Timber

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(Redirected from Lumber)
For the musical term timbre, see timbre.

Template:For Image:Timber DonnellyMills2005 SeanMcClean.jpg Timber is a term used to describe wood, either standing or that has been processed for use—from the time trees are felled, to its end product as a material suitable for industrial use—as structural material for construction or wood pulp for paper production. In the U.K. and Australia, "timber" is a term also used for sawed wood products (that is, boards), whereas in the U.S. and Canada, the product of timber cut into boards is referred to as lumber. Image:Logs at woodmill.jpg Image:Wood from victoria mountain ash.jpg

Lumber is supplied either rough or finished. Rough lumber is the raw material for furniture making and other items requiring additional cutting and shaping. It is available in many species, usually hardwoods. Finished lumber is supplied in standard sizes, mostly for the construction industry, and is primarily one of a few coniferous needle-bearing species such as pine, hemlock, fir or spruce.

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History and geography

Lumber was one of the first industries in the United States. Maine was an early leading producer, however, later expansion led to Oregon, Washington, and California assuming the lead in domestic lumber production. Logging, the felling and preparation of trees for lumber was a related frontier industry; various tales of lumberjacks were a substantial portion of a certain chapter in North American folklore.

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Classifications

Rough lumber comes from the sawmill without further cutting or shaping. It is usually sold in random lengths and widths and measured in the USA and Canada in board feet, a unit of 1 foot × 1 inch × 1 foot. It is available air-dried or kiln-dried. Air-dried lumber is carefully stacked and allowed to dry for several months, depending on thickness. It is used for some outdoor purposes, such as building sheds and fences. Kiln-dried wood is stacked and dried in moisture- and temperature-controlled kilns built for the purpose. It is then ready to be used for furniture-making or other woodworking uses.

Finished lumber is usually kiln-dried then planed and cut to predetermined sizes, primarily for use by the construction industry. When using Imperial or U.S. customary measurements, the widths given are from before planing, whereas the piece actually sold is smaller; a 2×4 for example is actually only 1½ by 3½ inches after planing. Other stock is sized similarly. The lengths are actual sizes and are multiples of 2 feet. Sizes from 8 to 16 feet (8, 10, 12, 14, 16) are commonly available, and larger sizes (18, 20, 22, 24) are sometimes available. When using metric measurements, lumber is measured in actual sizes.

In the United States, timber is cut in the forest in 24 foot lengths. At the mill it is recut into 3–8 foot lengths, an 8 foot and a 16 foot length, a 10 foot and a 14 foot length or two 12 foot lengths.

Lumber is also used to refer to plywood and other composite wood products. Template:-

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Dimensional lumber

Dimensional lumber is a term used in North America for lumber that is cut to standardized width and depth specified in inches. Template:-

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Softwoods

Softwood Dimensional Lumber Sizes
Nominal Actual Nominal Actual
1 × 2 ¾″ × 1½″ (19×38 mm) 2 × 2 1½″ × 1½″ (38×38 mm)
1 × 3 ¾″ × 2½″ (19×64 mm) 2 × 3 1½″ × 2½″ (38×64 mm)
1 × 4 ¾″ × 3½″ (19×89 mm) 2 × 4 1½″ × 3½″ (38×89 mm)
1 × 6 ¾″ × 5½″ (19×140 mm) 2 × 6 1½″ × 5½″ (38×140 mm)
1 × 8 ¾″ × 7¼″ (19×184 mm) 2 × 8 1½″ × 7¼″ (38×184 mm)
1 × 10 ¾″ × 9¼″ (19×235 mm) 2 × 10 1½″ × 9¼″ (38×235 mm)
1 × 12 ¾″ × 11¼″ (19×286 mm) 2 × 12 1½″ × 11¼″ (38×286 mm)
3 × 4 2½″ × 3½″ (64×89 mm) 2 × 14 1½″ × 13¼″ (38×337 mm)
4 × 4 3½″ × 3½″ (89×89 mm) 6 × 6 5½″ × 5½″ (140×140 mm)
4 × 6 3½″ × 5½″ (89×140 mm) 8 × 8 7¼″ × 7¼″ (184×184 mm)

Examples of common sizes are 2×4 (also two-by-four and other variants), 2×6, and 4×4. The length of a board is usually specified separately from the width and depth. It is thus possible to find 2×4s that are four, eight, or twelve feet in length. In the United States the standard lengths of lumber are 8, 10, 12, 14, 16, 18, 20, 22, and 24 feet.

