OSB-3 Structural Subfloor & Sheathing Panels are high-load engineered oriented strand boards manufactured under EN 300 Class OSB/3 and OSB/4. Made from debarked pine strands cross-oriented in perpendicular layers and bonded with 100% formaldehyde-free waterproof MDI resin, they deliver superior bending strength (MOR ≥ 22 N/mm²), zero internal voids or core gaps, and severe humidity resistance for timber-frame roof sheathing, wall bracing, and subfloors.
Cross-Oriented Strand Architecture & pMDI Resin
Manufactured from debarked, fresh Scots pine logs, wood strands (80–120mm length, 0.6mm thickness) are mechanically aligned into 3 engineered layers: surface strands run longitudinally along the length for maximum bending stiffness, while core strands run perpendicularly (90° cross-ply):
Panel Structure, Processing & Applications
Explore panel surfaces, core structures, processing and applications.
1. Oriented Wood Strands
2. Tongue-and-Groove Joint
3. Mezzanine Flooring
4. Pallet Packing
OSB/3 & OSB/4 Engineering Technical Data Sheet
Certified mechanical values across thicknesses under EN 300 for structural Service Class 1 and Service Class 2 building codes.
| Physical & Mechanical Property | Testing Standard | Units | 9 mm – 10 mm | >10 mm – 18 mm (18mm) | >18 mm – 25 mm (22mm) |
|---|---|---|---|---|---|
| Nominal Density | EN 323 | kg/m³ | 610 – 640 | 600 – 630 | 590 – 620 |
| Bending Strength MOR (Major Axis) | EN 310 | N/mm² | ≥ 22.0 (Cuzi: 25.0) | ≥ 20.0 (Cuzi: 24.5) | ≥ 18.0 (Cuzi: 22.0) |
| Bending Strength MOR (Minor Axis) | EN 310 | N/mm² | ≥ 11.0 (Cuzi: 13.0) | ≥ 10.0 (Cuzi: 12.5) | ≥ 9.0 (Cuzi: 11.0) |
| Modulus of Elasticity MOE (Major Axis) | EN 310 | N/mm² | ≥ 3500 (Cuzi: 4200) | ≥ 3500 (Cuzi: 4100) | ≥ 3500 (Cuzi: 3900) |
| Modulus of Elasticity MOE (Minor Axis) | EN 310 | N/mm² | ≥ 1400 (Cuzi: 1800) | ≥ 1400 (Cuzi: 1750) | ≥ 1400 (Cuzi: 1650) |
| Internal Bond Strength (IB) | EN 319 | N/mm² | ≥ 0.34 (Cuzi: 0.48) | ≥ 0.32 (Cuzi: 0.45) | ≥ 0.30 (Cuzi: 0.42) |
| 24-Hour Thickness Swelling (OSB/3) | EN 317 | % | ≤ 15.0% (Cuzi: 11.5%) | ≤ 15.0% (Cuzi: 11.0%) | ≤ 15.0% (Cuzi: 10.8%) |
| 24-Hour Thickness Swelling (OSB/4) | EN 317 | % | ≤ 12.0% (Cuzi: 9.0%) | ≤ 12.0% (Cuzi: 8.8%) | ≤ 12.0% (Cuzi: 8.5%) |
| Formaldehyde Emission | ASTM E1333 / EN 717-1 | ppm | NAF / < 0.01 ppm | NAF / < 0.01 ppm | NAF / < 0.01 ppm |
| Moisture Content | EN 322 | % | 5.0% – 9.0% | 5.0% – 9.0% | 5.0% – 9.0% |
1. Roof Decking & Wall Sheathing Guidelines
Engineering installation specifications for timber-frame residential and commercial construction:
- Roof Sheathing Spans: 11mm or 12mm OSB/3 spans rafter centers up to 600mm. Always lay panels with the major axis perpendicular to rafters.
- Expansion Gaps Mandatory: Leave a 3mm expansion gap at all butt joints and panel edges to prevent buckling during weather changes.
- Wall Shear Bracing: 9mm and 11mm OSB/3 panels provide seismic and high-wind racking resistance under IBC and Eurocode 5 standards.
- Fastener Specifications: Use 60mm hot-dip galvanized ring-shank nails at 150mm perimeter centers and 300mm field centers.
2. Interlocking T&G Subfloor Installation
Heavy-duty subflooring protocols for squeak-free residential and mezzanine floors:
- Joist Span Centers: 18mm OSB/3 on 400mm centers; 22mm OSB/3 on 600mm centers (supporting 5.0 kN/m² design live loads).
- Adhesive Tongue & Groove Bonding: Apply D4 polyurethane structural adhesive continuously along all T&G joints before driving panels together.
- Zero Core Voids: Unlike softwood CDX plywood, OSB contains no internal knotholes, eliminating weak soft spots under heavy concentrated foot traffic.
OSB/3 & OSB/4 Structural Panels FCL Container Loading Data
Pallet packing specifications for standard 4×8 ft (1220×2440 mm) and European metric (1250×2500 mm) sizes.
| Thickness | Standard Format | Sheets / Pallet | 20'GP Container (8 Pallets) | 40'HQ Container (16 Pallets) | Net Timber Volume (40'HQ) | Gross Weight (40'HQ) |
|---|---|---|---|---|---|---|
| 9 mm | 1220 × 2440 mm (4×8 ft) | 110 Sheets | 8 Pallets (880 Sheets) | 16 Pallets (1,760 Sheets) | 47.15 m³ | ~26.5 Metric Tons |
| 11 mm | 1220 × 2440 mm (4×8 ft) | 90 Sheets | 8 Pallets (720 Sheets) | 16 Pallets (1,440 Sheets) | 47.15 m³ | ~26.6 Metric Tons |
| 12 mm | 1220 × 2440 mm (4×8 ft) | 80 Sheets | 8 Pallets (640 Sheets) | 16 Pallets (1,280 Sheets) | 45.72 m³ | ~26.4 Metric Tons |
| 15 mm | 1220 × 2440 mm (4×8 ft) | 65 Sheets | 8 Pallets (520 Sheets) | 16 Pallets (1,040 Sheets) | 46.44 m³ | ~26.7 Metric Tons |
| 18 mm (High-Volume Subfloor) | 1220 × 2440 mm (4×8 ft) | 55 Sheets | 8 Pallets (440 Sheets) | 16 Pallets (880 Sheets) | 47.15 m³ | ~26.4 Metric Tons |
| 22 mm (Heavy T&G Deck) | 1220 × 2440 mm (4×8 ft) | 45 Sheets | 8 Pallets (360 Sheets) | 16 Pallets (720 Sheets) | 47.15 m³ | ~26.8 Metric Tons |
| 18 mm Metric | 1250 × 2500 mm (European) | 52 Sheets | — | 16 Pallets (832 Sheets) | 46.80 m³ | ~26.7 Metric Tons |