LSL (Laminated Strand Lumber) Studs and Headers (2026)
Laminated Strand Lumber (LSL) is an engineered wood product manufactured from flaked wood strands oriented parallel to the length of the member, bonded with exterior-grade adhesives. It is categorized as a Structural Composite Lumber (SCL) under ASTM D5456 and is commonly used for high-load applications like headers, tall-wall studs, and rim joists.
Key Features
- High dimensional stability with minimal shrinkage or bowing
- Predictable structural values (E-modulus and bending strength)
- Available in long lengths up to 48 feet
- High fastener holding strength compared to sawn lumber
- Uniform strength properties throughout the member
Specifications
Applications
- Tall-wall framing studs (e.g.
- 2-story entryways)
- Door and window headers
- Floor joists and rim board
- Sill plates and columns
- Hip and valley rafters
Installation Overview
- Use standard wood-framing tools; carbide-tipped blades are recommended due to adhesive hardness.
- Fastening should follow the manufacturer's specific nailing schedule; pre-drilling may be required to avoid splitting if nailing close to the edge.
- Keep LSL dry; it is not intended for permanent exposure to moisture or soil contact.
- Headers must be supported by adequate jack studs and king studs based on local load path requirements.
Pros & Cons
Pros
- ✓ Excellent resistance to warping
- ✓ twisting
- ✓ and crowning
- ✓ Superior load-bearing capacity over standard dimension lumber
- ✓ Consistent quality with no large knots or structural voids
Cons
- ✗ Heavier than comparable dimension lumber
- ✗ Higher cost per board foot compared to Douglas Fir-Larch
- ✗ Excessive tool wear on saw blades and drill bits
- ✗ Not suitable for direct soil or ground contact
Code Requirements
- Must be installed in accordance with ICC-ES evaluation reports.
- Comply with International Residential Code (IRC) Section R502.8 for cutouts and notches.
- Must meet ASTM D5456 performance standards for structural composite lumber.
- Design values must be verified via the manufacturer's ICC-ES evaluation report.
Buying Tips
- Verify the specific grade or 'E-rating' matches your engineer's load calculation.
- Ensure the product is marked with an NDS (National Design Specification) code reference.
- Check moisture content upon delivery; even though LSL is stable, it should not be installed if saturated.
- Order specific lengths to reduce on-site waste, as LSL is available in custom-length increments.