Plywood: What Is It and How Is It Used?
A high-quality engineered wood, plywood is used in everything from houses to furniture and even boats, coming in a wide range of grades and finishes. In this overview from Building Materials Nationwide, we’ll cover the essentials of plywood, how it’s made, the benefits and drawbacks, the products available, and their common uses. Plywood is a popular choice among professional builders and DIYers alike, with great strength and a competitive price point.
What is Plywood?
Plywood is an engineered wood product that is commonly used across the UK. It is constructed from multiple layers of veneer, essentially very thin sheets of wood, which will be bonded to each other with resin adhesive and cured with heat and pressure. The sheets themselves will be placed so the grain is a 90-degree rotation on each layer, which helps to add strength. In a lot of cases, the veneer of the outer facing or facings will be of a higher grade, in order to give the plywood a nicer appearance.
What Are the Benefits of Plywood?
Plywood has become a popular product for both professionals and DIYers alike, bringing a series of benefits with it.
- Wide Variety of Sizes: Compared to real wood products plywood can be made in a wide variety of sizes and thicknesses, aiding its use in many different building projects.
- Strength: Plywood is amongst the strongest engineered woods, and while it can’t quite match graded timber, this means that it can be used within more strength-based applications than products like MDF. This strength is due to the adjacent layers of real wood making up its construction.
- Range of Types on Sale: Plywood has different grades and types on sale, allowing you to choose a specific product tailored to your needs. As we’ll explain later, these options are one of the key reasons for plywoods' popularity.
- Easy to Nail and Screw: The strength of plywood and the structure of its veneers means that it holds nails and screws well, offing clear benefits within construction. Other engineered woods can have issues with splitting when nailed.
- Bendable: Certain plywood types can be bent, bringing benefits to both small and large constructions like ramps and curved items.
- Lighter Than Wood: Another benefit for construction, plywood has a comparatively low weight. It is lighter than MDF, a competing engineered wood product.
- Lower Cost: Plywood is an affordable building material compared to timber, a key reason for its popularity.
Are There Any Drawbacks to Plywood?
While plywood has remained a hugely popular building material for over 100 years due to its clear benefits, there are some drawbacks worth bearing in mind when deciding on the best materials for a project.
- Difficulty Decorating: Plywood is often rough, making it difficult to paint. Sanding it down can cause issues with splintering and chipping layers. This means that plywood is not always the ideal engineered wood to use as surfacing, compared to a product like MDF, which has a flat, smooth appearance, and is easy to paint.
- Issues With Moisture: While there are moisture-resistant options, most types of plywood will absorb moisture over time, causing damage to the plywood and weakening the bonds between veneers.
- Issues With Emissions: The adhesives used within plywood can release dangerous gases when sawn. As such, you should only cut plywood within a well-ventilated area, wearing full safety gear including a gas mask and protective glasses. You should thoroughly clean all surfaces afterwards.
- Difficulty Sawing: Due to its structure there can be issues sawing plywood, creating rough edges and splintering. You’ll have to use specific tools and techniques to cleanly cut plywood panels. Compared to MDF which can be easily cut to size, plywood can be a more complex process.
What Types of Plywood Are Available in the UK?
When shopping for plywood within the UK you’ll have a suite of options, built from different veneers or using different adhesives to offer specific properties and benefits. It’s vital that you buy a plywood type suited to your needs.
Structural Plywood
Structural plywood sheets will need to meet certain standards for strength and durability. The main difference between structural plywood and general-purpose models is the type of adhesive used for bonding the veneers together. For strength-based uses within a building, it’s important to use a type of plywood designed for such performance.
- Hardwood Throughout Plywood 2440mm x 1220mm | 2.98m2 (500/002/10301)
2 - 3 WORKING DAY DELIVERY
- 2440mm x 1220mm
- 8' x 4'
- Hardwood Faced Plywood 2440mm x 1220mm | 2.98m2 (053/124/1119)
2 - 3 WORKING DAY DELIVERY
- 8ft x 4ft
- 2440mm x 1220mm
Marine Plywood
Marine plywood is designed with water-resistant properties in mind. While not wholly waterproof, it uses waterproof glue to ensure high levels of resistance to moisture and water. Marine plywood is also strong and largely free of defects. It will be commonly used for external applications, and can also be used within boats.
