A concrete formwork, by definition is the system of supports and boards that provide support to the concrete until it cures since concrete is considered to be an aggregate like sand and coarse gravel, cement that serves as the binder, and water. Given such, concrete is a heavy material with the water mass and aggregate. The form needs to be a material that could withstand the pressure. In most cases, a contractor will be using a one-inch thick plywood. Also, the forms should be reinforced every 16 inches or 2 feet that comes with a brace that is anchored into the ground.
Achieving a Clean Edge
The mass of the concrete will be pushed out and will flow everywhere, but in order to have a clean edge, the walls of the formwork needs to be extremely strong in order to withstand the pressure. Thus, the vertical bracing needs to be driven deep into the ground. Any sign of softness in the earth would translate into sagging stakes.
Once these stakes sag, the form will bulge. This will then result to concrete that cures crooked. A stake that badly formed is difficult to correct with wet concrete. The mass of the concrete is heavy and concrete hardening is another factor to consider. Concrete can cure within minutes and you can forget about adjusting the formwork for any deviations. If the form bulges and the concrete cures, it’s possible to make use of a diamond blade concrete chop saw to trim the concrete. However, this can be a dirty process and even time consuming.
You also need to bear in mind that since curing is a chemical process, the concrete may bind to the forms. This, you can use formoil on form surfaces. The oil will stop the concrete from binding to the form. At the same time, the concrete expands as soon as it dries so you will need an expansion joint between the house and the patio.
The expansion needs to be inserted which absorbs the movement of the slabs. Lastly, for your concrete detailing, you will be needing some scoring tools and concrete float finishing. In order to achieve a smooth surface, the finishing tool will be drawn across the top surface to smooth out the finish and the expansion joint scoring tool that creates the needed cracks.
Moreover, with a little preparation, you can have that beautiful patio that you and your loved ones can enjoy and this will be the result of your good and solid concrete formwork. In case you still feel intimidated, there will be experts in the field of concrete consulting who can provide help with the project. An attractive driveway or concrete patio can last for so many years to come.