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55-413: Sill plates are usually composed of lumber but can be any material. The timber at the top of a wall is often called a top plate, pole plate, mudsill, wall plate or simply "the plate". In historic buildings the sills were almost always large, solid timbers framed together at the corners, carry the bents , and are set on the stone or brick foundation walls, piers , or piles (wood posts driven or set into

110-400: A 1-inch-thick (25 mm) board, 8/4 (eight quarter) is a 2-inch-thick (51 mm) board, etc. This "quarter" system is rarely used for softwood lumber; although softwood decking is sometimes sold as 5/4, even though it is actually one inch thick (from milling 1 ⁄ 8  in or 3.2 mm off each side in a motorized planing step of production). The "quarter" system of reference is

165-472: A framer much time, because they are pre-cut by the manufacturer for use in 8-, 9-, and 10-foot ceiling applications, which means the manufacturer has removed a few inches or centimetres of the piece to allow for the sill plate and the double top plate with no additional sizing necessary. In the Americas, two-bys (2×4s, 2×6s, 2×8s, 2×10s, and 2×12s), named for traditional board thickness in inches, along with

220-420: A more complex structure than softwoods and are often much slower growing as a result. The dominant feature separating "hardwoods" from softwoods is the presence of pores, or vessels . The vessels may show considerable variation in size, shape of perforation plates (simple, scalariform, reticulate, foraminate), and structure of cell wall, such as spiral thickenings. As the name suggests, the wood from these trees

275-423: A pit for the pitman who worked below. In 1420 the island of Madeira  – an archipelago comprising four islands off the northwest coast of Africa and an autonomous region of Portugal – was discovered. King Henry VI sent settlers to Madeira and the settlers started clearing the huge expanses of forest in order to grow crops. Felled trees were made into planks by water-powered mills and

330-401: A primary sawmill . Re-sawing is the splitting of 1-to-12-inch (25–305 mm) hardwood or softwood lumber into two or more thinner pieces of full-length boards. For example, splitting a 10-foot-long (3.0 m) 2×4 ( 1 + 1 ⁄ 2 by 3 + 1 ⁄ 2  in or 38 by 89 mm) into two 1×4s ( 3 ⁄ 4 by 3 + 1 ⁄ 2  in or 19 by 89 mm) of the same length

385-462: A relatively small set of specified lengths; in all cases hardwoods are sold to the consumer by the board-foot (144 cubic inches or 2,360 cubic centimetres), whereas that measure is not used for softwoods at the retailer (to the cognizance of the buyer). Also in North America, hardwood lumber is commonly sold in a "quarter" system, when referring to thickness; 4/4 (four quarter) refers to

440-452: A timber is referred to as one "timber" (材), and the dimensions of other structural components were quoted in multiples of "timber"; thus, as the width of the actual timber varied, the dimensions of other components were easily calculated, without resorting to specific figures for each scale. The dimensions of timbers in similar applications show a gradual diminution from the Sui dynasty (580–618) to

495-443: A traditional North American lumber industry nomenclature used specifically to indicate the thickness of rough sawn hardwood lumber. In rough-sawn lumber it immediately clarifies that the lumber is not yet milled, avoiding confusion with milled dimension lumber which is measured as actual thickness after machining. Examples – 3 ⁄ 4 -inch, 19 mm, or 1x. In recent years architects, designers, and builders have begun to use

550-426: A unit of dimensional lumber is limited by the height and girth of the tree it is milled from. In general the maximum length is 24 ft (7.32 m). Engineered wood products, manufactured by binding the strands, particles, fibers, or veneers of wood, together with adhesives, to form composite materials, offer more flexibility and greater structural strength than typical wood building materials. Pre-cut studs save

605-468: Is wood that has been processed into uniform and useful sizes (dimensional lumber), including beams and planks or boards . Lumber is mainly used for construction framing , as well as finishing (floors, wall panels , window frames ). Lumber has many uses beyond home building. Lumber is referred to as timber in the United Kingdom, Europe, Australia, and New Zealand, while in other parts of

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660-410: Is a code beaten on to cut wood by a specially made hammer to show the logging licence. The basic understanding of lumber, or "sawn planks", came about in North America in the seventeenth century. Lumber is the most common and widely used method of sawing logs. Plain sawn lumber is produced by making the first cut on a tangent to the circumference of the log. Each additional cut is then made parallel to

