Formwork is a term used in the construction industry. This is a mold or casing in which concrete, cement or some other building material is poured to form structures of various sizes and shapes. There are many types of framework or shuttering material available in the market to construct formworks. Apart from aluminium, steel and plastic, shuttering plywood is also used as form works. Shuttering plywood is a BWP grade plywood which is designed for use as form works for concrete and other materials.
Shuttering plywood is a densified plywood. The plywood shuttering design consists of many layers of core veneers such as 9 or more. The adhesive used to bind the layers must of BWP grade. Phenol formaldehyde which is a synthetic resin is used as an adhesive. Preservatives are also added to make the wooden veneers more durable. The veneers are rotary cut or sliced and it is ensured that the veneers have a very smooth surface. The layers are placed at right angles to each other, bound using the adhesive and pressed together under high temperature and pressure to create shuttering plywood.
There are three types of shuttering plywood as per Indian Standards. They are as follows.
Plain plywood shuttering designated as CS shuttering plywood
Plywood shuttering with plastic coating or plastic coated shuttering plywood. Designated as CSC shuttering plywood.
Plywood shuttering with an overlay on the faces or film faced shuttering plywood. Designated as CSFF shuttering plywood.
Type of Wood Veneer used
The wood veneers used in plywood shuttering boards can be obtained from any type of wood species. The timber species can be Indian Oak, Birch, Gurjan, Gamari, Bahera, Elm, Poplar, Rosewood, Mango, Walnut, Teak, Maple and White Cedar to name a few. Eco Mark is given to only those brands of shuttering plywood which use veneers from sources other than natural forests. The species include rubber, cashew, shade trees in tea and coffee gardens and social forestry and industrial plantations.
Creating formworks for various types of structures constitute shuttering plywood uses. Shuttering plywood is used to make casts for pillars, ceilings, walls, beams, floors, etc. Shuttering plywood is also reusable. An used shuttering plywood of good quality can be reused 20-25 times.
Size and thickness
Shuttering plywoods are available in standard sizes and thicknesses. However, the dimensions can be customised according to needs. The standard shuttering plywood sizes are as follows.
2400mm x 1200mm
2400mm x 900mm
2100mm x 1200mm
2100mm x 900mm
1800mm x 1200mm
1800mm x 900mm
1500mm x 1200mm
1500mm x 900mm
1200mm x 1200mm
1200mm x 900mm
1200mm x 600mm
900mm x 900mm
The thicknesses of the shuttering plywoods vary according to the number of venners used in them.
The shuttering plywood price in india depends upon various factors apart from the dimensions of the sheets. The factors include timber species of the veneers, type of adhesive and preservative used, density of the plywood, load capacity of the plywood and the maximum bendable radii of the plywood during concrete work.
The shuttering plywood rate in India usually ranges between Rs 45 to Rs 255 per square feet. The shuttering plywood price list by a manufacturer is usually on a per square feet basis
Let us take the example of 12mm shuttering plywood price. A waterproof shuttering plywood of 12mm thickness with a size of 6ft by 4ft can cost Rs 45 per square feet. A film faced shuttering plywood 12mm of 8ft x 4ft size can cost as much as Rs 4000 per sheet.
Another example can be of shuttering plywood 18mm. A teak shuttering plywood of 18mm thickness can cost Rs 62 per square feet. The 18mm shuttering plywood price in case of a film faced and moisture proof variety can be Rs 58 per square feet.
The shuttering plywood price is also influenced by brand, suppliers and locations. The shuttering plywood need to be selected according to requirements, application and budget.
Essential requirements of shuttering plywood
These are some of the major requirements for shuttering plywood sheets.
Shuttering plywood must be able to withstand changing wet and dry conditions.
Shuttering plywood must be hard enough to tolerate the force exerted on it by the concrete when it cures.
The dimensions of a shuttering grade plywood needs to remain stable under heat generated by the concrete during curing process.
Shuttering plywood must have a very smooth surface so that concrete does not stick on it. Concrete also gets a smooth finish due to smooth surface of the shuttering plywood. Film faced shuttering plywood is the best in this regard.
The shuttering plywood must be reusable multiple times.