CLT - Cross laminated timber
Production
The production method:
How PFEIFER CLT panels are made
SAWN TIMBER
Softwood is harvested in the forest and processed into panels at Pfeifer’s own sawmill.
DRYING
Softwood panels are first technically dried at a temperature of 55 ° C for 48 hours until they reach a moisture content of roughly 8 - 16 %. After that, they are pre-planed.
SORTING
The pre-planed and technically dried panels are then mechanically sorted by strength. If higher surface quality is required, special sorting criteria that go beyond mere strength-related factors are applied for the top element lamellas.
FINGER JOINTING & LAMELLA PLANING
Panel sections that have been found to contain strength-lowering or unpleasant growth deviations such as large branches, pitch pockets or bark inclusions during sorting are eliminated depending on the strength and surface quality class. Thanks to force-fitting finger jointing, the individual panels are joined to theoretically endless lamellas in longitudinal direction. The endless lamellas are then planed to the desired thickness.
BONDING
The lamellas are laid out flat and glued in plies.
PRESSING
The press force is applied by means of hydraulic presses. Pfeifer's press applies its pressure evenly across the entire surface to minimise gaps between the lamellas.
CUTTING
Cutting tasks may be required depending on the job. This can include format cuts, door and window cutouts, rabbets, holes, breakthroughs etc.
COSMETICS + SANDING (IN CASE OF REQUIREMENTS TOWARDS APPEARANCE)
The last stage includes a visual fine-tuning. This is when defects are patched using wood patches. After that the panels with special requirements towards appearance are sanded using a sanding system.