: I'm not trying to sell you guys on these blocks, but a lot of you guys have asked what this is. This is called actually a VERSA-lifter, and it just creates a handle for the block. Do we need to actually go any further with this wall, Blane?

Blane: We're going up from there. We're stepping up there. 

Stan: Stepping up? Okay, so I just wanna demonstrate to these guys how we base a wall. All right. So as we get down into the trench, thanks Blane. So as we get down into the trench, technically this wall gets stepped up, but I just wanna demonstrate how we base the block. Actually, this is gonna throw it off. You can see where this grid would throw it off. But anyway, we lay the block in. Now, I'm not gonna go through the whole process of basing this block because you guys would get bored, but side to side, we're gonna be level. And then we're actually going to level it to the block next to it. Once we're level, this block is perfectly level with this block in both the front and the back, and it's level front to back this way, we're good to go onto the next course. Maybe I should just do it. These guys are gonna wanna see it. 

Speaker 2: You've gotta give the people what they need, Stan. 

Stan: Well, these guys are gonna wanna see it. This is gonna help these guys figure out how to do it on their own job site. Just talking about it doesn't do it. Sometimes they just need to see it. All right. Okay, so what you guys see me doing is I'm digging this out. That's another reason why I like this 3/4" clear because I can dig this out like this, and if this was class five, this would be pretty tough to do, but because it's this material, I'm not worried about loosening this up because it's locked. It's locked into place, it's not going to move. So there is a rhyme and a reason why we use this. 

Stan: Okay, flip this back. We typically wouldn't have geo grid in place already. Gonna clean this block up. We don't want any rocks whatsoever on the surface. Now this block now is too low. This side is high, we look at the level. This side is kicked up, so this side needs to come down, this side needs to go up. We also gotta level it here. You can see where I'm hitting right here, meaning my whole block is just a titch low where it marries up to the next block. So let's actually raise this up. It won't hurt if we bury an extra block down here anyway. Okay. So now the block is pretty level, but now we're just a titch high, actually. It's gonna be almost impossible for you guys to see, but this block is just a touch too high, and my level's saying that I'm going up at this angle. We're definitely too high right here. So you can see where we're floating above. Now the easiest way for me to do this is not to remove materials, but for me to settle this block into place. 

Stan: Now I've got solid contact with this block in the front. I've got solid contact, nope, doesn't take a whole lot, especially with this material. I'm perfectly level side to side. Come here, you see this? Pretty much level, but it's not perfect. Luckily, this block is not needed, but we might as well do this the right way. At this point in the game, guys, this is gonna seem tedious, but if you rush this part, your whole entire wall for the entire length of time you own it is gonna be screwed up. This is the part where I will tell you that basing this one single block will take you as long as building a two to three foot tall wall on top of it. Just putting this one block in, you should be able to stack the next two to three feet up, as fast as it takes you to get this one block in place the right way.

Stan: All right, so pretty much there, as I slide it across, I don't have any edges. It's not high, it's not low. As I slide it across, it's perfectly flush there. We also can go on the back side, which I'm running out of room. Go on the back side. Come here, take a look at this real quick, top [inaudible 00:12:07]. Now do you see where I'm tight here, I've got gap here, and I'm tight there? That means this quarter needs to be kicked back, and we use the back side of the block because the front side has a rough face to it, and you can't actually go off of this and get accurate details. So that's good enough. Gives you guys the general idea of what it takes to put this base block in, the type of material you use, and why. 

Stan: I hope this level of detail helps you guys out. I'm gonna need to know from you guys in the comments down below. You tell me. Is this overkill? Am I going way overboard for you guys? Losing you, or is this good stuff for you guys to know? Because this is the stuff that nobody taught me when I was first starting out, and I had to figure out over 20 ... That's also why I hurt every time I step up and down, because these blocks are heavy. But okay, so we've covered drainage, we've covered base material, we've covered retaining wall blocks. We've talked about geo grid. I'm gonna take you ... Oh, let's talk about why these things are mortarless.

Stan: You can see right where the [inaudible 00:14:08] is in place, they've actually mortared this as a preventive maintenance, preventive measure, to try to hold these blocks in place. Man, I'm seeing stuff for the first time that I've never seen before. This whole wall has been mortared. The reason you don't mortar a wall, a retaining wall like this, is because you want the water to pass through. When you mortar it, the water should flow freely through these holes and out, so when you mortar it like you're doing right here, you're stopping, you're blocking that water. And what happens is it allows the whole wall to fail, instead of just in the area behind it. 

Stan: These blocks are mortarless on purpose, and the reason they're mortarless is because they are designed to let the water flow freely through them through the entire course of the block. As we go behind this wall, if water passes through this drainage zone right here, it's gonna funnel into this whole thing, and it's going to weep evenly between every single block. If we had mortared this front face of this wall, what happens is as the water's coming down, trying to get through, it's being blocked. That water gets trapped, and then it can't go anywhere put push the wall out. Worse yet, if you happen to be in the early spring or late fall where you get the [inaudible 00:15:42] cycles, that trapped water is going to expand and contract, and you'll get seasonal movement that's almost equal to anything else that you can experience. 

