LVL Handbook EUROPE

2. LVL STRUCTURES IN FLOORS, WALLS, ROOFS AND IN SPECIAL APPLICATIONS

Lapwall, Metsä Wood

Stressed skin rib panels and box panels

For long-span roof elements, the composite action of glued

stressed-skin panels can be utilized between LVL-P ribs and

LVL-C panels. Rib panels can be used, e.g., for non-heated

shelters, and insulated box elements for hall constructions. De-

pending on the snow loads and height of the elements, span

lengths can be 10-20 metres.

The structure is simpler than elements with purlins as no

secondary beams or battens are needed. However, if the rib

spacing is large, up to 1250 mm, the top panel must be thick-

er because the main direction of the LVL-C is along the ribs,

and the panels need to transfer the snow load to the ribs in the

secondary direction.

Figure 2.41.

LVL box panel element.

The ceiling panel thickness depends on the fire resistance

requirements. Depending on the reaction to fire requirements

of the project, LVL-C bottom flange panels can be left visible or

covered with gypsumboard. A great advantage of box elements

is that suspension installations, such as ventilation channels,

can be freely fixed with screws anywhere on the ceiling sur-

face because the LVL-C panels provide a solid base for axially

loaded connections.

An LVL box element roof can be realized as a cold roof or

warm roof solution, but the building physics design needs to

be done separately based on the project-specific indoor and

outdoor conditions. Stressed-skin panels can be CE marked

based on the ETA assessments of the element suppliers

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LVL Handbook Europe