- Marine Plywood 2440mm x 1220mm | 2.98m2 (053/125/1121)
2 - 3 WORKING DAY DELIVERY
- 8ft x 4ft
- Moisture resistant
Flexible Plywood
While some plywood types can be bent over time, flexible plywood is designed to easily bend, for a wide variety of curved applications. This is achieved by lining up the grain of each veneer, which allows it to be bent easily, giving a clean, attractive look. A flexible plywood panel that will bend along the longer edge is called cross-grain plywood, whereas a panel that will bend along the short edge is long-grain plywood.
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2 - 3 WORKING DAY DELIVERY
- 8ft x 4ft
- Allow 24hrs to acclimatize
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2 - 3 WORKING DAY DELIVERY
- 8ft x 4ft
- Allow 24hrs to acclimatize
Softwood Plywood
Softwood plywood will be faced with, and typically made from, softwood veneers from trees like cedar, douglas fir, and pine. This will typically be used for building and formwork applications and is rarely used visually.
- Softwood CDX Plywood 2440mm x 1220mm | 2.98m2 (053/124/1118)
2 - 3 WORKING DAY DELIVERY
- 8ft x 4ft
- CDX almost 10% stronger than OSB
Hardwood Plywood
Hardwood plywood will offer a greater level of strength, making it suitable for more heavy-duty uses, alongside visible uses like furniture and panelling. It is also often used for the making of instruments. Options would include birch plywood.
- Hardwood Faced Plywood 2440mm x 1220mm | 2.98m2 (053/124/1119)
2 - 3 WORKING DAY DELIVERY
- 8ft x 4ft
- 2440mm x 1220mm
- Hardwood Throughout Plywood 2440mm x 1220mm | 2.98m2 (500/002/10301)
2 - 3 WORKING DAY DELIVERY
- 2440mm x 1220mm
- 8' x 4'
Insulated Plywood
Insulated plywood panels consist of an insulated foam core glued between two layers of plywood. These panels, called SIPs (Structurally insulated panels) offer a structurally sound form of insulation for homes, walls, ceilings, and floors.
- Warmline PIR Insulated Plywood 2400mm x 1200mm (200/013/03412)
2 - 3 WORKING DAY DELIVERY
- 8ft x 4ft
- 6mm Plywood Backing
Shuttering Plywood
The cheapest plywood available, shuttering plywood is used for temporary building uses, such as covering up broken windows or as formwork for concrete pours. It will be of a low quality visually, with defects, but serves several important purposes.
How is Plywood Graded?
Within the UK, plywood will be graded as one of three categories for its moisture performance, based on the timber and adhesives used in construction.
Grade | Meaning |
Class I | Suitable for dry interior use |
Class II | Suitable for humid interior environments like kitchens and bathrooms, and for occasional water contact |
Class III | Suitable for exterior use and frequent water contact. |
There will also be visual grading options for plywood, allowing you to pick options suitable for visual usage and others that would be better used structurally.
Grading | Meaning |
AB | Consistent surface, typically the best quality. Some small pin knots but no bigger than a few mm. |
B | Less consistent, with changes in colour and wood grain. Some smooth knots. |
BR Veneer | Similar to B grade but with smaller knots. |
BB | Similar to B but allowing larger knots, better suited for non-aesthetic uses. |
C | Used for strength based applications. Visible discolouring, splits, and knots. Not used for visual applications. |
CC | Splits, open knots and discolouring. Used for non-visual applications. |
What is Plywood Used For Within a Building Project?
Plywood is used throughout both the construction and furniture industries when quality engineered wood is called for. The different gradings and types available offer further benefits within a variety of applications.
Furniture
The strength and attractive grain of quality plywood allow it to be used to make an array of quality furniture items. Everything from tables, chairs, storage units, display cases, and bedframes can be produced from sheets of plywood. You can also use sheets of plywood with moisture-resistant properties, such as marine plywood, to construct external furniture items like doghouses.
Roofing
Roof decking, sometimes called sheathing, is the underside of your roof that is connected to your house, on which the shingles will be hung. The strength of plywood makes it a great choice, and its superior water performance compared to other engineered woods like MDF will also benefit due to the risks of dampness within a roof. As this is a non-visible use, you can use a lower-grade model, with knots and splits, though strength should still be prioritised.
