Information and Timber Glossary

Timber conversions

1” = 4/4” = INCH= 25,4 mm
1’= FOOT=304,8 mm
1,5”=6/4=38,1 mm
2”=8/4=50,8 mm
2,5”=10/4=63,5 mm
3”=12/4=76,2 mm
4”=16/4=101,6 mm
1m=3,281 feet
1m³= 424 board feet (BF)
1,000BF=1MBF=2,36 m³


The actual board feet of kiln dried lumber measured after kiln drying


The actual board feet measured before kiln drying.
When sold on this basis, the buyer can expect to receive 7% less board feet because of shrinkage in the kiln drying process.


Inner core of the tree trunk comprising the annual rings containing non living elements. In some species heartwood has a prominent color different from sapwood.


Outer layer of growth between the bark and the heartwood which contain the sap.

Main methods of timber shawing


The process makes a series of parallel cuts through the length of the log resulting in parallel slices or slabs having the growth rings parallel to the board’s wide face and less than 30 degrees orientation to the surface of the board.


Quarter sawn lumber is produced by first quartering the log and then sawing it perpendicular to the growth rings. Boards sawn are of radial grain. Essentially quarter sawing tries to make the annual rings as short as possible at 90 degrees (60 to 90 degrees angle) to the cut surface.


Rift sawing is very similar to quarter sawing. This method accentuates the vertical grain and minimizes the flake, common in quarter-sawn oak. The angle of the cut is 30 degree or greater. Rift sawn is the cut, which falls between crown and true quarter sawn. It is straight grained and in oak, does not reveal any ‘silver ribbon’ grain features.

Hardwood grading rules


The FAS grade, “FIRST AND SECONDS”, will provide the user with long, clear cuttings. The FAS grade includes a range of boards that yield from 83% to 100% clear-wood cuttings over the entire surface of the board. Both faces of the board must meet the requirement for FAS.


This grade is nearly always shipped with FAS. The better face must meet all FAS requirements while the poor face must meet all the requirements of the number 1 Common grade, thus ensuring buyer with at least one FAS face.


The Selects grade is virtually the same as F1F except for the minimum board size required. This grade is generally associated with the northern regions of the USA and is also shipped in combination with the FAS grade. Whether FAS is combined with F1F (Face and better) or Selects (Sel And Better) every board in the shipment must have a minimum of one FAS face.


This grade has evolved for the export market. It is square edged and virtually wane free. The minimum clear yield will be select and better with appearance being a major factor.


For export market market the clear yield should be number 1 Common or slightly better with appearance a main factor. (Number. 1 Common)
Both faces of the board must meet the minimum requirement for Number 1 Common. Includes boards that are minimum of 3” wide and 4’ long and will yield clear face cuttings from 66 2/3% up to.

Softwood grading rules

SAPS: Excellent quality for remanufacture where clear or painted finishes are required, reasonable clear, but allows small characteristics.

PRIME: Excellent quality for remanufacture where clear or painted finishes are required. One side has knots, red stripe. Generally available in larger sizes than Saps.

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