In The Americas, two-bys (2×4s, 2×6s, 2×8s, 2x10s, and 2×12s) are common lumber sizes used in modern construction. They are the basic building block for such common structures as balloon-frame or platform-frame housing. Dimensional lumber made from softwood is typically used for construction, while hardwood boards are more commonly used for making cabinets or furniture.

The nominal size of a board varies from the actual size of the board. This is due to planing and shrinkage as the board is dried. This results in the final lumber being slightly smaller than the nominal size. Also, if the wood is surfaced when it is green, the initial dimensions are slightly larger (e.g. 1/16″ bigger for up to 4″ nominal lumber, 1/8″ for 5″ and 6″ nominal lumber, 1/4″ bigger for larger sizes). As the wood dries, it shrinks and reaches the specified actual dimensions. Template:-

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Non-North American sizes

Examples of Dimensional Lumber Sizes (Softwood and Hardwood)
Inch name Sawed Swedish Australian
2 × 4 50 x 100 mm 45 × 95 mm 45 x 90mm
1 × 3 25 × 75 mm 22 × 70 mm 19 x 70mm
3 × 3 75 × 75 mm 70 × 70 mm 70 x 70 mm
2 × 7 50 × 175 mm 45 × 170 mm Not used
2 × 3 50 × 75 mm 45 × 70 mm 45 x 70 mm
1 × 4 25 × 100 mm 22 × 95 mm 19 x 90 mm
1 × 5 25 × 125 mm 22 × 120 mm 19 x 120 mm
2 × 5 50 × 125 mm 45 × 120 mm 45 x 120 mm

Outside North America sizes of timber vary slightly. Sizes are, in some cases, based on the imperial measurement and referred to as such; in other cases the sizes are too far removed from the imperial size to be referred to by imperial measurement. Lengths are sold every 300 mm (a metric approximation of 1'). Common sizes are similar to the North American equivalent; 2.4, 2.7, 3.0, 3.6, 4.2, 4.8, 5.4, 6.0.

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Hardwoods

Hardwood Dimensional Lumber Sizes
NominalSurfaced 1 Side (S1S)Surfaced 2 sides (S2S)
3/8″ 1/4″ 3/16″
1/2″ 3/8″ 5/16″
5/8″ 1/2″ 7/16″
3/4″ 5/8″ 9/16″
1″ or 4/4 7/8″ 13/16″
1-1/4″ or 5/4 1-1/8″ 1-1/16″
1-1/2″ or 6/4 1-3/8″ 1-5/16″
2″ or 8/4 1-13/16″ 1-3/4″
3″ or 12/4 2-13/16″ 2-3/4″
4″ or 16/4 3-13/16″ 3-3/4″

In North America sizes for dimensional lumber made from hardwoods varies from the sizes for softwoods. Boards are usually supplied in random widths and lengths of a specified thickness, and sold by the board-foot (144 cubic inches). This does not apply in all countries, for example in Australia many boards are sold to timber yards in packs with a common profile (dimensions) but not necessarily of consisting of the same length boards.

Also in North America hardwood lumber is commonly sold in a “quarter” system when referring to thickness. 4/4 (four quarters) refers to a one-inch thick board, 8/4 (eight quarters) is a two-inch thick board, etc. This system is not usually used for softwood lumber, although softwood decking is sometimes sold as 5/4 (actually one inch thick).

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Trivia

Due to its positive connotations to blue-collar work, the 2×4 has been adopted by World Wrestling Entertainment entertainer “Hacksaw” Jim Duggan.

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Preservatives

Template:Main Timber or lumber may be treated with a preservative that protects it from being destroyed by insects, fungus or exposure to moisture. Generally this is applied through combined vacuum and pressure treatment. The preservatives used to pressure-treat lumber are classified as pesticides. Treating lumber provides long-term resistance to organisms that cause deterioration. If it is applied correctly, it extends the productive life of lumber by five to ten times. If left untreated, wood that is exposed to moisture or soil for sustained periods of time will become weakened by various types of fungi, bacteria or insects.

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Timber framing

Timber framing is a style of construction which uses heavier framing elements than modern stick framing, which uses dimensional lumber. The timbers originally were tree boles squared with a broadaxe or adze and joined together with joinery without nails. A modern imitation with sawn timbers is growing in popularity in the USA.

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Miscellaneous

The term TIMBER! is used as a warning call to alert others working in the area that a tree is being felled and that they should take care to be out of the way. People may also use the term in this way to refer to other objects that are about to fall.

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See also

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External links

de:Timber it:Legname no:Tømmer sv:Timmer

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