Flooring
Plywood has traditionally been used as an underlay for other flooring materials, but it can also be used as an affordable flooring by itself. For an underlay, you’ll be looking to use interlocking plywood sheets to create a steady base, onto which carpeting, laminate, or authentic hardwood can be fitted. For the flooring itself, plywood boards with a high visual grading can be cut to size and easily installed like traditional floorboards. This will be more cost-effective than traditional hardwood flooring, but the downside is that plywood gets scratched more easily. Depending on the room you’re installing your plywood flooring in, you may also need to opt for a water-resistant option.
Wall Framing
Plywood can be used as a wall framing and can be covered or left exposed, much like a floor. Plywood offers good durability and natural acoustic properties. Stained high-grade plywood sheets can be cut to size and used for a sleek modern look, or alternatively, structural plywood can be used as a cladding base for other wall coverings. For wall framing, using fire-resistant plywood can be beneficial, slowing the progression of flames in the event of a fire.
Boats and Docks
While it has other uses in exterior locations or areas at high moisture risk, marine plywood is named as such due to its common use in boats and docks. Due to its resistance to rot and moisture, marine plywood is popularly used in boat construction. It’s worth bearing in mind that any boat made with marine plywood will need to be sealed before it is seaworthy. Marine plywood is also used as a cost-effective and low-maintenance choice for docks, due to its quality performance in the water.
Is Plywood Waterproof?
In its standard form plywood is not suitable for use in water. Over an extended period, it can start to swell and change shape. Water can also lead to the boards splitting apart as it degrades the adhesives between each veneer. There are specialist plywood types available with water resistance, and you can also coat a regular plywood board with sealants to make it water-resistant. Waterproofing is not a term that is commonly used within the industry, as it can be considered misleading.
Is Plywood Fireproof?
Regular plywood is a combustible material, as it is made from many layers of wood joined together. There are fire-resistant options available for sale, which will be pressure treated and infused with fire-retardant chemicals, and also further sprayed with them. This can slow the spread of fire through a plywood-based construction.
Is Plywood Sustainable?
Providing that the wood from which it is sourced is sustainably grown, then the plywood made from their veneers will also be sustainable. Plywood requires relatively little energy to be produced, and can itself be recycled. It has a comparatively long lifespan compared to other engineered woods like MDF.
How Big Are Sheets of Plywood?
Plywood can be cut into many sizes, but the standard sizing will be either 2400mm x 1200mm or 2440mm x 1220mm. These sheets will come in a range of thicknesses, for instance, our Softwood CDF plywood boards come in 9mm, 12mm, 18mm, and 24mm thicknesses.
How to Cut Plywood
There can be issues when cutting plywood, with tears forming between layers giving a rough, unprofessional look. You should look to use a blade specifically tailored to plywood regardless of if you are using a table saw a circular saw, or a hand saw. Sharpness is also vital, to limit the risk of tearing.
You should be careful to take personal safety precautions when cutting plywood. The adhesives used to bond sheets of veneer within plywood can release dangerous dust when cut. As such, you should only cut plywood within a well-ventilated space, using full protective gear with a gas mask and safety goggles. If possible, cut outside, but if not carefully clean and hoover all dust afterwards.
How Can Plywood Be Decorated?
Plywoods of a higher grade are suitable for all types of visual usage within either a building or a piece of furniture. It can therefore be finished visually, with painting and staining being the two main options available to you. Staining will keep the natural beauty of the wood, especially relevant in high-grade hardwood plywood, with fetching colour and grain. You’ll need to use sandpaper to smooth out the surface before applying stain, repeating the process to give a fantastic look that can be used for panelling or furniture work.
Painting plywood is a more fraught proposition but is possible. You’ll also need to sand your plywood down to an even smooth surface. You’ll then need to use a plywood primer as an undercoat. Afterwards, you can paint two or more coats of acrylic latex paint or an oil-based paint intended for plywood, sanding again between each coat.
Our Range of Plywood Products For Sale
At Building Materials Nationwide, we stock a wide selection of plywood for sale, featuring softwood, hardwood, and marine plywood options. All of our product range can be delivered across the UK, perfect for both professional and DIY projects. We work with customers throughout the industry, offering trade accounts with a wide range of benefits. Our trade account holders gain access to our supplier network, our fast delivery options, and the services of a dedicated account manager. Sign up for a trade account through our website today.