715-514: Is considered re-sawing. Structural lumber may also be produced from recycled plastic and new plastic stock. Its introduction has been strongly opposed by the forestry industry. Blending fiberglass in plastic lumber enhances its strength, durability, and fire resistance. Plastic fiberglass structural lumber can have a "class 1 flame spread rating of 25 or less, when tested in accordance with ASTM standard E 84," which means it burns more slowly than almost all treated wood lumber. A timber mark

770-543: Is critical, such as trusses , rafters , laminating stock, I-beams and web joints. Machine grading measures a characteristic such as stiffness or density that correlates with the structural properties of interest, such as bending strength . The result is a more precise understanding of the strength of each piece of lumber than is possible with visually graded lumber, which allows designers to use full-design strength and avoid overbuilding. In Europe, strength grading of rectangular sawn lumber/timber (both softwood and hardwood)

825-633: Is done according to EN-14081 and commonly sorted into classes defined by EN-338. For softwoods, the common classes are (in increasing strength) C16, C18, C24, and C30. There are also classes specifically for hardwoods and those in most common use (in increasing strength) are D24, D30, D40, D50, D60, and D70. For these classes, the number refers to the required 5th percentile bending strength in newtons per square millimetre. There are other strength classes, including T-classes based on tension intended for use in glulam . Grading rules for African and South American sawn lumber have been developed by ATIBT according to

880-450: Is due to the variety of characteristics apparent in different timbers, including density, grain, pore size, growth and fibre pattern, flexibility and ability to be steam bent. For example, the interlocked grain of elm wood ( Ulmus spp.) makes it suitable for the making of chair seats where the driving in of legs and other components can cause splitting in other woods. There is a correlation between density and calories/volume. This makes

935-529: Is from gymnosperm trees). Hardwoods are produced by angiosperm trees that reproduce by flowers, and have broad leaves. Many species are deciduous. Those of temperate regions lose their leaves every autumn as temperatures fall and are dormant in the winter, but those of tropical regions may shed their leaves in response to seasonal or sporadic periods of drought. Hardwood from deciduous species, such as oak, normally shows annual growth rings , but these may be absent in some tropical hardwoods . Hardwoods have

990-554: Is generally harder than that of softwoods, but there are significant exceptions. In both groups there is an enormous variation in actual wood hardness, with the range in density in hardwoods completely including that of softwoods; some hardwoods ( e.g. , balsa ) are softer than most softwoods, while yew is an example of a hard softwood. The structural polymers of hardwoods are cellulose , hemicellulose , and lignin . The constituents of hardwood lignin differs from those included in softwood. Sinapyl alcohol and coniferyl alcohol are

1045-406: Is minimally 1 + 1 ⁄ 2 by 3 + 1 ⁄ 2 inches (38 mm × 89 mm). As previously noted, less wood is needed to produce a given finished size than when standards called for the green lumber to be the full nominal dimension. However, even the dimensions for finished lumber of a given nominal size have changed over time. In 1910, a typical finished 1-inch (25 mm) board

1100-515: Is more economical. There are various types of sawing: Dimensional lumber is lumber that is cut to standardized width and depth, often specified in millimetres or inches (but see below for information on nominal dimensions vs. actual dimensions). Carpenters extensively use dimensional lumber in framing wooden buildings. Common sizes include 2×4 (pictured) (also two-by-four and other variants, such as four-by-two in Australia, New Zealand, and

1155-603: Is required. Under the prescription of the Method of Construction (營造法式) issued by the Song dynasty government in the early twelfth century, timbers were standardized to eight cross-sectional dimensions. Regardless of the actual dimensions of the timber, the ratio between width and height was maintained at 1:1.5. Units are in Song dynasty inches (31.2 mm). Timber smaller than the 8th class were called "unclassed" (等外). The width of

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1210-453: Is rich in phenolic compounds, such as stilbenes , lignans , norlignans, tannins , flavonoids . Hardwoods are employed in a large range of applications, including fuel , tools , construction , boat building , furniture making, musical instruments , flooring , cooking , barrels , and manufacture of charcoal . Solid hardwood joinery tends to be expensive compared to softwood. In the past, tropical hardwoods were easily available, but

