How to Make Concrete Slabs

concrete slabby doorway before settingIf you go to your local home improvement store hoping to learn how to make concrete slabs, you will be met with a large number of choices. You are looking for a basic concrete mix. It is a “just –add-water” formula that has portland cement, sand, and gravel in it. You do not want mason mix, mortar mix, sand mix or a re-surfacing mix. You may also find some quick drying mixes.

If this is your first time working with concrete I would recommend that you stay away from this until you are comfortable with how long it will take you to screed and float your surface. If you use the quick dry formula and it starts to set up before you are ready then you’ve got big problems.

Quantity

One challenge that you will face when learning how to make concrete slabs is determining how much product you need to buy. This process requires a little bit of math. In order to use the volume chart that most manufacturers provide on their products, you will need to know how many square feet the area of slab is. You can then use that area and the chart to figure out how many bags of product you will need. It’s a good idea to take a calculator to the store with you.

Once you get the product home, you are going to need something in which to mix the concrete. You can buy a plastic mixing tub that will work, but most folks prefer to use a wheelbarrow because you can dump the wet concrete out of it instead of having to shovel it out. One lesson that you will learn quickly when figuring out how to make concrete slabs is that you don’t want to spend all day shoveling heavy, wet concrete.

Mixing

When you are ready to start mixing, there will be a ratio printed somewhere on the bag that tells you how much water to use. This is difficult to measure when you are doing large-scale projects. Keep adding water a little at a time until the concrete mix reaches a nice oatmeal like consistency and then pour it

If you have a larger budget for your project, you may also want to look into renting a portable mixer. This has a drum on it that spins much like a smaller version of the drum on a cement truck. Pour the bag of dry cement into the drum and add water as the drum spins and mixes the concrete. This is another labor saving lesson that you will learn as you experiment with how to make concrete slabs.

When the drum is done mixing the cement you can pour it directly into a wheelbarrow and dump it exactly where you want it. Keep adding concrete until it comes right to the top of the form that you have built. Don’t worry if you overfill the form a little bit, as this will come off when you screed and float the surface to make it smooth. If you do have any low spots then you can fill them by hand with a shovel before you smooth the wet concrete.

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