Plywood

The main types of plywood

When using plywood structurally, ensure you specify plywood listed in code BS 5268-2:2002.

This can be sourced from Finland, Sweden, America or Canada, although Nordic plywood (mainly Finnish) is the UK’s predominant supply. It provides exceptional uniformity and quality and is backed by constant research.

There are many other types of plywood available, including specialist tropical veneers such as marine plywood, which, while having good weather resistance and strength, comply with specific standards such as BS 1088, rather than the structural standard code.

Birch:

Strong, with high impact resistance and an attractive decorative appearance. Available in a number of factory finishes, birch plywood is particularly suitable for visible surfaces, for wall and floor structures, furniture etc. as well as formwork.

Spruce:

Less dense than birch, spruce is lightweight and easy to nail, with good strength and stiffness properties, it is particularly suitable for walls, flooring and roof construction, vehicle construction, packing etc.

Thickness

Some standard panel sizes:

1220mm x 2440mm
1220mm x 3050mm
1220mm x 3660mm

Grades

Birch:

Grade B clean face, few blemishes, suitable for clear finishing where visual appearance is important.
Grade S similar to B but has more small knots and darker streaks. Grade BB standard commercial grade; sound but face can contain plugs and patches. For general construction.
Grade WG good board but more face defects. For carcassing and packing cases where strength, rather than appearance, is needed.

Spruce:

Grade 11/111 faces have large knots, and various allowable repairs. Suitable for wall and roof sheathing where visual appearance is not so important.
Grade 111/111 both sides as the grade 111 side, suitable for floors, sheathing and general building work.

Plywood for concreting

Spruce ply is ideal because of its strength and rigidity. It is available with a phenolic film surface, allowing repeated use for shuttering and formwork

Thicknesses from 6.5mm - 27mm
Widths from 1200mm - 3050mm
Lengths from 2400mm - 3600mm

Plywood for packaging

Plywood provides quality protection for products. Spruce is most commonly used for packaging as its light weight helps reduce overall transport costs.

It can be made into durable crates and protective panels. It is safe and clean to use for the food industry, environmentally-friendly and can be specially coated for flight cases etc.

Speciality plywoods

Craft plywoods: a variety of qualities; thicknesses 4mm - 12mm

Quality 1: thin veneers for aeroplanes etc.

Quality 2: thin birch for boats, musical instruments, models etc.

Quality 3: thin birch for surfaces that will be painted or lacquered; toys, models, shaped objects, sports gear, caravans.

Just because it’s CE marked doesn’t mean you’re covered.

The Construction Products Directive requires that all construction products bear the CE marking before being placed on the market. CE marking shows that the product complies with all necessary legal requirements and will, in principle, allow the product to be placed on the entire EEA (European Economic Area) construction market.

When specifying plywood for structural load bearing applications such as floors, walls and roofs, reference should be made to BS5268-2:2002. By following the recommendations of this standard, compliance with the structural adequacy aspects of the UK Building Regulations can be achieved.

For further information on a wide range of structural plywoods, both CE-marked and listed in BS 5268-2:2002, all using environmentally-friendly timber from sustainable forests. Please visit the links below:

Why CE Marking on WISA special plywoods for construction UPM-Kymmene WISA Plywood click here

Information about FinnForest plywoods and stockists click here

Learn more from the Plywood module in wood for good’s Online Learning. It’s free to architects, specifiers, members of the TTF and wood for good. To register free click here