1265-459: Is smaller than the nominal dimensions because modern technology makes it possible to use the logs more efficiently. For example, a "2×4" board historically started out as a green, rough board actually 2 by 4 inches (51 mm × 102 mm). After drying and planing, it would be smaller by a nonstandard amount. Today, a "2×4" board starts out as something smaller than 2 inches by 4 inches and not specified by standards, and after drying and planing

1320-673: Is supplied in standard sizes, mostly for the construction industry – primarily softwood , from coniferous species, including pine , fir and spruce (collectively spruce-pine-fir ), cedar , and hemlock , but also some hardwood, for high-grade flooring. It is more commonly made from softwood than hardwoods, and 80% of lumber comes from softwood. In the United States and Canada, milled boards are called lumber , while timber describes standing or felled trees. In contrast, in Britain, and some other Commonwealth nations and Ireland,

1375-605: Is well utilised in the construction industry. Attempts to maintain lumber quality over time have been challenged by historical changes in the timber resources of the United States – from the slow-growing virgin forests common over a century ago to the fast-growing plantations now common in today's commercial forests. Resulting declines in lumber quality have been of concern to both the lumber industry and consumers and have caused increased use of alternative construction products. Machine stress-rated and machine-evaluated lumber are readily available for end-uses where high strength

1430-517: The American Lumber Standard Committee , appointed by the U.S. Secretary of Commerce . Design values for most species and grades of visually graded structural products are determined in accordance with ASTM standards, which consider the effect of strength reducing characteristics, load duration, safety, and other influencing factors. The applicable standards are based on results of tests conducted in cooperation with

1485-558: The USDA Forest Products Laboratory. Design Values for Wood Construction, which is a supplement to the ANSI/AF&;PA National Design Specification® for Wood Construction, provides these lumber design values, which are recognized by the model building codes. Canada has grading rules that maintain a standard among mills manufacturing similar woods to assure customers of uniform quality. Grades standardize

1540-404: The "quarter" system in specifications as a vogue of insider knowledge, though the materials being specified are finished lumber, thus conflating the separate systems and causing confusion. Hardwoods cut for furniture are cut in the fall and winter, after the sap has stopped running in the trees. If hardwoods are cut in the spring or summer the sap ruins the natural color of the lumber and decreases

1595-409: The 4×4 (89 mm × 89 mm), are common lumber sizes used in modern construction. They are the basic building blocks 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. Lumber's nominal dimensions are larger than

1650-582: The British Empire. The timber supply began to dwindle at the start of the twentieth century due to significant harvest volumes, so the logging industry was forced to seek timber elsewhere; hence, the expansion into the American West. Logs are converted into lumber by being sawn, hewn , or split . Sawing with a rip saw is the most common method, because sawing allows logs of lower quality, with irregular grain and large knots, to be used and

1705-828: The UK), 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, and twelve feet in length. In Canada and the United States, the standard lengths of lumber are 6, 8, 10, 12, 14, 16, 18, 20, 22 and 24 feet (1.8, 2.4, 3.0, 3.7, 4.3, 4.9, 5.5, 6.1, 6.7 and 7.3 m). For wall framing, precut "stud" lengths are available, and are commonly used. For ceilings heights of 8, 9 or 10 feet (2.4, 2.7 or 3.0 m), studs are available in 92 + 5 ⁄ 8 inches (2.35 m), 104 + 5 ⁄ 8 inches (2.66 m), and 116 + 5 ⁄ 8 inches (2.96 m). The length of

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1760-509: The United States began with the publication of the American Lumber Standard in 1924, which set specifications for lumber dimensions, grade, and moisture content; it also developed inspection and accreditation programs. These standards have changed over the years to meet the changing needs of manufacturers and distributors, with the goal of keeping lumber competitive with other construction products. Current standards are set by

1815-422: The actual standard dimensions of finished lumber. Historically, the nominal dimensions were the size of the green (not dried), rough (unfinished) boards that eventually became smaller finished lumber through drying and planing (to smooth the wood). Today, the standards specify the final finished dimensions and the mill cuts the logs to whatever size it needs to achieve those final dimensions. Typically, that rough cut

