Grading Definitions

Tilling Timber’s Architectural range of solid timber lining and cladding profiles are renowned for their premium quality. This comes from both the material used, and our production process. Please see below for details of our source material grading, and the types of finished product grading we manufacture.

Western Red Cedar

Bulk sawn timber is imported for manufacturing all our Western Red Cedar products. We only import No. 2 Clear and Better graded product, which is described as…

“Sound timber, well manufactured. Three (3) irregularities permitted on face side, four (4) on reverse side including corresponding half of edge or equivalent, for each 12 lineal feet (3.7m) of product, based on 8” (203mm) widths. Shall average at least six (6) rings of annual growth to the inch (25mm) on either one end or the other of the piece.”

Up to 15% of the cedar we receive may contain four (4) irregularities as described below on the face side and characteristic soft knots may extend into the opposite face.

From this source material, we then manufacture ‘Premium’ and ‘Mill Run’ grades of finished product. The table below details what natural features are allowed in our Western Red Cedar finished product grades.

Natural Feature Extent/Limitations Premium Mill Run
Variation in sawing Slight in occasional pieces Removed Present
Sound and tight knots 13mm on face side and 19mm on reverse side for boards under 76mm thick Present

(up to 3 per 3.7m)

Soft knots Only on reverse side and corresponding half of edges (approx. ½ the allowable size for sound tight knots) Removed Present
Splits Approximately the width of piece Removed Present
Grain Slope No more than 1 in 8 Present Present
Grain Width Average 6 rings per 25mm Present Present

Tasmanian Oak

Sawn boards are purchased from Neville Smith Forrest Products for manufacturing all our Tasmanian Oak products. We only purchase Select graded product, which is described as…

“… the most uniform in appearance, with minimal amounts of natural feature such as gum, natural stains and knots. Timber is generally graded on all faces. Tasmanian Oak is usually sold free of sapwood. Burl or hobnail feature may be present, as there is no limitation on them in any of the grades. None of the grades contain timber with decay, compression failures, shakes, splits or other fractures. Want, wane and mechanical damage are permitted only on concealed surfaces. A pack of timber of a particular grade will have a fair distribution of boards with the amount of feature allowed in that grade.”*

From this source material, we then manufacture ‘Select’ grades of finished product. The table below details what natural features are allowed in our finished Tasmanian Oak products.

Natural Feature Extent/Limitations
Natural stain or discolouration Slight.
Other discolouration Small amount may be present
Quartersawn tight gum vein Individual tight gum veins may be up to 2mm wide and 250mm in length. Aggregate length of all tight gum veins present is less than half of the board length.
Backsawn tight gum vein As for quartersawn tight gum vein
Loose gum vein Not present.
Gum & latex pockets, overgrowth of injury Not present.
Holes Small holes up to 2mm in diameter may be present. The maximum number of holes varies with the board width. For boards between 50 and 100mm wide, 5 holes are allowed in any 100mm with a total of 10 holes allowed in any 900mm length. For boards wider than 100mm, 8 holes are allowed in any 100mm length with a total of 16 holes allowed in any 900mm length.
Tight knots Tight knots may be present, but they must be smaller in aggregate than 15mm measured across their largest dimension, or ¼ of the surface width for any 1m of board length.
Checks appearing on the surface Small checks may be present, but they will each be less than 1mm wide and 250mm long


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