How To Build Concrete Formwork
Building a concrete form and pouring your own slab can save you a lot of money, but it can also be extremely intimidating. Just the slightest mistake and your entire project can turn into one big mess that will be hard to correct.
With that being said, you should know that the formwork is an extremely important part of any concrete job, as it holds your concrete in a certain shape until the mixture hardens.
If the formwork doesn’t hold up under the pressure, it can ruin the project and make it misshaped. This is why it is imperative to know everything that you possibly can about formwork and how to properly build formwork.
Properly Preparing The Site For A Slab
Once you have your site picked out and you know exactly the size of the slab that you want to pour, you will be ready to begin preparing the site for your formwork. Keep in mind that your concrete slab is going to last longer and experience less cracking and movement if the formwork is constructed on solid, well-drained soil.
If you are working with sandy type soil, you are in luck, because there really won’t be much else that you have to do besides level the area and build the formwork.
However, if you are working with clay or loam soil, you will have to remove enough of the surface to allow for 6 to 8 inches of compacted gravel, which will be poured before the new concrete.
Depending on the size of the slab that you are pouring, it might be best to hire an excavator or rent a skid loader to remove the excess soil in a time efficient manner. Removing 6 to 8 inches of soil over a large surface with a shovel can be a lot of hard work.
Marking Out The Dimensions
Now, that you have the area prepared, you will be ready to go ahead and start marking out the dimensions for your formwork. You will do this by utilizing construction stakes.
Go ahead and drive a stake down in the ground. Take a tape measure and measure to the desired length of your slab and drive another stake. You now want repeat this step two more times until you have a square or rectangle formed.
Choosing Your Floorboards
Now that you have the area levelled and the basic skeleton of the slab formed, you will be ready to choose your floorboards. These are the boards that are going to be nailed or screwed to the stakes, which will hold your concrete in place as it is poured.
Depending on the height of your slab, you can literally use a 2×4, 2×6, or even 1×4. Just make sure that they are free of knots and straight. Once you know the size of the floorboards that you want to use, go ahead and nail or screw them to the stakes that you already had in place.
Depending on the size of your slab, it might be a good ideal to add some more stakes to support the weight on the concrete. Once everything looks good, you should go ahead and move on to the next step.
Adding Chicken Wire And Rebar
It is absolutely vital to make sure that the frame is going to be stable and sturdy after the concrete is poured. If it is not, there is a good chance that the weight of the concrete will cause the frame to break and the concrete will seep out.
Using chicken wire can help. Rebar is a must for parking areas. The rebar should be inserted into the ground. Then, attach the chicken wire around it. Be sure to pull upward on the chicken wire. Positioning is very important. It is essential to make sure that the concrete will be under and above the wire.
Doublecheck Your Work
Finally, you should go ahead and doublecheck your work. In order for concrete to be laid perfectly, it is essential for everything to be right. Check the frame once again and make sure it is sturdy.
Also, use a leveler to guarantee that everything is flat and straight. Eyeball the frame and make sure that nothing looks out of place. If everything is good to go, you’ll be ready to pour the concrete.