It is one of the basic but most important elements in any type of construction project involving cementitious materials. At times, “Shuttering” is often confused with “Formwork”. Though the two refer to the same process, there are slight differences.
Shuttering Oil for plywood involves creating construction moulds using plywood, while Formwork includes moulds made with various other materials. Shuttering and Formwork are both used for the same purpose, with their materials being the only difference. Usually, the type of structural elements and materials being used determine the type of mould needed for a construction project.
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Generally, Formwork uses a mix of wood and non-wood materials to make moulds. Most common type of material used in Formwork is timber. This is because timber has incredible properties, such as the ability to shrink, swell and warp without getting damaged.
However, shuttering oil is the final element required to create smooth and even surfaces once the shuttering or formwork is removed. It is also called mould release agent, or de-shuttering oil too.
What Is Shuttering Oil? Shuttering Oil For Plywood Is Work?
It is a high-quality mineral-based oil that is applied to the inner surface of shutters or formworks before laying concrete. It creates a thin layer between the formwork and the concrete without affecting the curing process. Once the concrete gets sufficiently hard the shuttering oil makes it easier to remove the mould without damaging the formwork or affecting the finish quality of the concrete surface.
High-quality mould release agents prevent the concrete from sticking to the mould surface. This helps to efficiently strip formwork or shutters once the concrete gets hard enough. The de-shuttering oils also protect the mould from corrosion by creating a greasy layer between it and the concrete, thus preventing damage from water.
In addition, a mould release agent helps reduce leakage of water during the concrete curing process. This is very helpful when using wooden moulds, as the shuttering oil prevents water absorption from the concrete. It also ensures that the surface finish is smooth and even, with minimal defects.
Lastly, shuttering oils also protect the mould, irrespective of the material. This way, you can re-use the formwork or shutter multiple times without needing to replace it. De-shuttering oils essentially lower the cost of maintenance of moulds and minimize the expenses of replacing worn-out and damaged moulds.
How Does Shuttering Oil For Plywood Work?
It mainly works by creating a thin film of water-repellent compound between the mould and the layer of concrete. They are classified into two categories, according to how they work – Barrier Agents and Reactive Agents – and you may also find de-shuttering oil made by combining these two.
Barrier Agents form a barrier between the mould surface and the poured concrete. This barrier physically prevents the concrete from sticking to the mould surface.
Earlier, people often used paraffin wax, home heating oil, or even diesel oil as a barrier-based mould release agent. However, these usually require to be applied in large quantities which often leave stains and small surface voids in the concrete. Applying it too early usually causes the oil to evaporate, thus making the process tedious and expensive.
However, branded de-shuttering oils are highly trusted barrier agents in construction projects.
Reactive Agents are available in different formulations. The main component in these mould release agents is an active ingredient which is usually derived from a plant or animal source. It chemically combines with lime (calcium) in fresh concrete. This reaction produces a fine film of metallic salt, soap or grease, just like a bathtub ring. This non-water-soluble film forms a protective layer, which allows you to remove moulds easily once the concrete gets hard.
The reactive components in such mould release agents are usually biodegradable, which makes them safe for use by humans and eco-friendly too. Normally, chemically reactive de-shuttering oil needs to be diluted in a water- or oil-based carrier before use. It can also come as a concentrated chemical that you may need to mix with a specific suitable carrier.
Are There Different Types Of Shuttering Oil?
Yes, there are different types of Shuttering Oil for plywood available in the market. These are usually classified into different categories according to their components.
Let’s look at some of the most common varieties of Shuttering Oil for plywood you can buy today –
De-Shuttering Oil (DSO)
It is a water-based mould release agent. It provides a stain-free and smooth finish to the concrete surface. You can spray DSO mould release agent directly on the required mould surface.
However, you will need to be careful about applying excess oil. In case the thickness of the oil layer is higher than the recommended values, you should drain the extra oil before it dries.
Using DSO offers several significant advantages. For instance, water based Shuttering Oil for plywood is economical to use. It is made from non-toxic and non-hazardous chemicals to make it completely safe for use by humans. Besides, de-shuttering oil is designed for use with all types of concrete moulds. In essence, a DSO mould release agent gives incredibly smooth and even texture to the concrete surface.
De-Shuttering Oil Concentrate (DSOC)
It concentrate is like DSO and is easy to dilute in water. It is an excellent mould release agent. Before use, you simply need to dilute around 1 part of the volume of water to 5 parts of the volume of de-shuttering oil.
De-Shuttering Oil Emulsion (DSOM)
De-shuttering emulsion comes ready-to-use. You do not need to dilute DSOM with water and it can be used instantly on the construction site.
Conclusion
De-shuttering oil, or mould release agent, is a crucial element in construction to ensure smooth, even, and strong concrete surfaces. It is required to create a distinct barrier between the surface of the mould and the concrete being poured into the formwork. This helps to prevent the concrete from adhering to the formwork surface during the hardening process. With this, it is easier to remove the formwork or moulds once the concrete gets dried. It is essential to achieve uniform texture and color on the concrete surface after the mould is removed.