Engineered Wood
Engineered wood products are manufactured by binding wood strands, fibers, veneers, or boards with adhesives to create composite materials that offer improved dimensional stability, strength, and resource efficiency compared to solid wood.
Composition
Manufactured from wood veneers, strands, fibers, or particles bonded together with adhesives under heat and pressure. The specific composition varies by product type, with different arrangements of wood elements and binding agents.
Properties
Density (Plywood)
30-42 lbs/ft³
Varies by wood species and manufacturing process, with hardwood plywood typically denser than softwood plywood.
Density (OSB)
38-47 lbs/ft³
Generally denser than plywood, contributing to its strength and weight.
Bending Strength (Plywood)
3,000-7,000 psi
Varies by grade, species, and thickness, with higher grades offering greater strength.
Bending Strength (LVL)
2,600-3,000 psi
Higher than solid lumber of similar dimensions, making it suitable for long spans.
Dimensional Stability
High
Less prone to warping, twisting, and shrinking compared to solid wood due to cross-laminated construction.
Moisture Resistance
Varies by product
Exterior-grade products offer good moisture resistance, while interior grades require protection from moisture.
Applications
Structural Sheathing
Plywood and OSB are commonly used for roof, wall, and floor sheathing in residential and commercial construction, providing structural support and a nailing surface.
Beams and Headers
LVL, glulam, and PSL are used for load-bearing beams, headers over openings, and other structural applications requiring high strength and dimensional stability.
Flooring Substrate
Plywood and OSB serve as subflooring materials, providing a stable base for finish flooring materials like hardwood, tile, or carpet.
Furniture and Cabinetry
Higher-grade plywood, particleboard, and MDF are used in furniture manufacturing and cabinetry due to their stability and smooth surface.
Concrete Formwork
Specially treated plywood is used to create forms for concrete pouring, offering reusability and smooth concrete finishes.
Mass Timber Construction
Cross-laminated timber (CLT) and other engineered wood products are increasingly used in mid-rise and high-rise construction as an alternative to concrete and steel.
Advantages
- Efficient use of wood resources, utilizing smaller trees and wood waste
- Greater dimensional stability than solid wood, with reduced warping and shrinking
- Consistent quality and performance compared to natural wood
- Available in larger dimensions than solid wood
- Higher strength-to-weight ratio than many traditional building materials
- Can be manufactured to specific performance requirements
- Often more cost-effective than solid wood for large structural members
- Many types are available with sustainable forestry certifications
Limitations
- Some products contain formaldehyde-based adhesives that may off-gas
- Generally more susceptible to moisture damage than solid wood if not properly protected
- Higher embodied energy than solid wood due to manufacturing processes
- Some types (particularly OSB) can be difficult to repair if damaged
- May have lower fire resistance than solid wood of equivalent thickness
- Cutting and machining can be more difficult than with solid wood
- Some products may not accept finishes as well as solid wood
- End-of-life recycling can be challenging due to adhesives
Sustainability Profile
Moderate to high sustainability profile, depending on specific product and manufacturing processes. Engineered wood makes efficient use of forest resources, often utilizing fast-growing species and wood waste that might otherwise be discarded. Many products are available with FSC or PEFC certification ensuring responsible forestry practices. The primary environmental concerns include energy use in manufacturing and formaldehyde emissions from some adhesives, though low-emission and bio-based adhesives are increasingly available. Carbon sequestration benefits are significant, particularly for mass timber products used in place of concrete or steel.