Plywood

What we supply

• Structural softwood plywoodGraded for roof decks, floors and sheathing.
• Exterior plywoodBonded for humid and exterior conditions.
• Shuttering plywoodEconomical ply for concrete formwork.
• Hardwood-faced plywoodSmoother faces for joinery and fit-out.
• Marine plywoodHigh-grade ply for very demanding conditions.
• Phenolic-faced plyHard-wearing film-faced sheets for floors and formwork.

Sizes and specifications

Sheet size	2440 × 1220 mm (8 × 4 ft)
Thicknesses	5.5, 9, 12, 18, 25 mm commonly
Standards	BS EN 636 (bond to BS EN 314-2); structural use to BS EN 13986

Sizes and standards are typical for the UK market; exact figures depend on the manufacturer and are confirmed on your quote.

Common uses

• Flat roof decks
• Floors over joists
• Formwork
• Joinery and fit-out

Choosing plywood

Interior or exterior?

BS EN 636 classes plywood as class 1 (dry), class 2 (humid) or class 3 (exterior). Use class 3 for anything exposed to the weather.

Structural use

Roof decks and floors need plywood marked for structural use. Check the thickness against the joist spacing.

Thickness for floors

18 mm or more is common for floors on joists at 400 mm centres; follow your design.

How it arrives on site

Sheets travel flat on the lorry bed and are hand-offloaded or crane-lifted in packs. We agree the drop point and offload method when we price your order. Read more about how delivery works.

How much do you need?

Decking 24 m² with 2440 × 1220 mm sheets takes 9 sheets including 10% for cutting.

Plywood: questions

What size is a sheet of plywood?

The standard sheet is 2440 × 1220 mm, also known as 8 × 4 feet.

What plywood should I use outside?

Use plywood with an exterior bond, class 3 under BS EN 636, or marine ply for very wet conditions.

What thickness for a flat roof deck?

18 mm structural ply is common on joists at 400 mm centres; your design may specify more.

Is shuttering ply suitable for building?

It is made for concrete formwork, not for permanent structural decks. Use structural ply for roofs and floors.

How many sheets of plywood do I need?

Divide the area by 2.98 m² (the area of an 8 × 4 sheet) and add about 10 percent for cutting.