What sizes do plywood sheets come in?

Common boards are 2440×1220 mm (8×4), and Ply Direct can cut to any size you need. Thickness typically ranges from 4–30 mm depending on the material.

How much does a ply sheet cost?

Prices vary by material, thickness and dimensions. Enter your sizes on the product page for a live price or request a quote.

Can I get plywood cut to size?

Yes. Ply Direct offers accurate cutting on professional equipment for clean, splinter-free edges.

How is plywood different from MDF?

Plywood is made from cross-layered veneers for strength and improved moisture performance, while MDF is compressed fibres. Plywood is generally stronger and more moisture resistant.

18mm Marine Plywood | BS 1088 Full Board

18mm marine plywood — BS 1088 full board for heavy-duty, wet-area builds

Pick 18mm marine plywood when you need maximum stiffness, reliable moisture resistance, and clean finishes. This full board uses durable hardwood veneers and waterproof bonding to meet BS 1088 requirements. Because the core has minimal voids and strong glue lines, the sheet stays flat, cuts neatly, and holds screws securely. As a result, 18mm marine plywood it excels in boatbuilding, bathroom and utility floors, coastal joinery, van decks, and outdoor furniture where thinner panels fall short.

Key benefits

18mm Plywood BS 1088 marine grade for consistent performance in humid conditions
18mm plywood ply thickness for floors, decks, benches, and structural liners
Smooth, sanded faces ready for varnish, paint, or laminate
Low-void core for crisp edges and solid fastener grip
High moisture resistance thanks to dense veneers and WBP bonding

Need parts ready to fit? Order Marine Plywood – Cut to Size.

Building non-slip floors or ramps? See Buffalo Board – Full Board.

For dry-area cabinetry, compare Birch Plywood – Full Board.

Typical uses

Use 18mm marine ply for:

Boat interiors and decks where strength and water resistance are essential
Bathrooms and utilities with appropriate waterproof finishes
Van and trailer decks with sealed edges and robust fixings
Garden rooms and coastal projects in sheltered exposures
Worktops, benches, and platforms that demand extra rigidity

Working & finishing tips

First, acclimatise boards to site conditions. Next, pre-seal all edges—especially cut edges—with a compatible sealer or varnish. Then pre-drill and fix at recommended centres, leaving small expansion gaps at walls and corners. Finally, apply a water-resistant finish; in shower or splash zones, pair the sheet with a waterproof membrane or liner for best results.

Quick specs

Grade: BS 1088 marine plywood
Thickness: 18 mm (full boards; cut-to-size available)
Faces: Smooth hardwood veneers
Bonding: Waterproof (WBP) adhesive

Frequently Asked Questions

1. Is 18mm marine plywood suitable for floors and decks?
Yes. 18mm marine ply is a common choice for boat floors, van decks, and structural liners. For extreme spans, add closer supports.

2. Can I paint or varnish it?
Absolutely. The faces are smooth and ready for varnish, paint, or laminate—seal edges first.

3. Is marine plywood fully waterproof?
No plywood is 100% waterproof, but BS 1088 18mm marine plywood is highly water-resistant. Proper finishing and maintenance are still essential.

4. Do you deliver nationwide?
Yes—order online for fast UK delivery. We also offer a cut-to-size service.