Birch

Sort А – At least 50% of the total amount should be the knotless material on 4 sides. Over the rest 50%, there should be allowed a couple of knots up to 20 mm in the saw face, at worst. There should not be allowed any discoloration, touchwood, marble touchwood, log blue, mildew, cracks, or end shakes, sweep, mechanical or any other defects, undersize, thwart marks, heartwood, or wane edge.

Sort AB – There should be allowed knots (or some other defects), which are at a distance of 50 cm at least. Between the knots (the defects), the knotless material should expose on 4 sides. Over 70% of the total length should, the knotless material should expose. There should not be allowed any discoloration, touchwood, marble touchwood, log blue, mildew, cracks, or end shakes.

Alder

One side is knotless. There should not be allowed any coloured stains, discoloration, knots, wane edge, mechanical defects, fault core, heartwood, log blue, or touchwood (meanwhile live knots up to 10 mm should be allowed). One-half of the board thickness should comply with these requirements. On the backside should be allowed discoloration and knots up to 30 mm.

Aspen

One side is knotless. There should not be allowed any coloured stains, discoloration, knots, wane edge, mechanical defects, fault core, heartwood, log blue, or touchwood. One-half of the board thickness should comply with these requirements. On the backside should be allowed discoloration and knots up to 20 mm.

Pine and spruce

Pine, spruce

ГОСТ 26002-83 Sort 1…4. Wane edge, unsound and punk knots, borer holes, mechanical defects, log blue, touchwood should not be allowed. Black knots not above 10 mm. Sound knots should be allowed in any amount, diameter up to 40 mm. The boards should be well sawn and hard-sized. The sawn wood should have its ends trimmed. One package should contain the boards of one size and one length only.

ГОСТ 26002-83 :: Nordic Timber
Sort 1…2:: Sort А
Sort 1…3 :: Sort АВ
Sort 1…4 :: Sort В
Sort 5 :: Sort С

Pine, spruce

SAWN WOOD QUALITY CLASSIFICATION

A – four-edged material with sound knots, single black knots below 8 mm should be allowed. It complies with the Scandinavian Standard U/S (unsorted), mainly sorted pine.

B – four-edged material with sound knots, scanty black knots above 8 mm should be allowed. It complies with the Scandinavian Standard V, mainly sorted pine.

AB – four-edged material with sound knots, scanty black knots above 8 mm should be allowed, with quality A unsorted. It complies with the Scandinavian Standard SF (U/S+V), mainly sorted spruce.

ABC – four-edged material, black knots should be allowed, with quality A and B unsorted. It complies with the Scandinavian Standard SF +VI (U/S+V+VI).

C – four-edged material. It complies with the Scandinavian Standard VI, spruce and pine sorting.

Pine, spruce

Quality
Sound knots but "thumb nail" knots accepted, must be square edged, no bad shake, ends trimmed, no sign of insect attack, well sawn down the length, full to measure.SF+10%(6)