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Grades for Face and Back Veneers

The wood used for concrete forming veneers must come from the strongest wood species.

  • Face veneers need to be at least grade B with the back veneer not less than grade C.
  • APA Structural 1 Plyform requires grade B veneers for face and back, and both from the same species group.
  • The minimum grade for inner plies has to be grade C.
  • The lower the grade of veneer, the greater the size and number of defects (such as knots and splits).  This reduces its strength and stiffness. A lower grade may be cheaper due to the defects permitted for that grade, but the specifier has to ensure that the strength and stiffness is sufficient for the building design.

The information is adapted from APA’s Concrete Forming Design/Construction Guide.

Concrete Plyform Panel Types  Veneer

Class 1

Class 2

(suitable for most standard applications)

Structural 1

option (i)

option (ii)

B-B B-C HDO MDO Veneer Species Group Minimum Grade Species Group Minimum Grade Species Group Minimum Grade Species Group Minimum Grade
Face 1a Bc sanded 1a or 2 Bcsanded 3asanded Bc sanded Min. 3.2mm (1/8”) veneer thickness before sanding1 1a Bc sanded
Cross Band 1 or 2 C 1,2, 3 or 4 C 1,2,3 C 1 C
Centre 1,2,3 or 4 C 1,2,3 or 4 C 1,2,3 or 4 C 1 C
Back 1a Ccsanded 1a or 2b Ccsanded 3asanded Cc sanded Min. 3.2mm (1/8”) veneer thickness before sanding1 1a Bc sanded

a refers to Western Larch excluded from all face veneers

b same species group as face veneer

c indicates that with this grade, there is a mill-applied release agent

 

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