WISA-Form Birch is a coated special plywood for use in concrete formwork where high requirements are set on the concrete surface and the number of reuses.
Base board: Birch plywood made solely from birch (hardwood) veneers bonded together in a cross banded construction.
Bonding: Phenolic resin cross-bonded weather resistant glueing according to EN 314-2/class 3.
Surface and edges: Face and reverse – Dark brown phenolic film 120 g/m2 or 220 g/m2 moisture barrier. Edge sealing – water resistant paint.
Panel size: Standard panel sizes – 1200/1220/1250/1500/1525 x 2400/2440/2500/2700/3000/3050/3600/3660mm
Cut sizes at customer’s request
Size tolerance (length/width) ±1mm per metre
Squareness tolerance ±1mm per metre length of diagonal
Reuses: Typical number of reuses is likely to be in the range of 20 – 80 times. However, this will vary according to many different factors including good site practice, required concrete finish, amount of care taken when compacting the concrete, handling and storage of the forms, type and quality of release agent.