Principles to minimise potential problems with Class 2 and Class 3 off form Surface Finishes,F17 FORMPLY TECHNICAL ,formwork plywood inspection,graders checklist, AS 6669 Plywood sourcing service,phenolic surface film Testing

Principles to minimise potential problems with Class
2 and Class 3 off form Surface Finishes
Principle One: Most issues with off form surface finishes are associated with moisture.
Wherever possible protect the formwork from weather. This includes
tarping where practical.
Principle Two: The phenolic surface film used on formwork plywood is not impermeable
to moisture. To ensure that moisture penetration is minimised, release
agent and form oils must be used. Form oils and release agents assist in
minimising moisture penetration where the phenolic surface film has
been damaged.
Principle Three: Plywood must be supplied to the jobsite flat. Any sheets showing bow or
twist greater than 30mm should be returned to the manufacturer.
Principle Four: Where flat plywood has been supplied, the formwork is responsible for
any distortion following installation. Decks must be inspected prior to
pouring and any distorted sheets likely to cause surface imperfections
nailed and screwed flat.
Sheets must be positively fixed. It is not adequate to rely on the weight
of the concrete to flatten distorted formwork plywood sheets.
Principle Five: Where severe weather exposure is expected i.e. summer months,
consideration should be given to using thicker plywood with a heavier
grade of phenolic surface film and a thinner face veneer. This will
minimise both distortion and grain raising.
For further advice, please feel free to contact the Engineered Wood Products Association
of Australasia directly on +61 7 3250 3700 or www.ewp.asn.au.