Hello, I'm Tim Carter from AsktheBuilder.com. I have some exciting things to show you today. We're here at the job site and the concrete truck is here and we are getting ready to pour the concrete foundation footer. Check this out.
The workman, down in the hole, had set up a bunch of wood forms and it is filled with wet concrete. He is smoothing it off. The forms are level and he is giving the footer a nice finish even with the tops of the forms.
The truck is getting ready to pour concrete in another section of the footer. Watch how this is done. You can see if you have good access with the truck, you can have the truck do most of the work. You can see the concrete flowing down the chute. Notice the consistency of the concrete. It flows right into the footer forms. The worker just guides the concrete around the rebars. You will recall that the rebars give the footer concrete a lot of tensile strength. The driver is helping by backing up and getting the concrete in the right spots. By directing the chute right to left and adjusting the concrete flow, he can provide just the right amount of concrete into the footer. Plus the worker isn't overwhelmed with too much concrete.
That is how you pour a concrete footer or a foundation footer for a home.
Hello, I'm Tim Carter from AsktheBuilder.com. I'm here in New Hampshire on the western shore of Lake Winnisquam at a construction site. They are getting ready to build a garage for a residential home. And I am not in the hole and have something very interesting to show you that most people don't get to see because it happens so quickly.
What happened is yesterday they dug the hole in order to pour the footers. What we are seeing are the forms where the footer will be poured. First, what's a footer? The footer is the first thing that is generally constructed on a house build. It is the thing holds the foundation and spreads the weight of the entire structure over a larger area of the soil surface. This creates a wider footprint.
Image if you poured a foundation directly on the soil, if the soil got wet or the structure was very heavy, the foundation could cut through the soil like a knife blade goes through butter. But image if you turn the knife blade on its side and try to push it through the butter, you will find it will be very, very hard to get through the butter. That is what a foundation footer does.
Another thing a foundation footer does is provides a nice level surface so that the foundation forms can be placed with relative ease.
Let me show you two other things that are important with a footer. Down inside the footer forms are steel rods. These are 1/2" rebar. There are two rods that are suspended in the air. This allows the concrete to completely flow around the rebars. In addition, these rods go continuously around the footer. These steel rods give the concrete tremendous tensile strength so if the footer were to crack or try to separate, it would have to try and rip apart the steel bars. You can image how hard that is.
Look at this. The footer in the back corner has to go up to get over a section of solid rock. The footer had to jump up over the solid rock areas. Extra rods have been drilled into the rock so that the footer won't slide off the bedrock. Once the footer forms are past the bedrock, it drops back down to the original height.
So that is a concrete footer and what they look like before the concrete trucks show up. The footer is what supports the weight of your home. It is very important that these are installation correctly. The soil under the footer must be compacted completely and has past the soil inspection by the building officials. Make sure that happens on your job.
Hello, I'm Tim Carter from AsktheBuilder.com. Let me show you how a real powered screed works on concrete work. Up close and personal. Watch this.
Isn't that interesting and amazing. Look how easy it is to smooth the concrete with a powered screed. Got to get one if you are doing a lot of concrete work.
Hello, I'm Tim Carter from AsktheBuilder.com. I want to show you how they use a bull float to float a concrete slab. Watch this. The operator lifts the float slightly on the return pull and moves it back and forth. What the bull float is doing is helping to push some of the bigger aggregate down that is close to the top of the concrete a little bit down inside the slab.
In addition, the bull float is giving a smoother surface to the slab. So when they go to trowel the concrete, it is a lot easier to get a nice smooth finish on it.
This bull float has a nice long handle on it to reach all the way across the slab. The operator lifts up on the handle and turns it slightly and pulls it back, creating that nice smooth surface without standing on the slab.
All that is needed is a nice gentle touch to float it across the concrete. The concrete is way too wet to stand on, so the bull float allows the surface to be worked without being on the concrete slab. The vibration from the operator helps drive those bigger rocks down into the concrete. You want just some sand and Portland cement to be in the upper 1/4" of the surface.
That's how a bull float works. You will need one when pouring your concrete slab.
Hi, I'm Tim Carter from AsktheBuilder.com and we are here at a job site today, where they are getting ready to pour a concrete slab. I want to show you something before we get started. First, I am sure you can hear and see the concrete truck getting ready to pour concrete.
Next let's talk about the tools used on a concrete job. Check this out. Here are two concrete rakes. They are just regular tools that look like a normal rake, but a little funnier. They have solid fronts on them and they have a hook on the front edge. The hooks are used to pull up the wire mesh as the concrete is being poured.
