PLYWOOD AS A CONSTRUCTION MATERIAL-ALL YOU NEED TO KNOW
Plywood is very widely used in construction. This is because it has many useful properties that are suitable for construction. Plywood is a factory-produced material that has precise dimensions made from three or four sheets of wood. These sheets are glued together to form a thicker sheet. Plywood is very light in weight and very durable.
It can be used in both the interior and exterior areas of a building. That is why it is so commonly preferred by builders and house owners. Plywood is an engineered wood sheet material made up of fine layers or flimsy strands of wood veneers attached together placing wood grains 90 degrees to one another. It is one type of manufactured board which can be described as a mixture of Medium Density Fibreboard (MDF) and Chip Board (Particle Board). It is a complex material and attaches resin and fiber sheets of wood
Plywood as a building material is very widely used due to its many useful properties. It is an economical, factory-produced sheet of wood with precise dimensions that does not warp or crack with changes in atmospheric moisture.
Ply is an engineered wood product made from three or more ‘plies’ or thin sheets of wood. These are glued together to form a thicker, flat sheet. The logs used to make plywood as a building material are prepared by steaming or dipping in hot water. They are then fed into a lathe machine, which peels the log into thin plies of wood. each ply is usually between 1 and 4mm thick.
“Plywood is very light in weight and very durable. It can be used in both the interior and exterior areas of a building. That is why it is so commonly preferred by builders and house owners.”
USES OF PLYWOOD AS A BUILDING MATERIAL
Plywood has a huge range of used within the construction industry. Some of its most common uses are:-
- To make light partitions or external walls
- To make formwork or a mould for wet concrete
- To make furniture, especially cupboards, kitchen cabinets, and office tables
- As part of flooring systems
- For packaging
- To make light doors and shutters
- Low moisture plywood is used for different purposes like ship making.
- For making surfaces shaped curved, u, or folded plywood is used as the grains of plywood is easy to make bend than normal wood.
- To make the interior surface of skating ground this is used.
- Used for different interior games stadium.
- For ship construction.
- For space or aviation parts making.
PROPERTIES OF PLYWOOD
High Strength: Plywood has the structural strength of the wood it is made from. This is in addition to the properties obtained from its laminated design. The grains of each veneer are laid at 90-degree angles to each other. This makes the whole sheet resistant to splitting, especially when nailed at the edges. It also gives the whole sheet uniform strength for increased stability. Furthermore, plywood has a higher strength-to-weight ratio as compared to cut lumber. This makes it ideal for flooring, webbed beams, and shear walls.
High panel shear: Plywood is made with an odd number of layers, making it tough to bend. The angle at which the veneer grains are laid against each other may be varied from 90 degrees. Each veneer can be laid at a 45 or 30-degree angle to the next one, increasing the plywood’s strength in every direction. This cross lamination increases the panel shear of plywood, important in bracing panels and fabricated beams.
Flexibility: Unlike cut timber, plywood can be manufactured to fit every requirement. The thickness of each veneer can vary from a few millimeters to several inches. The number of veneers used also ranges from three to several, increasing the thickness of the sheet. The extra layers add more strength to the plywood. Thinner veneers are used to increase flexibility for use in ceilings and paneling.
Moisture resistance: The type of adhesive used to bind the veneers makes the plywood resistant to moisture and humidity. A layer of paint or varnish can also increase resistance to water damage. These types of veneers are suitable for exterior use such as cladding, sheds, and in marine construction. They are also suited for holding concrete while it sets. Moisture resistance is important in interior applications as well, including on floors. The cross lamination ensures the veneers do not warp, shrink, or expand when exposed to water and extreme temperature.
Chemical resistance: Plywood treated with preservatives does not corrode when exposed to chemicals. This makes it suitable for chemical works and cooling towers.
Impact resistance: Plywood has high tensile strength, derived from the cross lamination of panels. This distributes the force over a larger area, reducing tensile stress. Plywood is, therefore, able to withstand overloading by up to twice its designated load. This is critical during short-term seismic activity or high winds. It is also useful in flooring and concrete formwork.
Fire resistance: Plywood can be treated with a fire-resistant chemical coating. More commonly, it is combined with non-combustible materials such as plasterboard or fibrous cement. This makes it ideal for use in fire-resistant structures.
Insulation: Plywood has high thermal and sound insulation. This makes it a useful insulating material for flooring, ceilings, roofing, and wall cladding. Insulation offered by plywood can greatly reduce heating and cooling costs.