1870-520: The amount of oxygen is inadequate. Fungi lumber/timber defects: Following are the insects and molluscs which are usually responsible for the decay of timber/lumber: Hardwood Hardwood is wood from angiosperm trees . These are usually found in broad-leaved temperate and tropical forests . In temperate and boreal latitudes they are mostly deciduous , but in tropics and subtropics mostly evergreen . Hardwood (which comes from angiosperm trees) contrasts with softwood (which

1925-400: The ground). The sill typically carries the wall framing (posts and studs) and floor joists . There are rare examples of historic buildings in the U.S. where the floor joists land on the foundation and a plank sill or timber sill sit on top of the joists. Another rare, historic building technique is for the posts of a timber-frame building to land directly on a foundation or in the ground and

1980-545: The hardwood significantly differs from the softwood, and mainly consists of triterpenoids , polyprenols and other higher terpenes. Triterpenoids commonly purified from hardwoods include cycloartenol , betulin and squalene . Hardwood polyterpenes are rubber , gutta percha , gutta-balatá and betulaprenols. Although in small quantities, hardwoods also contain mono- , sesqui- and diterpenes , such as α- and β-pinenes , 3-carene , β-myrcene , limonene , hinokitiol , δ-cadinene , α- and δ-cadinols , borneol . Hardwood

2035-558: The main monomers of hardwood lignin. Hardwoods contain less amount of non-structural constituents, named extractives , than softwoods. These extractives are usually categorized into three broad groups: aliphatic compounds , terpenes and phenolic compounds . Aliphatic compounds found in hardwoods include fatty acids , fatty alcohols and their esters with glycerol , fatty alcohols (waxes) and sterols (steryl esters), hydrocarbons , such as alkanes , sterols , such as sitosterol , sitostanol and campesterol . The terpene content of

2090-543: The modern era; a 1st class timber during the Sui was reconstructed as 15×10 (Sui dynasty inches, or 29.4 mm). Defects occurring in lumber are grouped into the following four divisions: During the process of converting timber to commercial forms of lumber the following defects may occur: Fungi attack wood (both timber and lumber) when these conditions are all present: Wood with less than 25% moisture (dry weight basis) can remain free of decay for centuries. Similarly, wood submerged in water may not be attacked by fungi if

2145-444: The one before. This method produces the widest possible boards with the least amount of log waste. Lumber manufacturing globally is determined by the preferred style of building; areas with a "wood building culture" (homes were built from wood rather than other materials like brick) are the countries with significant sawmilling industries. Historical wood-frame home building regions are: Europe, North America, Japan. Different areas of

2200-505: The quality of lumber at different levels and are based on moisture content, size, and manufacture at the time of grading, shipping, and unloading by the buyer. The National Lumber Grades Authority (NLGA) is responsible for writing, interpreting and maintaining Canadian lumber grading rules and standards. The Canadian Lumber Standards Accreditation Board (CLSAB) monitors the quality of Canada's lumber grading and identification system. Their common grade abbrievation, CLS, Canadian Lumber Standard

2255-525: The rules of the Sciages Avivés Tropicaux Africains (SATA) and is based on clear cuttings – established by the percentage of the clear surface. In North America, market practices for dimensional lumber made from hardwoods varies significantly from the regularized standardized ' dimension lumber ' sizes used for sales and specification of softwoods – hardwood boards are often sold totally rough cut, or machine planed only on

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2310-417: The sill plate be kept 6 to 8 inches above the finished grade, to hinder termites, and to prevent the sill plate from rotting. In automobiles , the sill plate is located underneath the door and sometimes displays the make or model of the vehicle. In naval architecture , sill also refers to the lower horizontal plate (frame) height, above which doors and access opening are fixed. Lumber Lumber

2365-407: The sills fit between the posts and are called interrupted sills . In modern wood construction, sills usually come in sizes of 2×4, 2×6, 2×8, and 2×10. In stick framing , the sill is made of treated lumber , and is anchored to the foundation wall, often with J-bolts , to keep the building from coming off the foundation during a severe storm or earthquake. Building codes require that the bottom of

2420-550: The supply of some species, such as Burma teak and mahogany , is now becoming scarce due to over-exploitation. Cheaper "hardwood" doors, for instance, now consist of a thin veneer bonded to a core of softwood, plywood or medium-density fibreboard (MDF). Hardwoods may be used in a variety of objects, but are most frequently seen in furniture or musical instruments because of their density which adds to durability, appearance, and performance. Different species of hardwood lend themselves to different end uses or construction processes. This

