What Is Plywood?
Extremely popular in the world of both trade and DIY, plywood is a highly versatile material that can be utilised in a variety of different applications. From roofing and flooring to walls and furniture, plywood offers an extensive multitude of uses, boasting a fantastic array of practical benefits and advantages.
Despite it being such a well-used building component, you may still not fully understand the ins and outs of this popular product, stopping you utilising its properties to the fullest potential. In this handy article, we will cover the what’s, how’s, where’s and whys of plywood to give you a full understanding of this exciting building material.
Let’s start with the basics and answer...
Table of Contents
- What is Plywood?
- Rotation of the Grain
- Where Did Plywood Come From?
- What Are the Benefits of Using Plywood?
- What Are the Disadvantages of Plywood?
- What Can Plywood be Used For?
- Types of Plywood
- Where Can I Buy Plywood?
What is Plywood?
To put it simply, plywood is a building material manufactured from multiple thin layers or “plies” – hence the same ‘plywood’. These thin sheets are glued together with the wood grain of each layer rotated up to 90 degrees from one another. As a general rule, the thicker the plywood, the more plies it incorporates. Plywood is an engineered form of wood from the same wood family as MDF and chipboard but offers superior strength and durability to these materials.
By combining multiple thinner sheets of wood and through perpendicular placement of the grains, plywood can provide superb impact resistance and overall strength. It is for this reason that plywood is used in both construction projects and furniture manufacturing.
Rotation of the Grain
The angular grain rotation of each sheet is called cross-graining. It is usually layer orientated at an angle of 90 degrees, however in some forms of plywood, this angle can be as low as just 30 degrees. High-quality plywood can often feature five plies in steps of 45 degrees (0, 45, 90, 135 & 180 degrees) whilst others even feature seven piles arranged in 30 degree steps (0, 30, 60, 90, 120, 150 & 180 degrees).
Cross graining is utilised in manufacturing for a variety of practical reasons regarding strength and durability. It not only provides a constant standard of strength throughout the entire board, but also helps to significantly reduce expansion and shrinkage which enhances stability. Cross graining also eliminates points of weakness when the sheets are nailed at the edges which in turn prevents splitting.
Where Did Plywood Come From?
Despite its popular use in modern building applications, the history of plywood dates all the way back to ancient times and was known as highly valued and precious material in many time periods. Depicted on a carving in Thebes, it is shown that the Egyptians used to utilise plywood to construct stools, furniture, tables and even tomb cases as far back as 3500 BC. The manufacturing process was similar to that practised today with sawn veneers glued together in cross graining.
Probably its most fundamental era of use, plywood also played a key role all throughout World War II. Thanks to its impressive strength and durability, plywood was used to construct barracks, weapons, boats and even planes with the introduction of higher-grade synthetic water-resistant glues that ensured much sturdier installation.
Before its use in construction, early examples of plywood were mainly found in the construction of home décor. Assembled using decorative hardwoods, plywood was and is often used to build household furniture such as tables, doors, chests and cabinets.
What Are the Benefits of Using Plywood?
First making its construction appearance in the early 20th century, plywood has progressed dramatically in its level of practicality and durability. With its easy-to-use, fully reliable structure, plywood is a building material that most builders and DIYers find themselves reaching for in range of projects. The question is, why? Well, here are the Top 5 Benefits of Plywood to give you a better idea.
1. Strength & Durability
As previously mentioned, plywood is strong, very strong. In comparison to solid wood, plywood offers far superior strength that is evenly spread all over the board instead of just along the grain. It is even described as one of the strongest building materials out there which is mainly due to the perpendicular placement of the sheet grains. When installed with high-quality adhesives and veneers, plywood provides fantastic resistance to scuffs, blows and any other effects of consistent use. Again, thanks to the cross-layered structure, it also doesn’t split when driven through with a nail or screw.
In most timber merchants you will find plywood from various regions, each boasting their own common species of wood. Whilst Chinese plywood is the most common, it offers lesser strength than Indonesian and Malaysian plywood, which is considered as a much higher quality wood and is ideal for use on load-bearing projects. Russian Birch plywood is widely considered to offer the most consistent level of strength out of the different varieties.
