Continuing Education in Commercial Lumber

Commercial lumber is basically any lumber traded inFinished hardwood market products are graded in
the free market system, bought or sold at either thefinished form and generally require no further
retail or wholesale level. It comes in many forms,processing. Examples of finished products include
types and species, and is generally graded intosiding, stair treads and risers, trim and moulding,
categories of quality to enable users to select theconstruction boards and timbers, and hardwood
quality best suited for their purposes.flooring. Of these hardwood flooring is probably the
The grading of commercial lumber is based upon thehighest volume product on the market.
characteristics and features that may lower itsSoftwood lumber has been used for many years as
strength, durability or appearance. Knots, checks andthe primary raw material for use in construction and
pitch pockets are some of the visual features thatmanufacturing. It is produced in a wide variety of
are a natural part of trees. While those grades thatproducts and from a wide variety of species.
make up the vast majority of commercial lumber canSoftwood lumber can be classified by its species,
contain numerous knots and other features, somegrade and form of manufacture, and can be graded
grades are virtually free of such features.into the three main use categories of yard lumber,
Lumber can be divided into two major categories:structural lumber, and factory and shop lumber.
hardwood and softwood. Hardwood lumber isYard lumber can be further graded into "Select" and
primarily used for remanufacturing into furniture,"Common" classes. Select lumber is usually not graded
flooring, paneling, moulding, cabinetry and otheraccording to strength but rather according to
millwork. Softwood lumber is primarily used forappearance, as it is generally intended to receive
construction work.natural or paint finishes. Common lumber is also not
Hardwood lumber can be graded into the three mainusually graded for stress, is of lower appearance than
categories of factory lumber, dimensioned lumber andthe Select grade, but is suitable for light construction
finished products.and utility uses.
There are several grades of hardwood factoryStructural lumber is almost always produced in
lumber. The best grade is known as "FAS"; thestandard dimensional sizes, graded for stress and
second-best grade is "FIF"; and the third-best gradestrength, and assigned allowable structural properties.
is called "Selects". These grades are followed by "No.As the name implies, structural lumber is used as
1 Common", "No. 2A Common", No. 2B Common",structural members in construction.
"Sound Wormy", "No. 3A Common" and "No. 3BFactory and Shop lumber comes in a wide variety of
Common". Hardwood lumber comes in standardspecies, sizes and grades of softwood and is typically
lengths of one foot increments ranging from fourthe raw material for many different secondary
feet to sixteen feet in length. Standard thicknessesmanufacturing uses where appearance and finishing
are in either 1/8 inch or 1/2 inch increments rangingcharacteristics as well as physical properties are
from 3/16 inch to 3-3/4 thicknesses. Hardwoodimportant, such as trim moulding and cabinet stock.
lumber is manufactured to random widths as theVarious inspection bureaus and grading agencies
grades do not specify standard widths.typically supervise the grading processes at lumber
Dimensioned hardwood lumber, also known asmills, provide re-inspection services and write grading
"hardwood dimension stock" or "dimension parts", isrules for the products and species they represent.
stock that has been processed into specific lengths,Architects, engineers and construction contractors
widths and thicknesses and can be eithershould be well versed in the types, grades, species
semi-machined or completely machined products.and physical properties of commercial lumber. The
These products are usually kiln-dried and graded intostudy of commercial lumber is an excellent topic for
the three main classes of "hardwood dimensionthe continuing education requirements of these
parts", "rough solid kiln-dried squares" and "surfacedprofessionals. More information is available from the
solid kiln-dried squares".U.S. Department of Agriculture's Forest Service.