2475-459: The term timber is used in both senses. (In the UK, the word lumber is rarely used in relation to wood and has several other meanings.) Re-manufactured lumber is the result of secondary or tertiary processing of previously milled lumber. Specifically, it refers to lumber cut for industrial or wood-packaging use. Lumber is cut by ripsaw or resaw to create dimensions that are not usually processed by

2530-480: The timber (cedar and yew) was shipped to Portugal and Spain. About 1427, the first sawmill in Germany was built. Cornelis Corneliszoon (or Krelis Lootjes) was a Dutch windmill owner from Uitgeest who invented the first mechanical sawmill, which was wind-powered, on 15 December 1593. This made the conversion of log timber into planks 30 times faster than previously. The circular saw, as used in modern sawmills,

2585-405: The trunks of trees were split with wedges into as many and as thin pieces as possible. If it was necessary to have them still thinner, they were hewn, by some sharp instrument, on both sides, to the proper size. This simple but wasteful manner of making boards is still continued in some places. Otherwise, logs were sawn using a two-person whipsaw, or pit-saw, using saddleblocks to hold the log, and

2640-453: The two (broader) face sides. When hardwood boards are also supplied with planed faces, it is usually both by random widths of a specified thickness (normally matching milling of softwood dimensional lumber) and somewhat random lengths. But besides those older (traditional and normal) situations, in recent years some product lines have been widened to also market boards in standard stock sizes; these usually retail in big-box stores and using only

2695-459: The value of the wood for furniture. Engineered lumber is lumber created by a manufacturer and designed for a certain structural purpose. The main categories of engineered lumber are: In the United States, pilings are mainly cut from southern yellow pines and Douglas-fir . Treated pilings are available in chromated copper arsenate retentions of 0.60, 0.80 and 2.50 pounds per cubic foot (9.6, 12.8 and 40.0 kg/m ) if treatment

2750-536: The world (mainly the United States and Canada) the term timber refers specifically to unprocessed wood fiber , such as cut logs or standing trees that have yet to be cut. Lumber may be supplied either rough- sawn , or surfaced on one or more of its faces. Rough lumber is the raw material for furniture-making, and manufacture of other items requiring cutting and shaping. It is available in many species, including hardwoods and softwoods , such as white pine and red pine , because of their low cost. Finished lumber

2805-417: The world are recognized as significant timber suppliers; however, these areas (Indonesia, Sarawak, New Guinea, etc.) are exporters of raw logs and do not have a significant domestic lumber producing industry. The largest lumber manufacturing regions in the world are: China (18%); United States (17%); Canada (10%); Russia (9%); Germany (5%); Sweden (4%). In early periods of society, to make wood for building,

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2860-525: Was 13 ⁄ 16  in (21 mm). In 1928, that was reduced by 4%, and yet again by 4% in 1956. In 1961, at a meeting in Scottsdale, Arizona, the Committee on Grade Simplification and Standardization agreed to what is now the current U.S. standard: in part, the dressed size of a 1-inch (nominal) board was fixed at 3 ⁄ 4  inch; while the dressed size of 2 inch (nominal) lumber

2915-516: Was reduced from 1 + 5 ⁄ 8  inch to the current 1 + 1 ⁄ 2  inch. Dimensional lumber is available in green, unfinished state, and for that kind of lumber, the nominal dimensions are the actual dimensions. Individual pieces of lumber exhibit a wide range in quality and appearance with respect to knots, slope of grain, shakes and other natural characteristics. Therefore, they vary considerably in strength, utility, and value. The move to set national standards for lumber in

2970-693: Was built at the Falls of Piscatauqua , on the line between the Province of Maine and the Province of New Hampshire , in 1634. Unauthenticated records, however, claim that as early as 1633 several mills were operating in New Netherland . The American colonies were essential to England in the role of supplier of lumber for the British fleet. By the 1790s, New England was exporting 36 million feet of pine boards and at least 300 ship masts per year to

3025-541: Was invented by an Englishman named Miller in 1777. It was not until the nineteenth century, however, that it was generally applied, and its great work belongs to that period. The first insertable teeth for this saw were invented by W. Kendal, an American, in 1826. Logging in the American colonies began in 1607 when the Jamestown settlers cut timber to build the first settlement in the new world. America's first sawmill

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