2. Attractive Appearance
As well as impressive strength, plywood also forms a brilliantly clean and professional visual finish. Plywood panels are usually covered with solid wood to create a natural aesthetic that beautifully resembles the organic feel of real wood. Paired with a high-grade veneer or stain, plywood boasts a sleek appearance that looks extremely high-quality.
3. Great Value for Money
For a number of reasons, plywood is also seen as a brilliantly cost-effective building material option. The affordable price point is what appeals to a lot of builders and DIYers as although it is relatively cheap and budget-friendly, plywood still offers high levels of strength and durability. Thanks to its incredibly lightweight structure, plywood is much easier to transport meaning transportation costs are kept to a minimum. Additionally, as plywood can be utilised in a wide variety of projects, you can keep using it to significantly cut down on wastage.
4. Easy Installation
Another advantage to plywood is that it can be easily installed in a variety of applications, covering a multitude of area sizes. Standard plywood sheets are often available in much larger sizes with lengths of at least 1800mm and widths at 1200mm. Due to its wider size range, plywood provides enhanced square foot coverage which helps avoid wastage and uneven finishes as you can be sure you always have the right measurement of material for the job. Unlike solid wood, you can even use plywood to accommodate curved surfaces with no risk of snapping, warping or damage.
Even though plywood is a man-made product you can still be sure that is still offers fantastic benefits for the environment also. Although plywood does incorporate the use of wood, the manufacturing of one sheet requires much less wood usage than solid wood. A reduced amount of timber is utilised in the process with less wastage produced.
What Are the Disadvantages of Plywood?
Like with any building material, plywood does come with a few disadvantages to consider before using it in your project. Even though you will probably find the pros heavily outweigh the cons, it is important to understand the full picture before using this material.
- Pricier than MDF – Even though plywood itself is still very affordable, it can still be a more expensive material than medium density fibreboard.
- Damages – Although its lightweight structure means it is much easier to transport, this also does impose a higher risk of it being damaged during transportation which is something to keep in mind.
- Moisture Exposure – Most types of plywood should not generally be exposed to water or moisture for extended periods of time as this can cause damage to its structure. Can water ruin plywood?
- Cutting – Plywood can be more difficult to cut than MDF in some instances.
- Quality – It can sometimes be more difficult to judge the level of quality at which the plywood has been manufactured.
What Can Plywood be Used For?
Due to its properties, plywood can be utilised in a multitude of different large construction and smaller DIY projects. Before using this material, you will need to ensure that you use the appropriate thickness of plywood and that is has been correctly graded for your application. Plywood typically complies with specified British Standards so it can be useful to ask your timber merchant whether it is suitable for your job.
Types of Plywood
Structural plywood is specially designed and manufactured for use in permanent structural applications. This high-strength form of plywood is highly durable plus is fully resistant to weathering and can withstand higher levels of stress and weight. It is ideal for:
- Shipping crates
- Roof bracing
- Outdoor furniture
- Truck bodies
- Storage decks
The factor the separates exterior plywood from other forms is the use of water-resistant glue. Although not restricted to, exterior plywood is generally used for outdoor usage with its water-resistant properties. It is the most common bonding type of plywood available and is typically used for:
- Outdoor floorings
- Countertops around sinks
- Roof linings
Interior plywood is mainly for used for its aesthetic appearance in internal applications. It is not suitable for exposure to damp and wet conditions as the structure is not durable enough to withstand this. This type of plywood is perfect for:
- Wall linings
- Indoor furniture
- Interior cladding
- Decorative purposes
Close in design to exterior plywood, marine plywood is a high-strength durable material with a high-stress grade. The difference, however, is that the binder used in the marine alternative is specially formulated for water submersion which makes it fully resistant to rot in places subject to high levels of moisture. Marine plywood is suitable for use on:
- Lake platforms
- Bathroom/kitchen walls
Where Can I Buy Plywood?
Plywood sheets are available in a variety of DIY shops and online stores with a range of different sizes available. Here at Roofing Megastore, we offer a high-quality selection of conveniently sized plywood sheets in a practical choice of thicknesses.
When you are buying plywood sheets online or offline, ensure you read all the relevant information. This includes the origins of the wood, any certificates it has (or has not) received and whether it meets the specifications of relevant British Standards.
Have More Questions About Plywood?
If you have more questions about plywood sheets get in contact by calling on 01295 565 565 or drop us a message using our handy live chat.