Stan: So you've got to actually compensate for the concept if you live in an area where you have winters, to calculate for the seasonal movement that's going to be occurring in the retaining wall. You don't want water sitting in between the layers. You want the water to get in, to get out, to get away. You want the water gone. That's why the drainage zone is so absolutely important and fundamental to the overall success of your retaining wall, because it really determines how fast it can get the water away. Water's not your friend in a retaining wall. Not at all. 

Stan: All right, so let's talk about a tiered retaining wall, and why this should bring up an immediate red flag to you if you have a contractor that comes out to your site and only offers you a tiered retaining wall. The typical rule of thumb when you're building a retaining wall is that four feet is the maximum height that you can build a gravity wall without permits. And a lot of times what some landscape contractors will do is they don't wanna get an engineered retaining wall, and it could be because either they don't wanna do the extra work, or they're really not qualified to do it. Now I know a lot of guys are gonna be screaming and yelling and jumping up and down at the top of the screen. 

Stan: I really don't care, because the fact of the matter is an engineered retaining wall takes more steps. Takes permitting, it takes actually having a certified engineer. I don't know why I air quoted because you actually do need a certified engineer to design the wall for you in the first place. But here's the benefits of building a single wall versus a terraced wall. A single retaining wall optimizes the space on top and the space on the bottom. The danger with a single wall when you get with a taller wall that may be six, seven, eight feet tall, is a trip hazard. So when you're actually building that wall as a contractor, you have to take that into consideration and put some kind of a safety or security measure at the top of that retaining wall, whether that's a fence or a hedgerow or something else. 

Stan: Now, there are times when a terraced wall is actually right, and that's if you have a customer that wants to have planting space. Now I'm gonna back up so you can see me, but when I'm referring to planting space, I'm talking about the space in between those walls has to be the ideal distance for planting materials. It should be no lower than waist height, and it shouldn't be too deep that you can't reach and work that bed. Now, a lot of contractors when they're trying to skirt the system and build a terraced retaining wall to avoid the engineering, to avoid the permitting, to avoid all of those things, will make the mistake of building a terraced retaining wall too close together. Here's a general rule of thumb. It's not adamant, but this will help guide you guys along the way. 

Stan: When you build a four foot tall retaining wall, the distance from this retaining wall to the next retaining wall is double the height of the bottom wall. That means if you have a four foot tall wall, you have to go eight feet back before you can start the next retaining wall. That way, the top retaining wall doesn't put a surcharge onto the bottom retaining wall. If you're not that distance apart, you're actually doing more damage by building a terraced retaining wall than if you are a single retaining wall. Here's why. This top retaining wall will eventually blow out and push out the bottom retaining wall. So when you shorten that distance between the two retaining walls, the bottom wall will actually need more geo grid, more fortification, than a single retaining wall. Sounds kinda odd, but it's the truth. So if you have a contractor come out to your site and only offers you terraced options, there may be a whole bunch of red flags that I want you to start to think about, so that you guys can make the right decision on your project. There's advantages to terraced walls, there's advantages to single walls. But whatever fits your yard is gonna be the best fit for you. Yeah. There you go.

Stan: Now here's the thing. Acting as one unit is absolutely no problem, as long as you design it and get the engineering and the permits for it. That's why a lot of times you'll see guys offer terracing as a viable option. It's not because it's better for your project, it's better for them to avoid scrutiny on their construction techniques. Now in this situation and most retaining walls, I prefer one wall. I prefer to engineer it, build it as tall as we need to, and then put the safety guards in place on top of that wall to make sure that nothing happens to anybody falling over. The reason I like to do one wall whenever possible is because it optimizes the space on the top, and it optimizes the space on the bottom, and then you don't have this odd distance in between that's difficult for planting. It's difficult for maintenance, it just becomes an unusable difficult space. In fact, if you look at this, you can tell nobody's ever done anything with this space between these two walls. It's just wasted yard space. 

Stan: All right, guys, I kind of feel like I built this whole retaining wall topic to death in the last two video series, but I don't know. So you guys gotta tell me. What do you think of this? Do you like these way in depth detailed videos that maybe hopefully you guys can use for training or for whatever purposes just to make your projects and lives better? You tell me in the comments down below, and what's next? What's coming up? You tell me. A lot of times, you guys plant these little seeds. You make these little suggestions, and you guys know I read everything you do. I can't respond all the time, but I read absolutely everything you say, and so a lot of times these videos are inspired by you guys. So you tell me what's next in the comments down below. God bless, hope your retaining walls absolutely rock. Go get 'em. 

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