Do-it-yourself concrete floors are not difficult to install, but they take patience and attention to detail to produce a final product that is straight, free of cracks, and ready for daily use. One of the most important steps in installing do-it-yourself concrete floors is determining how much concrete is necessary to fill the desired surface area. This can be done by simple mathematical calculations, but one should be sure to double check the math before purchasing the concrete. It is always a good idea to purchase one or two extra bags of concrete, just in case the calculations are off.
Before pouring do-it-yourself concrete floors, the installer should prepare the surface upon which the concrete will be poured. This usually involves digging into the dirt, flattening the surface, pouring a layer of crushed stone, gravel, or cinders, and tamping it all down flat. This sub-layer needs to be as flat as possible to provide an even surface on which the concrete can dry and settle. To check if the sub-layer is flat before pouring do-it-yourself concrete floors, pound stakes into the four corners of the floor area and tie string to each corner. The string should be measured a few inches off the sub-layer at various locations. Place a level on the string to see if it measures out level. This is just a rough estimate, so if the level is far off, adjust the layer accordingly.
Thicker do-it-yourself concrete floors will require rebar within the structure to keep the concrete from separating or cracking after time and under different weather conditions. Rebar can be purchased at most hardware stores, and it must be cut to a proper size for the floor. This can be done using cutting disks on a circular saw or angle grinder, or it can be done at the hardware store if the measurements are obtained ahead of time. Be sure to purchase rebar supports that hold the rebar off the sub-layer. These are usually quite inexpensive and easy to put in place; they will hold the rebar up off the sub-layer so it ends up in the middle of the drying concrete rather than on the bottom of it.
Curing the concrete takes some special attention. Make sure the concrete stays appropriately moist during the initial curing and leveling, and if the concrete floor is outside exposed to the elements, be sure to cover it with a tarp as it dries. This will keep debris and excess moisture off the slab. Let the concrete cure for up to 48 hours before continuing with the building process.