The concrete workers will use magnesium floats along the edges to help place the concrete up against the walls. In addition, they will use a bull float to smooth out the surface of the freshly poured slab. Another great finishing tool is the powered screed. This tool vibrates and smooths off the concrete and get it all in the same plane.
Those are some of the tools that will be used during the pouring of a concrete slab. You will need most of these tools when doing your concrete work. You might not have the large power-screed. In the older days, they used a nice straight 2x4 piece of lumber. There is also an aluminum screed that looks like a 2x4. That provides the nice straight edge. Be sure you have the proper tools when it is time to pour your concrete slab.
Hi, I'm Tim Carter from AsktheBuilder.com and we are here today getting ready to pour a concrete slab. But we have an interesting situation. It's a little after noon, and it's about 42 degrees. It is going to get colder as the day goes on and we are going to run out of daylight in about 4 hours.
That's the recipe for concrete not to get hard out of the truck. And look what's happening with the truck right now. What you see is the concrete truck spinning the drum rapidly. About 5 minutes ago, the driver put in a 50-pound bag of calcium chloride flakes into the drum. He is mixing it right at the job site. What the calcium chloride is going to do is accelerate the hydration reaction in the concrete, which makes it go from the plastic state to the solid state.
The concrete finishers need that to happen as quickly as possible so they are not here at midnight, in the dark, trying to finish this concrete slab. Calcium chloride, you can add it to concrete to make it set up faster.
Hi, I'm Tim Carter from AsktheBuilder.com and I want to show you, as they continue to pour the slab, an important thing. Look at this. The entire half of the slab is now screeded. But in one corner there is not concrete. Why do you think there isn't any concrete there?
The reason why is the last thing you want to do is to put too much concrete in the area or hole. If you do, you will have to shovel the excess concrete out of the slab. But if you take your time and work with the truck driver, you can make sure that there is just enough concrete down where it is needed. In this case, they are now filling in the last section.
Keep in mind, you are going to work hard enough as it is putting the concrete down. You don't need to be shoveling extra concrete out of the hole. So screed as you go to be sure there is just enough concrete in the area. It's as simple as that.
Hi, I'm Tim Carter from AsktheBuilder.com and we are here continuing to pour the concrete slab. I want to show you a neat tool they are getting ready to use. It's a power screed. It's really, really cool.
It has a small gasoline engine on it. That gas engine causes, through a cable, a vibration in the long blade of the screed. In this example, the workers have created two spots that they are screeding against. You will notice a spot right along the wall and the other spot in the middle of the slab.
They start at the wall and move the screed towards the center. This floats the surface of the freshly poured concrete. The operator just gently pulls the screed along the concrete, but the surface is smooth after the screed passes over it.
With a nice long pull, the powered-screed smooths a wide section of the slab. This keeps the scab surface in the same plane. You can definitely see the difference between the screeded section and the untreated areas. In the old days, it would take lots of time to float that much area.
That is a nice powered-screed. I doubt you will have one on your do-it-yourself job, but hopefully if you use professionals, they will have one. It is a great tool to do a lot of work in a small amount of time.
Hi, I'm Tim Carter from AsktheBuilder.com and I want to show you a concrete finisher using a magnesium float to float the edge of some freshly placed concrete. Watch this.
That's how you would use a magnesium float when you are doing concrete work. Did you notice what he did? He puddled the concrete by pushing it up and down. Followed by some real nice gentle strokes to make sure the float stays along the chalk line that is on the foundation wall. That is a nice trick to keep the concrete level. The concrete at this point is very fluid, making it easy to use the float on it right now.
Hi, I'm Tim Carter from AsktheBuilder.com and we're getting ready to pour the concrete slab. The truck's here. Check this out!
What's really nice about these front-loader trucks is that the driver is in the cab and he can see exactly what the two workers are getting ready to do. By the driver moving the chute back and forth, he can make their work a whole lot easier.
Watch this. Here comes the concrete. Notice that the workers are using the hooks on the end of the come-alongs to pull the wire mesh up into the middle of the concrete.
Look how fluid that concrete is. It is flowing on its own. You can see how you can use the concrete rakes to just pull the concrete. If the concrete is the right consistency, it just flows. The concrete rakes are sometimes called come-alongs, but they look like a regular rake. They just move the material around to fill all the areas.
What's really important to note is that the concrete driver has stopped the flow of concrete while he lets the men work and place the concrete in the corner. Just a nice controlled work flow between the driver and the workers. Don't let the truck driver get in front of you. Tell him to stop the concrete flow if he is pouring too much, too fast.