What are Concrete Forms?
Concrete is an extraordinary product. It is actually in semi-solid form. It can be worked upon and manipulated to take nearly any shape. It then hardens and takes that shape. It is a building material that is used the most in the world thanks to its ability to assume shapes and fill voids. This would not have been possible if there were no concrete forms.
In simple words, concrete forms are actually solid barriers. Concrete is held in place by the forms. They also force concrete so that it takes a certain shape. The newer systems of formation serve many other purposes too like imparting decorative effects or providing insulation. A square foot of standard concrete weighs 150 pounds. A typical project involving concrete could need hundreds or thousands of square feet of the material to be used at a time. The forms hold all of that weight. This is why they are made of metal or rigid metal.
Types of Concrete Forms:
- Insulated Concrete Forms (ICF)
- Concrete Wall Forms
- Foam Concrete Forms
- Wood Forms
- Plastic Forms
- Concrete Metal Forms
ICFs are the most popular type among these. In the past few years, there has been a lot of progress with forms being made of resins, fiber glass and plastic. However, the strength and cost of such materials cannot really surpass the performance of wood and metal.
Concrete forms are usually categorized as per how and where they are being used. The ideal form for a specific project is generally a function of pour size, the quantity of concrete a form has to retain and the weight or pressure that will push against the concrete form. For instance, the forms that are typically made use of for flatwork like road, sidewalk, patio or driveway have heights in the range of 3 – 12 inches. Most of the weight of concrete in applications of flatwork is spread across a sub-base that is pre-prepared. This relives a lot of the weight that pushes against the concrete form. Such forms are usually made of wood.
Metal is used for highway or larger commercial work. A form that is used for constructing the foundation of a high rise structure or bridge pier will hold hundreds or thousands of square feet of the material with heights in the range of 12 – 20 feet. As enormous weight is exerted against the forms, they are constructed of high quality steel and weigh thousands of pounds.
Concrete Forms Installation
No matter what kind of forming system or form is used, the factor that is most important for achieving great results is the installation of the forms. Forming tends to be ignored in the construction of concrete but the right system and installation that is done professionally has a great impact on the strength as well as appearance of concrete. If the form is installed properly, it will give a smooth and uniform surface with few defects on the surface and clean edges.
The increasing availability of common materials for concrete forms at big box and local hardware stores has resulted in a proliferation of weekend warriors and do-it-yourselfers trying concrete forming as well as pouring, especially of countertops. Unless you know what is to be done, it is best to get a professional to do the forming.