Laminated veneer lumber (LVL)
LVL, laminated veneer lumber: LVL-P and LVL-C, strength classes (LVL 32–80 P), common sizes, standard and uses as beams and panels.
German: Furnierschichtholz
A material glued from many thin rotary-cut veneers, about 3 mm thick, mostly with the grain in the same direction. Thanks to the thin layers it is very uniform and strong, with outstanding load-bearing capacity in one direction.
How is it made?
Thin veneer is peeled from the log, and the veneers are glued on top of each other layer by layer with MUF or PF adhesive. In LVL-P all veneers are parallel; LVL-C also has at least two cross veneers – which improves dimensional stability and load-bearing capacity in the cross direction. Several LVL panels can be glued together into thicker members (GLVL).
In 2020, European manufacturers introduced strength classes (LVL 32 P – LVL 80 P), which are being adopted in the revision of EN 14374. LVL leaves the factory with 8–10% moisture.
Technical data
- Build-up
- rotary-cut veneers approx. 3 mm thick: parallel only (LVL-P) or with some cross veneers (LVL-C)
- Raw material
- spruce, pine, Douglas fir, beech
- Strength
- classes LVL 32 P – LVL 80 P: bending strength (flatwise) 32–80 N/mm²
- Density
- 440–800 kg/m³ (from softwood to beech)
- Adhesive
- MUF or PF
- Common sizes
- thickness approx. 15–75 mm, panels up to 2.5 m wide, length up to 24 m; beams are cut from the panels
- Standard
- EN 14374
- What is it for?
- high-strength beams, columns, truss chords, floor and wall elements
| Type | Thickness (mm) | Width | Length |
|---|---|---|---|
| panel (LVL-P or LVL-C) | approx. 15–75 | 1.8–2.5 m | up to 24 m |
| beam (cut from the panel) | approx. 27–75 | from 40 mm | up to 24 m |
Based on a retailer’s product data; sizes vary between manufacturers.
Applications
- heavily loaded, slender beams, columns and lintels
- truss chords, load-bearing structures of large halls
- as panels (LVL-C): wall and floor elements, diaphragms
- flanges of timber I-joists
What to watch out for
- LVL-P, with parallel veneers only, is weaker in the cross direction – for panels and diaphragms, LVL-C with cross veneers is the right choice.
- Beech LVL is much stronger than spruce (hardwood is one and a half to three times stronger), allowing more slender structures, but it is also heavier.
- The classes are still new; the design must be based on the declaration of performance of the specific product.