Film Faced Plywood - Plywood formwork
The initial cost of metal formwork is more than timber formwork but the number of reuses of metal formwork is higher than that of timber. In the long run metal formwork can be economical. In heavy construction works metal formwork may require a lifting mechanism to handle the formwork panels or props. Steel or aluminum or magnesium is the most widely used metals.
Steel can also be used as formwork material. It is very costly but it can be used for more times than others. They provide an excellent finish to the concrete surfaces. For mass structures like dams, bridges, etc. steel from work is so strong and safe.
- Steel forms are durable and stronger.
- Provides uniform and smooth surface finish to the structure.
- Great reusability.
- Easy to fix the formwork and also easy to dismantle.
- Cost is very much higher.
- It is heavy in weight and requires lifting equipment for large structure formworks.
- Corrosion will occur when there is frequent contact with water.
- The size and shapes of forms available are limited.
Aluminum formwork is used often for pre-fabricated formworks. It is getting more popular because of its lightweight and good strength. It requires fewer supports and ties.
- Easy to fix and easy to dismantle.
- It can be handled easily because of its lightweight.
- It can be re-used for many times.
- The walls and slabs of structures can be casted simultaneously.
- Monolithic crack free structures can be built using aluminum formwork.
- When the load reaches its maximum limit, the lighter sections may deflect.
- Architectural modifications are not possible when aluminum formwork is used.
Plastic is another type of formwork material that is used for small concrete structures or for complex portions of the structure. It is light in weight and durable for long periods. For complicated concrete structures, Glass-reinforced plastics (GRP) and vacuum-formed plastics are used.
- Plastic is light in weight and can be easily handled.
- Formwork for complex-shaped structures can be prepared easily.
- Good resistant against water.
- The damaged plastic sheets can be recycled and useful to make new sheets.
- Good quality plastic has great re-usability.
- Plastic is weak against heat.
- It is a costly material.
- It does not take much load when compared with others.
- It must be capable to withstand all types of dead and live
- It is practically good to have a waterproof character so that it won’t absorb water from concrete.
- Entire formwork should be rigidly constructed and propped so that there should be no deformation in the shape and retain its original shape.
- Deflection and shrinkage should be minimum.
- The joins should be tight enough to minimize the leakage of cement grout.
- The formwork should be constructed with different segments. So that while removing the formwork it should not damage the concrete
- The material of the formwork should be cheap, easily available and should be suitable for reuse.
- The formwork should be set accurately to the desired line and levels should have plane surface.
- It should be as light as possible. So that it is easy to transfer and erect.
- The material of the formwork should not warp or get distorted when exposed to the elements.
Depends on those requirements, Fomex Group offers some recommendations to optimize the usage of formwork materials to meet the majority of user’s demands.
Plywood formwork is a lightweight, durable and eco-friendly system that provides a high-quality concrete cast surface. It is prepared by combining the specially prepared three layers on top of each other. Plywood formwork is applicable wherein a large surface needs to be coated with a light and durable material. It is especially preferred in molds prepared for pouring concrete in constructions. Usually, plywood boards are made of birch, poplar, spruce, or pine but there are many types of materials used by plywood manufacturers in different parts of the world. While the type of plywood used is important, the real opportunity for making a difference for the final concrete result is the type of coating: the film that is applied on the plywood surface.
Fomex Greenwood - Film faced plywood
Plywood has the natural property to absorb moisture, resulting in a sponge effect. This causes movement of the panels, affects the weight and the mechanical properties of the material, ultimately influencing its life cycle. Its advantages include:
- Provides high-quality concrete cast surface
- Favorable for weight to strength ratio
- Minimal deflection due to inherent stiffness
- High durability
- Can be reused
- The panel shear of plywood is nearly double that of solid timber due to its cross laminated structure.
- Easy to machine and fix using standard machining and fastening methods
- Easy to handle on-site
- Good chemical resistance
- Wide variety of different overlays and sizes are available
- Plywood has ecological importance.
So, the conclusion is that plywood is the most suitable material, meeting most of the material requirements of formwork.