If you’ve never heard of ‘formwork’ before, then let us explain: Formwork, in the context of concrete construction, is a mould to which concrete is poured and allowed to harden. Essentially, it is a method for creating concrete structures.
There are different types of formwork and they can be named according to:
- The material that it is made out of (example: timber, plywood, steel…etc.).
- The type of construction component that it is used to make, such as slabs, beams…etc.
- The reusability of it- reusable forms are known as ‘panel forms’ and others are referred to as ‘stationary forms.
It takes a lot of time and money to make concrete formwork. In fact, about a quarter or more of the total cost of making a particular structure goes to building the formwork. Therefore, before you consider the use of formwork for your own project, we suggest that you consult with an expert. For the best services when it comes to formwork hire Sydney’s most trustworthy and hardworking team.
What Makes A Good Formwork?
A good formwork checks of all of the following conditions:
- Should be sturdy enough to bear the required load.
- Should be rigid enough to always maintain its shape.
- Should be complete free from even the tiniest of leaks.
- Should ideally allow certain parts to be removed at will without resulting in damage to the concrete it holds inside.
- Should be built out of material that is generally cheap, widely available and reusable.
- Should be as light as physically possible while being able to carry out its function.
- Should be placed on a firm foundation.
- Should not change its shape when exposed to a different temperature, pressure…etc.
The Different Types of Formwork
Let’s take a look at some of the common formwork types (based on the material they are made out of) used in concrete construction:
Timber
Timber formworks, which are cheap and widely available, should ideally have the following features:
- Have surfaces which are both smooth and even
- Be lightweight
- Be strong enough that nails can be driven into them without producing splits.
One of the main disadvantages of timber is that they tend to absorb moisture from concrete.
Resin-Bonded Plywood
The cost of building these are similar to that of constructing timber formwork. In certain cases, it may be more cost-effective to use plywood, especially when the formwork has to be reused quite a lot.
Steel
Steel formworks are typically made out of thin plates that are fastened together using appropriate clamps, bolts or nuts. These can be made in any size and shape and are commonly utilized in larger construction projects where the same formwork can be reused over and over. In addition, they are appropriate for the construction of concave or convex structures.
In comparison to timber formwork, steel has the following benefits:
- They are stronger and have a longer lifespan.
- They can be reused a greater number of times.
- They are less affected by the elements.
How to Lower the Cost of Formwork?
Since formwork construction is a heavy expense, steps should be taken to cut down costs. One way is to design spaces so that there aren’t many variations in terms of design. This way the number of different formworks that have to be built are kept to a minimum.